Dissertations / Theses: 'Drying quality'

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McCurdy, Murray Charles. "Efficient Kiln Drying of Quality Softwood Timber." Thesis, University of Canterbury. Chemical and Process Engineering, 2006. http://hdl.handle.net/10092/1097.

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This thesis is a study of the kiln drying of radiata pine with a primary focus on the change in wood colour that occurs during this process. The energy efficiency of the drying process has also been examined using computer modelling. The aim of this work was to develop guidelines for commercial wood dryers who wish to produce high quality appearance grade timber in a competitive commercial environment. The colour change in radiata pine wood during kiln drying is mainly caused by sap compounds accumulating at the wood surface and reacting to form coloured compounds. The initial research involved drying experiments designed to determine the relationship between this colour change and the kiln schedule and also measure the accumulation of colour forming compounds. The kinetics of the colour change reaction were also measured using two methods, one in-vitro and the other using small samples of wood. From these experiments a colour change equation was developed that predicts the rate of colour formation based on the drying conditions and this was incorporated into a kiln stack model along with an energy efficiency model. The combined model was used to simulate the drying process to find schedules optimised for energy use and wood quality. The model was also used to simulate the energy efficiency of different humidity control configurations for wood drying kilns. A kiln micro-sensor system was also developed for use in kiln diagnostics and control with the particular aim of identifying areas in wood drying kilns with adverse drying conditions. The recommendation to kiln operators wishing to reduce colour change is to not exceed 70? and to use lower relative humidity schedules with a wet bulb depression of 15-20?. Operating at lower humidity can increase the energy used by the kiln so it is also recommended that kiln designers incorporate heat recovery into the humidity control mechanisms of the kiln.

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Shahverdi, Mahdi. "Kiln drying optimization for quality hem-fir lumber." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/56286.

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Western hemlock is a dominant coastal species in British Columbia, Canada. This species is commonly marketed with amabilis fir as Pacific Coast Hemlock or hem-fir. Hem-fir is difficult to dry, mostly because of the existence of wetwood and large initial moisture content variation. The dried lumber will likely end up with a large final moisture content difference resulting in increased drying defects and decreased lumber quality and factory productivity. In this study, application of green chain moisture-based sorting coupled with drying schedule modifications were considered as ways to improve final moisture content variation within and between kiln dried hem-fir lumber. There were two research phases. The first (without sorting), aimed to develop a modified drying schedule whereas in the second, the developed schedule was used along with a standard industrial schedule. Additionally, there was a green moisture content pre-sorting component in the second phase where freshly cut specimens were sorted based on their initial moisture content into three groups, i.e., mixed, low, and high moisture. To assess the specimen kiln dried quality, final moisture content variation, moisture content gradient, drying rate, warp, surface and internal checks, shrinkage, and casehardening were assessed. Data analysis revealed that there was no significant difference between the drying runs in terms of final moisture content variation, except in the high initial moisture content group. High initial moisture content sorting helped to reduce the final moisture content variation. The modified schedule, when there was a high initial moisture content sorting, also improved the uniformity of final moisture content in comparison to the industrial schedule. Moreover, neither the moisture sorting nor the drying schedule did affect the final moisture content variation for the low and mixed initial moisture content groups. Therefore, the green moisture-based pre-sorting was statistically effective just in the sorted group with high initial moisture content and where the modified schedule was used.
Forestry, Faculty of
Graduate

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Deomano, Edgar Dela Cruz. "Mechanism of Flake Drying and Its Correlation to Quality." Diss., Virginia Tech, 2001. http://hdl.handle.net/10919/28452.

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This research focuses on experimental investigations of the drying and bending properties of wood flakes. Three species (southern yellow pine, sweetgum, and yellow-poplar) were tested. Experiments on flake drying and effect of flake properties (cutting direction and dimension) and an external factor (temperature) were used to evaluate the flake drying process. Drying experiments were conducted using a convection oven. Bending properties of dried flakes were also measured. Modulus of elasticity (MOE), modulus of rupture (MOR), and strength at proportional limit (SPL) of flakes were measured based on Methods of Testing Small Clear Specimens of Timber (ASTM D143-94) using a miniature material tester. The drying curve was characterized by a second-order/quadratic equation. This equation was then differentiated to get the drying rate curve. Observation on drying and drying rate curves revealed that the rate of moisture loss consists of two falling rate periods; no constant rate drying period was observed. First falling rate drying period is controlled by convective heat transfer. Bound water diffusion controls the second falling rate drying period. Species, cutting direction, dimension, and temperature were found to have significant effect on drying rate of wood flakes. Southern yellow pine has the fastest drying rate followed by sweetgum then yellow-poplar. Differences in drying rate between species were attributed to differences in specific gravity and other factors. Radially-cut specimens have a slower drying rate than tangentially-cut specimens. There were also significant differences in drying rate between the four different flake dimensions. Thickness was found to be the more sensitive parameter in terms of dimensions. As expected, drying temperature also had highly significant effect on drying rate. An increasing trend in drying rate was observed as drying temperature increased. Simulation of flake drying using a numerical model yielded a different result. Simulated flake drying has two drying periods: a constant rate and falling rate. Moisture of the flake decreases constantly and surface temperature increases rapidly to boiling point and remains there in the constant rate drying period. During the falling rate period, rate of moisture transport is limited by the ability of water to diffuse through wood and flake temperature starts to rise. Bending properties were found to vary between and within the three species. Southern yellow pine had the lowest bending stiffness and strength followed by sweetgum while yellow-poplar had the highest bending properties. Radially-cut specimens were found to have lower MOE, MOR, and SPL than tangentially-cut specimens. Drying temperature was also found to have a significant effect on bending stiffness and strength. A decreasing trend in bending properties was observed when drying temperature was increased.
Ph. D.

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Li, Heping. "Microwave assisted osmotic dehydration of apple cylinders under continuous medium flow conditions for improving moisture transfer rate and product quality." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=85933.

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Microwave assisted osmotic dehydration (MWOD) under continuous medium flow conditions is a new process with good potential for quality optimization. It combines microwave process with osmotic dehydration and improves the mass transfer rate of osmotic dehydration process and product quality. The thesis describes the design and development of this process.
Preliminary studies on osmotic dehydration were carried out in two parts. First, the effects of processing time, temperature and solution concentration on mass transfer under conventional osmotic dehydration process were investigated and suitable ranges of parameters: 40-60°C, 40-60°Brix and 3h, for further osmotic dehydration kinetics study were identified. Then, the osmotic dehydration efficiency under continuous flow condition process was evaluated. For this, a continuous flow osmotic contactor was developed and found to be an efficient process in terms of osmotic dehydration of apple cylinders. Solids diffusivity (Ds) was lower in continuous flow osmotic dehydration process compared with conventional osmotic dehydration correspondents (P<0.05). Being a separate operation unit, the dehydration process and solution management can be done in a more efficient way in this process.
Following the preliminary studies, the osmotic contactor was relocated under a microwave oven so that heating and mass transfer operations could be facilitated by continuous microwave treatment providing a microwave assisted osmotic dehydration (MWOD) process. Compared with conventional osmotic dehydration (COD), moisture loss (ML%), solids gain (SG%) and mass transport coefficients (km and ks) of MWOD were improved, the average k m was increased 80% and the average ks was decreased 20%, respectively. Moreover, product rehydration property and color profile were improved. Microwave heating had an important effect on water transfer during the osmotic dehydration. Application of microwave heating to osmotic dehydration process facilitated in increasing moisture loss from the sample and simultaneously restricted the product's solute gain. Higher moisture loss in mass transfers area helped to control and strongly counters the solids gain.
Modeling of the mass transfer phenomenon is necessary to optimize osmotic dehydration processes to have a high product quality at minimum energy costs. To explain the simultaneous mass-flow in an osmo-dehydration process, evaluation of equilibrium kinetics is important. Pseudo-equilibrium (practical equilibrium) and dynamic period data are necessary for estimating the time of osmotic process, and ultimate mass transport of the solutes and water, and hence these data were gathered.
The effect of osmotic dehydration treatment on sample subsequent air drying behavior and product quality parameters were investigated. Compared with control samples, osmostically treated samples moisture diffusivity during subsequent air drying process was reduced over same moisture content range: from 1.18*10-9m2/s to 0.77*10-9--1.07*10 -9 m2/s. Drying rates of MWOD pretreated samples varied depending on treatment conditions. MWOD pretreatment shifted product's color profile to those that can be achieved under freeze drying conditions.
Sorption isotherms induced by osmotic dehydration were studied, using a gravimetric-static method, and fitted to GAB model. Adsorption isotherms of products were affected by drying method and osmotic dehydration pretreatment conditions. Adsorption isotherms of osmo-air dried apple cylinders followed type II isotherms (Sigma shaped curve). Monolayer (Mm) values of the osmo-air dried products were reduced. Sorption isotherms of osmotically treated-air dried products were shifted from the control isotherms.
Overall, this work has demonstrated potential of microwave heating for improving moisture transfer during osmotic dehydration and microwave osmotic treatment on subsequent air drying and resulting product quality, as well as the importance of equilibrium kinetics study in process modeling.

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Fragoso, Flores Maria del Rocio. "NEW AND ENERGY EFFICIENT DRYING FOR PROTEIN MIXTURES : Treatments and drying conditions effects on product quality and kinetics." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for energi- og prosessteknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-24828.

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Drying is an essential process applied in most industry to remove moisture and extend the shelf life of final dried products without refrigeration. The challenges are to develop technologies to minimize the impact to environment and diminishes the losses. In this project some tests will be carried out with protein mixtures using heat pump drying technology and quality properties will be analyzed.

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Gan, Shu Hui. "Improving drying characteristics and quality attributes of edible bird's nest (EBN) processed under intermittent IR-UVC assisted drying." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/41680/.

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The quality of Malaysian edible bird’s nest (EBN) is still regarded inferior due to issues related to nitrite content. In August 2011, the Chinese government imposed a ban on EBN products imported from Malaysia, due to the high level of detectable nitrite (NO2-). This nitrite contamination issue has made a great impact to the edible bird’s industry whereby many EBN farmers, traders and exporters are severely affected. In 2012, the China-Malaysia negotiations agreed on the use of radio frequency identification (RFID) tags on every individual package of Malaysian EBN and set the allowable nitrite limit to be less than 30 ppm, in order to allow exportation of Malaysian EBN to China. The processing methods in EBN industry still remain crude and lack of any form of technology advancement. The purpose of this study was to investigate infrared (IR) coupled with ultraviolet C (UVC) assisted intermittent drying as a mean of EBN processing in order to preserve its nutraceutical properties, ensure nitrite content less than 30 ppm and enhance the commercial value of the dried EBN products. In the present study, EBN were dried by IR assisted drying at low temperature (25°C, 26.7% RH and intermittency =1.00), UVC assisted drying at low temperature (25°C, 26.7% RH and intermittency=1.00) and IR-UVC assisted drying (25°C-40°C, 16.5%-26.7% RH and intermittency=0.20-1.00), respectively. Both engineering properties (drying kinetics, effective moisture diffusivity and effective thermal diffusivity) and quality properties (colour, nitrite content, moisture reabsorption ability, shrinkage, sialic acid retention, antioxidant retention and storage stability) of all dried products were assessed and evaluated. The comparisons were made against samples from fan assisted drying and hot air drying. The results revealed that intermittent infrared (IR) coupled with ultraviolet C (UVC) assisted drying at temperature of 40°C (IR-UVC40) with intermittency.

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Blake, Evelyn Christina. "The effect of drying on the protein nutritional quality of fish." Thesis, University of Nottingham, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328807.

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Rohrbach, Katrin. "Schedule and post-drying storage effects on Western Hemlock squares quality." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/2330.

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This study intends to explore the effects of two drying schedules with options of conditioning and post-drying storage on the drying speed and quality of western hemlock timbers. Western hemlock (Tsuga heterophylla), the species of interest in this study, is one of British Columbia's most abundant tree species that accounts for 75 to 80% of British Columbia's exports to Japan. It is usually combined with amabilis fir (Abies amabilis) for processing and economical purposes. Hemlock is difficult to dry due to its compression wood, wetpockets and large spread of initial moisture content and basic density. Consequently, it seems practical to dry hemlock by itself. In this study, hemlock was dried using two different schedules with optional conditioning and optional seven day post-drying storage in a covered and climatized space. These eight experimental runs were compared to a control run, which utilized an established drying schedule. To assess the kiln dried timber quality, twist, diamonding, and checks were evaluated using pre-drying and post-drying and/or post-storage measurements. Drying times and casehardening were also considered. Data analysis and evaluation illustrated that conditioning and the harsher schedule reduced casehardening, while the milder schedule developed less twist and diamonding. Even though it appears that the control run developed less shape distortions than the treatment runs, the control run required longer drying times. When using the harsher schedule the kiln was immediately available for the next run, and the dried timber could be stored in a covered area in order to level out the moisture gradients and alleviate casehardening. As a subsequent step, the timber could be planed to reduce twist, diamonding and superficial checks.

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Stoll, Manfred. "Effects of partial rootzone drying on grapevine physiology and fruit quality." Title page, contents and summary only, 2000. http://hdl.handle.net/2440/37734.

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Growth, productivity and fruit quality of grapevines are closely linked to soil water availability. Withholding of water for any length of time results in slowed growth. If drought continues yield may be lost. Vines can be manipulated to stimulate early defence mechanisms by decreasing soil water availability. By using an irrigation technique, which allows for separate zones with different soil moisture status, it is possible to stimulate response mechanisms of the root system which are normally related to water stress. The difficulty of separating 'wet' and 'dry' zones was initially overcome by using split-root plants with root systems divided between two containers. Such experiments on split-root model plants resulted in the development of an irrigation technique termed partial rootzone drying (PRD). Results from irrigation experiments using PRD have shown that changes in stomatal conductance and shoot growth are some of the major components affected (Dry et al., 1996). The idea of using irrigation as a tool to manipulate stress responses in this way had its origin in the concept that root- derived abscisic acid (ABA) was important in determining stomatal conductance (Loveys, 1984). Later experiments on split-root plants have demonstrated that many effects of water stress can be explained in terms of transport of chemical signals from roots to shoots without changes in plant water status (Gowing et al., 1990). The necessary chemical signals are provided by the dry roots, and the wet roots prevent the development of deleterious water deficits. The general hypothesis tested during this study was that partial drying of the root system gives rise to a change in the supply of root-derived chemical signals which determine changes in grapevine physiology, thereby affecting fruit quality. Experiments were conducted on split-root vines (Vitis vinifera L. cvs. Cabernet Sauvignon and Chardonnay) grown in pots of different sizes, on field-grown vines which had either their root system divided by a plastic membrane (Vitis vinifera L. cv. Cabernet Sauvignon on own roots or grafted on Ramsey rootstocks) or conventional vines with a non-divided root system (Vitis vinifera L. cv. Cabernet Sauvignon, Shiraz and Riesling) with a commercial PRD irrigation design. The irrigation treatments were vines receiving water on both sides (control) and PRD-treated vines, which only received water on one side at any time. The frequency of alternation of 'wet' and 'dry' sides was determined according to soil moisture and other influences such as rainfall and temperature. In most of the experiments the irrigation was alternated from one side to the other every 10 to 15 days. Chemical signals from roots: the role of ABA and cytokinins Studies on chemical signals have concentrated on ABA and cytokinins (CK). An improved stable isotope dilution protocol, which enables analysis of ABA and CK from the same tissue sample, was developed. Analysis of cytokinins focused on zeatin (Z), zeatin riboside (ZR), zeatin glucoside (ZG) and iso pentenyl adenine (iP). Roots are relatively inaccessible, particularly in field situations. To enable easier access to roots of field-grown vines, split-root vines were planted in a trench which was refilled with a sandy soil. This created a homogenous soil substrate and did not restrict root growth while still allowing access to roots under field conditions. Analyses of root samples of field-grown vines have shown that cytokinins and ABA may originate in roots and their concentrations can be substantially altered during an irrigation cycle. Alternating soil water conditions showed that [ABA] in roots on the 'dry' side was significantly higher compared with the 'wet' side. Due to a reduction in CK on the 'dry' side of PRD-treated vines, the ratio between ABA and CK was substantially changed during an irrigation cycle. The ABA levels in root tissue and in petiole xylem sap were negatively related to stomatal conductance. This further suggests that ABA, mostly synthesized on the 'dry' side of the root system, might be responsible for a decline in stomatal conductance. Furthermore, a higher pH of petiole xylem sap was observed in PRD-treated vines which may also contribute to the regulation of stomatal conductance. Studies on stomatal patchiness showed that non-uniform stomatal aperture occurred in field-grown vines under natural environmental conditions and was more abundant under PRD conditions. The degree of stomatal opening, determined by using a water infiltration technique, correlated with measurement of stomatal conductance. Exogenous application of a synthetic cytokinin (benzyl adenine) can override the possible ABA-mediated stomatal closure resulting from PRD treatment, providing further evidence for the in vivo role of these growth regulators in the control of stomatal conductance. The effect of benzyl adenine was transient, however, requiring repeated applications to sustain the reversal. In addition, CKs may also be important in influencing grapevine growth. Following several weeks of repeated spray applications with benzyl adenine, it was found that the development of lateral shoots in PRD-treated vines was enhanced compared to PRD-treated vines sprayed with water only. This supports the idea that the reduction in lateral shoot development seen in PRD-treated vines is due to a reduced production of CKs (Dry et al., 2000a). By measuring shoot growth rate it was found that one common feature of PRD-treated vines, which were not sprayed with CK, was a reduction of lateral shoot growth. It can therefore be speculated that the reduction in lateral growth is related to a reduced delivery of cytokinins from the roots. Zeatin and zeatin riboside concentration in shoot tips and prompt buds/young lateral shoots were reduced by the PRD treatment providing further evidence in support of this hypothesis. Water movement from 'wet' to 'dry' roots Roots, being a primary sensor of soil drying, play an important role in long- and short-term responses to PRD. Using stable isotopes of water and heat-pulse sap flow sensors water movement was traced from wet to dry roots in response to PRD. The redistribution of water from roots grown in a soil of high water potential to roots growing in a soil of low water potential may be of significance with regard to the movement of chemical signals and the control of water balance of roots. Measurements of the relative water content (RWC) have shown a slower decline of RWC of the 'dry' roots of PRD vines relative to roots of vines which received no water, despite similar water content in soil surrounding those roots. The redistribution of water may help to sustain the response to PRD for longer periods possibly releasing chemical signals and to support the activity of fine roots in drying soil. Field vines, irrigated with PRD over several growing seasons, altered their root distribution relative to the control vines. PRD caused a greater concentration of fine roots to grow in deeper soil layers and this may contribute to a better water stress avoidance. The effect on root growth may be augmented by the water movement and by the large difference in ABA to cytokinin ratio, which are also known to alter root growth. PRD makes more efficient use of available water In experiments where both control and PRD-treated vines received the same amount of water many differences between the vines were demonstrated. Under conditions where water supply was adequate for both treatments, the stomatal conductance and growth of the PRD-treated vines was restricted as has been observed in many previous experiments. As total water input was reduced, however, the stomatal conductance of PRD-treated vines became greater than control vines, suggesting that the latter were experiencing a degree of water stress, whereas the PRD-treated vines were not. This may have been due to the greater depth of water penetration in the case of the PRD-treated vines, where water was applied to a smaller soil surface area. This distinction between PRD-treated and control vines, at very low water application rates, was also reflected in pruning weights and crop yields which were actually greater in PRD-treated vines. It was concluded that at low water application rates, the PRD-treated vines were more tolerant of water stress and made more efficient use of available water. Reduction in vigor opens the canopy. The initial aim of the research which led to the development of PRD was to achieve better control of undesirable, excessive shoot and foliage growth which, from a viticultural point of view, has many disadvantages. Grapevine shoot growth rate responds very sensitively to drying soil conditions. The irrigation strategy used in the PRD experiments maintained a reduction of both main shoot and lateral shoot growth. In response to PRD a decrease in shoot growth rate and leaf area was observed. Much of the reduction in canopy biomass was due to a reduced leaf area associated with lateral shoots, thus influencing the canopy structure. This was one major factor improving the light penetration inside the canopy. Control of vegetative vigour results in a better exposure of the bunch zone to light and, as a consequence, in improved grape quality. It is likely that changes in canopy density, as a result of PRD, is causing changes in fruit quality components. Anthocyanin pigments such as derivatives of delphinidin, cyanidin, petunidin and peonidin were more abundant in berries from PRD vines; by comparison the concentration of the major anthocyanin, malvidin, was reduced. When leaves were deliberately removed from more vigorous control vines, which improved bunch exposure, the differences in fruit composition were much reduced. This further supports the idea that a more open canopy, in response to PRD, improves fruit quality by affecting the canopy structure. Fruit quality consequently determines the quality, style and value of the finished wine. Wines from this study have been produced and data on wine quality from commercial wineries are also available. Sensory evaluations have demonstrated that high wine quality from PRD-treated vineyards can be achieved without any yield-depressing effects. This study has provided evidence to support the original hypothesis. The major findings were: a) Chemical signals, altered under PRD and mostly originating from roots, play an important role in the root to shoot communication in grapevines. b) The movement of water from 'wet' to 'dry' soil layers may help to sustain chemical signals as a response of grapevines to PRD and to support the activity of fine roots in drying soil. c) A reduction in vegetative growth, in particular of lateral shoots, was sustained using PRD and affected the canopy structure which in turn, due to a better light penetration into the canopy, improved the fruit quality. d) The reduction in irrigation water applied did not have a detrimental effect on grape yield and thus the efficiency of water use was improved. e) Application of relatively low irrigation rates showed that PRD-treated vines were more tolerant of water stress and made more efficient use of available water.
Thesis (Ph.D.)--Department of Horticulture, Viticulture and Oenology, 2000.

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Kemzūraitė, Aurelija. "Impact of Drying Environment on Quality Preservation in the Medicinal Raw Material." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20101208_134901-94479.

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The goal of this study is to research and substantiate the impact of drying environment on quality preservation in medicinal raw material, i. e. hyssop herb (Hyssopi herba). A complex impact of the drying environment factors (temperature and comparative ventilation intensity) of medicinal raw material, hyssop herb (Hyssopi herba), on the process of kinetics of its drying within a motionless layer, that was not researched until now, was determined. After the analysis of the medicinal raw material drying regularities the change of moisture in the object being dried was modelled. Both the comparative air flow and the dryer parameters impacted moisture exchange processes, drying time and medicinal raw material quality. Through the application of a complex dryer temperature and comparative airflow combination the environment favourable for medicinal raw material quality preservation is created. A close correlation between the mycobiotic contamination of medicinal raw material and the loss of essential oils was determined upon drying Hyssopi herba within a motionless layer. The theoretical fundamentals for designing medicinal raw material conservation technologies were developed. On the basis of the research findings, a pilot technology for medicinal raw material drying within a bulk motionless layer was developed. The technology was introduced in the medicinal raw material drying room of the Full House Community in village (Varėna district).
Darbo tikslas − ištirti ir pagrįsti vaistinės augalinės žaliavos − isopų žolės (Hyssopi herba) džiovinimo aplinkos įtaką kokybės išsaugojimui. Nustatyta iki šiol nenagrinėta kompleksinė džiovinimo aplinkos veiksnių (temperatūros ir lyginamojo ventiliavimo intensyvumo) įtaka vaistinės augalinės žaliavos − isopų žolės (Hyssopi herba) džiovinimo nejudančiame sluoksnyje proceso kinetikai. Išanalizavus vaistinės augalinės žaliavos džiovinimo dėsningumus, modeliuotas džiovinamo objekto drėgnio kitimas. Lyginamasis oro srautas ir džioviklio parametrai įtakojo drėgmės mainų procesus, džiovinimo trukmę ir vaistinės augalinės žaliavos kokybę. Taikant kompleksinį džioviklio temperatūros ir lyginamojo srauto derinį sukuriama vaistinės augalinės žaliavos kokybei išsaugoti tinkama aplinka. Nustatyta, kad džiovinant Hyssopi herba nejudančiame sluoksnyje yra glaudus ryšys tarp vaistinės augalinės žaliavos mikobiotinio užterštumo ir eterinių aliejų praradimo. Sukurti teoriniai pagrindai vaistinės augalinės žaliavos konservavimo technologijų projektavimui. Remiantis atliktais tyrimų rezultatais patobulinta vaistinės augalinės žaliavos storame nejudančiame sluoksnyje džiovinimo technologija, kuri įdiegta Pilnų namų bendruomenės vaistinės augalinės žaliavos džiovykloje, Varėnos r., Panaros k.

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Forel, Françoise. "Effects on coated paper quality of uncoated and coated sheet drying strategy." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=84246.

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Drying occurs twice during coated paper production: first, when drying the base paper, then when drying the sheet freshly coated with an aqueous suspension of pigment particles. The effects on coated paper quality from the impingement drying conditions used at both base paper and coated paper drying stages were studied for the light weight coated (LWC) paper. A central feature of the study was the development of the capability to dry coated paper by impingement in superheated steam. The variables investigated were the drying fluid, air or superheated steam, drying fluid temperature, drying time and temperature, and coating-to-drying delay time. The effects of drying on the uncoated paper physical properties and the coated paper physical and printing properties were determined.
The drying of the base paper with superheated steam gave higher strength and hydrophobicity but lower optical properties and smoothness than drying in air. When steam-dried base paper was coated and dried in air or steam it gave a rougher, less glossy, less bright coated paper than air-dried base paper. Print mottle remained high when air drying was used subsequently for the coated sheet.
The biggest effect on LWC coated paper quality derived from the choice of drying medium, air or superheated steam. Coating-to-drying delay time had no effect. Most of the properties of steam-dried coated paper were fixed by 0.6 s drying time. Properties the most affected were surface properties: print quality, gloss and roughness, while bulk properties were less sensitive. Drying with superheated steam gave lower gloss and smoothness than drying in air. Print mottle was significantly improved with steam drying of the coated sheet.
Superheated steam drying of coated paper has advantages only if used for the coated sheet not the base sheet.

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Mutukwa, Itai. "Drying and Pretreatments Affect the Nutritional and Sensory Quality of Oyster Mushrooms." Diss., North Dakota State University, 2014. https://hdl.handle.net/10365/27380.

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The effect two drying treatments (solar and oven), three blanching treatments (no blanching, water and steam), and four chemical treatments (no chemical, lemon juice, vinegar and potassium bisulfite) on oyster mushroom quality was investigated. Sensory quality, total phenolics, total flavonoids, ergothioneine, oxygen radical absorbance capacity, moisture, mold infestation, mineral content and protein were evaluated. Among the un-blanched samples, those that were treated with lemon juice and those without any chemical pretreatment before drying had better appearance, flavor and were more generally acceptable than those with vinegar and potassium bisulfite treatments. However, when blanching was done, samples treated with potassium bisulfite had superior sensory quality when compared to lemon juice, vinegar and the control. Solar drying caused more browning when compared to oven drying. The combination of water blanching with either lemon juice or vinegar treatments before drying resulted in higher flavonoid content. Lower ergothioneine and total phenolic compounds were observed in blanched mushrooms compared to the un-blanched ones. Total flavonoids were highest in the water blanched samples and least in the un-blanched ones. Among the chemical pretreatments, higher total phenolic compounds were observed in vinegar and potassium bisulfite treated samples. Blanching resulted in lower K, Mg, Na, S and P content when compared to the control. Mineral nutrients varied with chemical pre-treatments. Blanching followed by either lemon juice or no chemical treatment resulted in high mold infestation. Among the un-blanched samples, those treated with vinegar had the least mold infestation. Drying method, blanching, and chemical pretreatments affected oyster mushroom quality hence a need to carefully select preservation methods so as to minimize quality compromise.

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Cuervo-Andrade, Sandra Patricia [Verfasser]. "Quality oriented drying of Lemon Balm (Melissa officinalis L.) / Sandra Patricia Cuervo-Andrade." Kassel : Universitätsbibliothek Kassel, 2011. http://d-nb.info/101140561X/34.

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Taye, Addisalem Hailu [Verfasser]. "Optimization of drying process for better quality retention of dried potato / Addisalem Hailu Taye." Kassel : Universitätsbibliothek Kassel, 2018. http://d-nb.info/1162154594/34.

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Jovanovic, Stefan. "Quality Characterization and Modeling Experimental Kinetics in Pilot Scale Heat Pump Drying of Green Peas." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for energi- og prosessteknikk, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-21875.

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Drying is one of the most necessary process and technology in today?s world and it is used, among other things, for food processing. The basic goal is to process the food for consumption by increasing its shelf life, and in order to achieve this moisture must be removed from raw material as moisture, which is the main promoter of biological activity and spoilage of the fresh products. Conventional drying is known for its high energy consumption and therefore it is costly. The conventional drying has also a negative impact on the environment and climate, providing the basis for heat pump drying development to ensure sustainable practice within the food industry.Heat pump drying is a relatively new technology developed at NTNU. It unifies the drying and heat pump cycles in which the heat pump is used to recycle energy, for reheat the air during drying the raw material. By recycling the heat from the dryer exhaust, energy is saved and the total energy input to the system is drastically reduced.In this master thesis a laboratory heat pump dryer is applied for drying green peas. The drying air was set on temperature regimes of 45°C, 35°C and 15°C with three levels of relative humidity: 60%, 40% and 20%, from which temperature regime of 45°C was set on 40% and 20%. Therefore, eight drying tests were performed and each test was done in period of three hours. The drying of green peas was conducted in fluidized bed mode.The results have shown that higher temperatures increase the rate of moisture removal from the green peas. Difference in relative humidity of the drying air also plays an important role in the process although the effect is much less compared to the temperature. The tests performed on heat pump drying of green peas provided the experimental data used for modeling and analysis of mass effective diffusivity, moisture content and ratio. The kinetics for all experiments on heat pump drying of green peas were successfully modeled based on the solution of the transient and three-dimensional general equation. Analysis and discussion were also done on the influence that these factors have on color, water activity, bulk and particle density, as well as particle size.Overall the project has shown that heat pump drying has many advantages in producing a satisfactory quality dried green peas, economy and sustainability. Therefore is justifiable to continue further studies and development of heat pump drying technology.

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Bogosavljevic, Dejan. "Effect of fertilization and type of pruning on quality of fresh and dehydrated Stevia rebaudiana." Master's thesis, ISA-UL, 2016. http://hdl.handle.net/10400.5/12206.

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Mestrado em Engenharia Alimentar - Instituto Superior de Agronomia - UL
Stevia rebaudiana is tropical and sub-tropical plant and has been received a large body of attention due to its potential as natural sweetener. In order to contribute to the optimization of the agricultural production in a coastal region in the Lisbon area, with mild climate, an on-farm study was conducted under a context of social agriculture. It was investigated the effects of two levels of pruning and two regimes of fertilization on the plant’s biomass yield and quality, including accumulation of steviol glycosides. The quality differential of leaves was quantified after a customized solar drying coupled with a pre-heat abiotic stress procedure. The results showed that, when growing under just basal fertilization, plants were higher, independently of pruning severity. Additional (foliar) fertilization in light-pruned plants lead to more leaves that in severe-pruned ones and higher leaf areas were observed under severe pruning. Glycosides concentration was not influenced by fertilization, but it was positively influenced by severe pruning resulted in increased amounts, in ca. 29.38% in case of leaves without additional fertilization. In the same time, severe-pruning resulted in higher increase of Stevioside, responsible for bitterer aftertaste, when compared to Rebaudioside A (Rebaudioside A: Stevioside ratio = 0.89). The leaves of Stevia were subjected for 2h to pre-heating and 18h24m of active drying using a SOLAR DRYER until 10.00% of humidity, and with total soluble solids increased ca. 18% and pH decreased ca. 4%. The drying procedure increased Glycosides to 43.06 mg/g dry leaves, from 36.82 mg/g, suggesting secondary metabolites accumulation as a response to abiotic stress. The level of phenolic compounds increased in 100% and antioxidant activity was ca. 3.01 (ABTS) and 4.40 (DPPH) fold higher.

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Al-Bakry, Ahmed Nasser Abdullah. "Regulation of fruit quality in sweet pepper (Capsicum annuum L.) by water stress." Thesis, University of Nottingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368247.

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Du, Yi. "Implementation of a Wetting and Drying Model in Simulating the Androscoggin/Kennebec Plume and the Circulation in Casco Bay." Fogler Library, University of Maine, 2008. http://www.library.umaine.edu/theses/pdf/DuY2008.pdf.

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Santhanam, Menon Abhay. "Effects of blanching and drying on the production of polyphenols rich cocoa beans and product quality." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/43219/.

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The high potential of health beneficial polyphenols and antioxidants in cocoa beans has been a major topic for research in recent years. The large-scale application of cocoa beans for health beneficial compounds is relatively unexplored and it needs to be widely utilized by pharmaceutical and nutraceutical industries. Processing methods such as fermentation and drying are major deterrents for recovering high polyphenols in cocoa beans. Hence, it was the intention of this work to introduce the application of hot water blanching pre-treatment and various drying methods for producing polyphenols rich cocoa beans by using unfermented beans. The studies incorporated the application of various drying methods such as oven, adsorption, vacuum, freeze and sun drying methods on cocoa beans. The studies compared the ability of these drying methods to preserve the bioactive capacities namely, total polyphenolic contents and antioxidants activity after hot water blanching. The potential of adsorption, vacuum and freeze drying methods for recovering high polyphenols content are useful in comparing it with the conventional cocoa drying methods such as oven and sun drying methods. For the studies on oven drying of cocoa beans, the drying parameters (T= 60°C, 70°C and 80°C) used were similar to the conventional hot air drying parameters used in industries. The total polyphenolic contents of fermented cocoa beans dried at 70°C was found to be the highest. The polyphenols degradation kinetics for oven drying method of cocoa beans was determined using first-order reaction kinetics model based on various drying temperatures and durations of drying. The studies on drying kinetics of fresh cocoa beans dried using oven, vacuum, adsorption and sun drying methods were successfully analysed. It was found that adsorption drying and vacuum drying methods dried cocoa beans faster than oven and sun drying methods. Two respective falling rate periods were recorded by adsorption and vacuum drying. The effective diffusivities were determined and were found to be in accordance to that of published literatures. Hot water blanching pre-treatment were performed for fresh and fermented cocoa beans (whole beans and half cut). Blanching pre-treatment method was found to show significantly higher total polyphenolic contents when compared with unblanched cocoa samples. The optimal blanching parameter (90°C for 5 min) obtained for fresh beans were subsequently used for experiments involving fresh cocoa beans. The total polyphenolic contents and antioxidant activity of blanched and unblanched cocoa beans were analysed. Results showed that both adsorption and vacuum drying methods showed high recovery of polyphenolic compounds and antioxidants on comparison with freeze dried cocoa samples, which was used as a benchmark in quality analysis of food products. High polyphenols contents were achieved after the blanching and drying treatments and were noted to be significantly higher on comparison with published literatures. Sensory analysis of both blanched and unblanched cocoa beans were analysed after drying using various drying methods. The results for unfermented cocoa beans showed high astringency flavour attributes which further confirmed the high contents of polyphenols in cocoa beans. The cocoa and acidic flavour attributes were recorded to be less owing to the unfermented nature of cocoa beans. The results obtained provides a gateway towards the use of advanced drying technology in cocoa industry. The potential of blanching pre-treatment to mediate high recovery of cocoa polyphenols after drying has been proven through this work. The processing methods used in the current study can be implemented in on-farm cocoa processing, making it a more sustainable farming option.

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Larrañaga, Michael David. "The capability of a solid sorbent desiccant unit at removing selected indoor air quality-related microorganisms from the air." online access from Digital Dissertation Consortium, 2004. http://libweb.cityu.edu.hk/cgi-bin/er/db/ddcdiss.pl?3215627.

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Salem, Thouraya. "Séchage intermittent du bois d’oeuvre : étude expérimentale et numérique." Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0177/document.

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Le séchage du bois d’œuvre étant une opération très énergivore, l’utilisation des énergies intermittentes est l’une des solutions envisageables afin de réduire la consommation énergétique au cours de cette opération. Néanmoins, ne pouvant utiliser les conduites de séchage actuellement préconisées à cause de la fluctuation de l’apport énergétique, l’utilisation de ce type d’énergies soulève plusieurs questions notamment sur l’impact de la fluctuation de la température sur la qualité du séchage et les conduites de séchage à adopter afin de réaliser un compromis entre durée, qualité et coût. Ce travail de thèse vise à apporter des réponses à ces questions par une approche équilibrée entre expérimentation et modélisation. L’étude expérimentale a montré que l’intermittence des conditions de séchage ne ralentit pas la cinétique de séchage par rapport à un séchage où la teneur en eau d’équilibre et la température moyenne sont identiques et maintenues constantes. De plus, une meilleure qualité semble pouvoir être obtenue par l’intermittence des conditions de séchage. Ces résultats ont été confrontés aux simulations d’un modèle numérique double échelle utilisant le code TransPore à l’échelle de la planche. Son potentiel prédictif a été vérifié et il a ensuite été utilisé pour mieux comprendre l’effet des conditions intermittentes sur la qualité et la durée du séchage à l'échelle d'une planche seule et à l'échelle d'une pile de planches. Il a permis de montrer que l’oscillation des conditions de séchage active la mécanosorption et relaxe une partie des contraintes de séchage. Les gains apportés sont limités à l’échelle d’une planche seule, mais ils peuvent être plus importants à l’échelle d’une pile de planches. Le séchage intermittent s’avère plus intéressant pour un séchage lent tel qu’un séchage à basse température, des essences plus difficiles à sécher ou encore pour des planches de fortes épaisseurs. Le code a été ensuite utilisé pour comparer différentes stratégies de séchage à basse température. Un compromis a pu être obtenu entre durée et qualité en réalisant un pré-séchage avec une énergie intermittente à basse température suivi d’un séchage convectif à plus haute température cependant la durée reste longue pour les autres configurations imposant une étude de faisabilité économique. Un module économique a été développé en Fortran et greffé dans le code numérique multi-échelle Planche-Pile-Séchoir afin d’intégrer le critère coût dans l’étude des différentes stratégies
Timber drying is an energy intensive process, the use of intermittent energy sources is one of the possible solutions to reduce energy consumption during this operation. However, the use of the conventional drying schedules is not suitable because of the fluctuation of energy intake, the use of this type of energy raises several issues as the impact of the fluctuation of temperature on drying quality, or the drying strategies to use in order to achieve a compromise between time, quality and cost. This thesis aims to provide answers to these questions through a balanced approach between experimentation and modeling. The experimental study has shown that intermittent drying conditions do not slow the drying rate compared to drying wherein the equilibrium moisture content and the average dry bulb temperature are identical and maintained constant during drying. Moreover, better quality seems to be obtained by the intermittent drying conditions. These results were compared to simulations of a dual scale numerical model using the code TransPore at the board scale. Its predictive potential was checked and it was later used to better understand the effect of intermittent conditions on the drying quality and time at the board and stack scales. It showed that the oscillation of drying conditions activates the mechanosorption and relaxes some of drying stresses. The benefits on the drying quality are limited when a single board is dried, but benefits may be more important when a boards stack is dried. The intermittent drying seems to be more interesting in the case of slow drying such as drying at low temperature, more difficult species to dry or for thick timbers. The code was then used to compare different drying strategies at low temperature level with oscillate conditions. A compromise was reached between duration and quality by achieving a pre-drying using a low temperature intermittent drying followed by convective drying at higher temperatures, however, the drying time is still long for other configurations imposing an economic feasibility study. An economic module was developed in Fortran and grafted in the multiscale computational model Board-Stack-Kiln to integrate the cost criterion in the study of the different strategies

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McMillan, Jane Elizabeth. "Protein quality and digestibility of whole wheat as affected by drum-drying and single screw extrusion processing." Thesis, Virginia Tech, 1991. http://hdl.handle.net/10919/41693.

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The objective of this study was to examine the effects of two thermal processes, drum-drying and thermoplastic extrusion, on protein quality and digestibility of whole wheat. Coker 916 whole wheat flour was made into a simulated whole wheat spaghetti by extrusion cooking (single screw, 50 psi, 93°C) and a flaked product by drum-drying (152°C). Protein Efficiency Ratios (PER) of the original whole wheat kernels and the two processed wheat products were determined. The apparent digestibility of the four diets was determined from Kjeldahl nitrogen analysis of feces. Amino acid composition, available lysine analysis, colorimetry (Hunter L, a, b color values), and Differential Scanning Calorimetry were also conducted to investigate the effects of thermal processing on protein quality. Both thermal processes significantly increased protein digestibility while PER’s of the drum dried flakes (1.66) and unprocessed whole wheat (1.59) were significantly greater than the extruded product (1.42) Thermal processing also resulted in substantial reductions in lysine (>10%) and several other essential amino acids. Hunter L, a, b values indicated that the drum-dried flakes were lightest in color, followed by the unprocessed whole wheat and the extruded product. The observed decrease in lysine and PER of the extruded product may be due in part to Maillard Browning, as indicated by Hunter color values. It appears that total lysine or Hunter L color values may be reasonable predictors of protein quality of processed whole wheat. DSC results suggest that starch was fully gelatinized during drum-drying of the whole wheat but on partially gelatinized during extrusion cooking.
Master of Science

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Stockinger, Allan Joseph. "Optimizing lanthanum (III) hydroxide by varying drying methods to maximize surface area to adsorb arsenic in water /." abstract and full text PDF (free order & download UNR users only), 2007. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1447803.

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Thesis (M.S.)--University of Nevada, Reno, 2007.
"May 2007." Includes bibliographical references (leaves 72-75). Online version available on the World Wide Web. Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2007]. 1 microfilm reel ; 35 mm.

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Schmitz-Schug, Iris [Verfasser]. "Improving the nutritional quality of dairy powders Analyzing and modeling lysine loss during spray drying as influenced by drying kinetics, thermal stress, physical state and molecular mobility / Iris Schmitz-Schug." München : Verlag Dr. Hut, 2014. http://d-nb.info/1064560059/34.

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Ståhl, Magnus. "Improving Wood Fuel Pellets for Household Use : Perspectives on Quality, Efficiency and Environment." Doctoral thesis, Karlstads universitet, Avdelningen för energi-, miljö- och byggteknik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-2855.

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Bioenergy is one of many contributors to reducing the use of fossil fuels in order to mitigate climate change by decreasing CO2-emissions, and the potential for biofuels are large. The wood fuel pellets are a refined biofuel made of sawdust, which is dried and compressed to achieve improved fuel and transportation properties. In 2007 the amount of wood fuel pellets used for heating purposes in Sweden was 1715000 tons. The aims of this work was: to examine the moisture content and emission of monoterpenes during the drying and pelletising steps of the pellets production (Paper I); to investigate how the recirculation of drying gases affects the energy efficiency of rotary dryers and how the energy efficiency is related to the capacity of the dryer. (Paper II); to analyse the causes of the problems encountered by household end-users of pellets and investigate whether an improved pellet quality standard could reduce these problems (Paper III); to investigate how the energy consumption of the pelletising machine and chosen pellet quality parameters were affected using an increased amount of rapeseed cake in wood fuel pellets (Paper IV); and to identify gaps of knowledge about wood fuel pellet technology and needs for further research on quality, environmental and health aspects throughout the wood fuel pellet chain, from sawdust to heat. (Paper V).

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Masri, Hassan Mohamed. "Evaluating post-harvest practices on the quality and safety of Kona coffee." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/89217.

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Coffee grown in the United States represents less than 1% of the world's supply, and most of it comes from the state of Hawai'i. Kona coffee, grown on the western side of the island of Hawai'i, is the most recognized and the highest value Hawaiian coffee. The majority of this coffee is sun-dried after harvest and washing. Sun-dried coffee should reach 12-13% moisture within 4 to 6 days. Sun-drying will reduce both the moisture content and the water activity (aw). Reducing aw below 0.75, especially in the first week of drying, is important for preventing or limiting mold growth. The purpose of this study was to 1) compare drying rates of Kona coffee bean batches using aw and moisture content % measurements, 2) evaluate factors affecting the drying time of sun-dried Kona coffee, and 3) provide recommendations for post-harvest processing of sun-dried Kona coffee to optimize quality and safety. Ten farms in the Kona coffee region of Hawai'i were visited in the fall of 2017 to record data on the drying rate of coffee bean batches and to record observations on the post-harvest handling and storage of coffee beans and the environmental conditions that may affect the quality and microbial contamination of drying coffee. The coffee drying surfaces, physical enclosures, fan use, and elevation varied among farms. Daily measurements of coffee moisture level, water activity, depth of bean layer and temperature were recorded along with air temperature, relative humidity and cloud cover during drying for 30 batches. Most sun-dried batches reached 13% moisture in 6 to 10 days. Initial moisture content (31.6 4.3%), and drying yard characteristics varied greatly among farms. Coffee batches reached 0.75 aw within 6 days on average, but some batches required more than 10 days. Moisture content and aw measurements were weakly correlated and water activity level increased at times during drying for some batches. Allowing airflow around drying beans and maintaining a bean layer depth of less than 5 cm appeared to improve drying rates. Drying coffee parchments within 7 days post-harvest can inhibit growth of molds that may impact quality or molds that could produce mycotoxin. Controlling the drying conditions, including raking the layered beans, and monitoring moisture content can accelerate, or improve the consistency of, batch drying time.
Doctor of Philosophy
Coffee grown in the United States represents less than 1% of the world’s supply, and most of it comes from the state of Hawai’i. Kona coffee, grown on the western side of the island of Hawai’i, is the most recognized and the highest value Hawaiian coffee. The majority of this coffee is sun-dried after harvest and washing. Sun-dried coffee should reach 12-13% moisture within 4 to 6 days. Sun-drying will reduce both the moisture content and the water activity (aw*). (*Water activity is the measurement of water vapor pressure generated by the free or non-chemically bound water in foods and other products. Water activity (range of 0 to 1) is an important indicator for the shelf life of foods and the occurrence and growth of microorganisms). Reducing aw below 0.75, especially in the first week of drying, is important for preventing or limiting mold growth. The purpose of this study was to 1) compare drying rates of Kona coffee bean batches using aw and moisture content % measurements, 2) evaluate factors affecting the drying time of sun-dried Kona coffee, and 3) provide recommendations for post-harvest processing of sun-dried Kona coffee to optimize quality and safety. Ten farms in the Kona coffee region of Hawai’i were visited in the fall of 2017 to record data on the drying rate of coffee bean batches and to record observations on the post-harvest handling and storage of coffee beans and the environmental conditions that may affect the quality and microbial contamination of drying coffee. The coffee drying surfaces, physical enclosures, fan use, and elevation varied among farms. Daily measurements of coffee moisture level, water activity, depth of bean layer and temperature were recorded along with air temperature, relative humidity and cloud cover during drying for 30 batches. Most sun-dried batches reached 13% moisture in 6 to 10 days. Initial moisture content (27 to 36 %), and drying yard characteristics varied greatly among farms. Coffee batches reached 0.75 aw within 6 days on average, but some batches required more than 10 days. Moisture content and aw measurements were weakly correlated and water activity level increased at times during drying for some batches. Allowing airflow around drying beans and maintaining a bean layer depth of less than 5 cm appeared to improve drying rates. Drying coffee parchments within 7 days post-harvest can inhibit growth of molds that may impact quality or molds that could produce mycotoxin. Controlling the drying conditions, including raking the layered beans, and monitoring moisture content can accelerate, or improve the consistency of, batch drying time.

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Vallespir, Torrens Francisca. "Drying process intensification by using freezing pretreatments and ultrasound application at high and low temperature." Doctoral thesis, Universitat de les Illes Balears, 2019. http://hdl.handle.net/10803/669872.

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[eng] Drying process is commonly used to reduce fruits and vegetables moisture content in order to enlarge their shelf life. However, convective drying can promote product quality parameters losses due to thermal and air exposure. In order to intensify convective drying, both freezing pre-treatment and ultrasound application have been used in this study with the aim of shortening drying time and preserving quality parameters. Consequently, the two general objectives of this work were, on the one hand, to study the drying process intensification at drying temperature above 20 C by using freezing pre-treatments and ultrasound application; and on the other hand, to study also the intensification of the low-temperature drying process (at temperatures between 0 and 20 ) when ultrasound was applied. Contents of the research In Chapter 1, the effects of different freezing pre-treatments (at 20 C, at 80 C and by liquid nitrogen immersion) on the hot-air drying kinetics (at 50 C), microstructure and quality parameters of three vegetal products with different initial microstructure (beetroot, apple and eggplant), were studied. In Chapter 2, the effects of both freezing (at 20 C) prior to drying and the ultrasound assistance during drying (at acoustic power densities of 16.4 and 26.7 kW/m3) on the drying kinetics (at 40 C), microstructure and quality parameters of beetroot were evaluated. Finally, in Chapter 3, the effects of the ultrasound application (at acoustic power density of 20.5 kW/m3) on the low-temperature drying kinetics (at 5, 10 and 15 C), microstructure and quality parameters of kiwifruit and mushroom were evaluated. Conclusion In Chapter 1, freezing pre-treatment promoted higher changes on high porosity products (eggplant and apple) than in low porosity products (beetroot). Thus, higher drying rate enhancement and quality parameters losses were observed in eggplant and apple than in beetroot. With regard to the different freezing pre-treatments studied, freezing by liquid nitrogen immersion seemed to promote minor structure damage, less drying rate enhancement and quality parameters losses probably due to its fast freezing rate and small crystals formation. Meanwhile, freezing pre-treatments at 20 and 80 °C could not be distinguished among themselves in analysed parameters due their slow and similar freezing rates. In Chapter 2, freezing pre-treatment and ultrasound application enhanced beetroot drying but important changes in microstructure, bioactive compounds contents and antioxidant activity were promoted although drying time shortening preserved betalain contents in some cases. In Chapter 3, although the rise of the drying temperature from 5 to 15 ºC promoted higher kiwifruit and mushroom quality parameters losses, the use of ultrasound at 15 ºC allowed to obtain a shorter drying kinetic and better maintained the final bioactive compounds contents and antioxidant activity.
[spa] Introducción El proceso de secado se aplica en frutas y verduras para reducir el contenido en humedad, fundamentalmente con el objetivo de alargar su vida útil. Sin embargo, el secado convectivo provoca pérdidas en la calidad del producto debido a la degradación térmica y la exposición al aire. Para intensificar el proceso de secado convectivo, es este trabajo se han utilizado el pretratamiento por congelación y los ultrasonidos de potencia durante el secado, con el objetivo de reducir el tiempo de secado, y preservar la calidad del producto. Por tanto, los dos objetivos generales de este trabajo fueron, por una parte, el estudio de la intensificación del proceso de secado a temperaturas superiores a 20 C mediante pretratamientos de congelación y aplicación de ultrasonidos durante el secado y, por otra parte, el estudio también de la intensificación del secado a baja temperatura (a temperaturas entre 0 y 20 C) mediante la aplicación de ultrasonidos durante el secado. Contenido de la investigación En el Capítulo 1, se presenta el efecto de diferentes pretratamientos de congelación (a 20 C, a 80 C y por inmersión en nitrógeno líquido) sobre las cinéticas de secado convectivo a 50 C, la microestructura y los parámetros de calidad de tres matrices vegetales con diferente microestructura inicial (remolacha, manzana y berenjena). En el Capítulo 2, se evaluaron los efectos de la congelación (a 20 C) previa al secado y de la asistencia acústica durante el secado (a densidades de potencia acústica de 16.4 y 26.7 kW/m3) sobre las cinéticas de secado (a 40 C), la microestructura y los parámetros de calidad de la remolacha. Finalmente, en el Capítulo 3, se evaluaron los efectos de la aplicación de ultrasonidos (a una densidad de potencia acústica de 20.5 kW/m3) sobre el secado a baja temperatura (a 5, 10 y 15 C), la microestructura y los parámetros de calidad de kiwi y champiñón. Conclusión En el Capítulo 1, el pretratamiento de congelación provocó mayores cambios en productos de alta porosidad (berenjena y manzana) que en productos de baja porosidad (remolacha). Por tanto, se observó un mayor incremento en la velocidad de secado y mayores pérdidas en los parámetros de calidad en berenjena y manzana que en remolacha. En cuanto a los diferentes pretratamientos de congelación estudiados, la congelación por inmersión en nitrógeno líquido provocó menor daño en la estructura, menor incremento de la velocidad de secado y menores pérdidas en los parámetros de calidad probablemente debido a su rápida velocidad de congelación y a la formación de cristales de pequeño tamaño. Asimismo, los pretratamientos a 20 C y a 80 C no pudieron ser diferenciados entre sí en los parámetros analizados debido a sus lentas y similares velocidades de congelación. En el Capítulo 2, el pretratamiento de congelación y la aplicación de ultrasonidos aceleraron el secado de remolacha, pero se produjeron importantes cambios en la microestructura, los contenidos en compuestos bioactivos y la actividad antioxidante, si bien la reducción del tiempo de secado preservó los contenidos en betalainas en algunos casos. En el Capítulo 3, aunque el aumento de la temperatura de secado de 5 a 15 C provocó mayores pérdidas de los parámetros de calidad de kiwi y champiñón, la aplicación de ultrasonidos a 15 C permitió obtener una cinética de secado más corta, y se conservaron mejor los contenidos en compuestos bioactivos y la actividad antioxidante
[cat] El procés d’assecat s’utilitza en fruites i verdures per a reduir el contingut en humitat, fonamentalment per allargar d’aquesta manera la seva vida útil. Però l’assecat convectiu provoca pèrdues en la qualitat del producte a causa de la degradació tèrmica i de l’exposició a l’aire. Per a intensificar el procés d’assecat convectiu, en aquest treball, s’han utilitzat el pretractament de congelació i l’aplicació d’ultrasons de potència durant l’assecat amb l’objectiu de reduir el temps d’assecat i preservar la qualitat del producte. Conseqüentment, els dos objectius generals d’aquest treball foren, d’una banda, l’estudi de la intensificació del procés d’assecat a temperatures superiors a 20  mitjançant pretractaments de congelació i aplicació d’ultrasons durant l’assecat i, per l’altra, l’estudi també de la intensificació de l’assecat a baixa temperatura (a temperatures entre 0 i 20 ) mitjançant l’aplicació d’ultrasons durant l’assecat. Continguts de la investigació En el Capítol 1, es presenten els efectes de diferents pretractaments de congelació (a 20 C, a 80 C i per immersió en nitrogen líquid) en les cinètiques d’assecat convectiu a 50 C, la microestructura i els paràmetres de qualitat de tres matrius vegetals amb diferent microestructura inicial (remolatxa, poma i albergínia). En el Capítol 2, s’avaluaren els efectes de la congelació (a 20 ºC) prèvia a l’assecat i l’assistència per ultrasons durant l’assecat (a densitats de potència acústica de 16.4 i 26.7 kW/m3) en les cinètiques d’assecat (a 40 C), la microestructura i els paràmetres de qualitat de la remolatxa. Finalment, en el Capítol 3, s’avaluaren els efectes de l’aplicació d’ultrasons (a una densitat de potència acústica de 20.5 kW/m3) en l’assecat a baixa temperatura (a 5, 10 i 15 C), la microestructura i els paràmetres de qualitat de kiwi i xampinyó. Conclusió En el Capítol 1, el pretractament de congelació va provocar majors canvis en productes d’alta porositat (albergínia i poma) que en productes de baixa porositat (remolatxa). Per tant, es va observar un major increment en la velocitat d’assecat i majors pèrdues en el paràmetres de qualitat en albergínia i poma que en remolatxa. Quant als diferents pretractaments de congelació estudiats, la congelació per immersió en nitrogen líquid va provocar menor dany en l’estructura, menor increment de la velocitat d’assecat i menors pèrdues en el paràmetres de qualitat probablement degut a la seva ràpida velocitat de congelació i a la formació de cristalls de mida petita. Així mateix, els pretractaments a 20 C i a 80 C no es pogueren distingir entre sí en els paràmetres analitzats a causa de les seves lentes i similars velocitats de congelació. En el Capítol 2, el pretractament de congelació i l’aplicació d’ultrasons acceleraren l’assecat de remolatxa, però es produïren importants canvis en la microestructura, els continguts en composts bioactius i l’activitat antioxidant, tot i que la reducció del temps d’assecat va preservar els continguts en betalaines en alguns casos. En el Capítol 3, tot i que l’augment de la temperatura d’assecat de 5 a 15 C va provocar majors pèrdues en els paràmetres de qualitat de kiwi i xampinyó, l’aplicació d’ultrasons a 15 C va permetre obtenir una cinètica d’assecat més curta i es mantingueren millor els continguts en composts bioactius i l’activitat antioxidant.

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Tom, Ahmat. "Contribution au séchage solaire des produits carnés : Modélisation et réalisation d'un séchoir adapté aux pays tropicaux." Thesis, Paris, ENSAM, 2015. http://www.theses.fr/2015ENAM0013/document.

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La présente étude porte sur la modélisation à l'échelle du produit, puis à l'échelle du procédé, des transferts de chaleur et de matière, au cours du séchage solaire de viande de bœuf, et entre ce produit et son environnement. A l'échelle du produit, les isothermes de désorption et cinétiques de séchage de la viande de bœuf sont déterminées expérimentalement, puis modélisées afin de caractériser la viande sur le plan hygroscopique et de prédire son comportement au cours du séchage. L'étude et la modélisation du comportement hygroscopique permet de passer à une échelle du procédé par la mise en place d'un modèle de séchage solaire de la viande de bœuf adapté à un séchoir solaire, conçu et réalisé pour le séchage des produits carnés dans un contexte tropical (séchoir solaire de Kilichi). Le modèle est validé par des essais expérimentaux menés dans un contexte tropical (N'Gaoundéré-Cameroun). L'impact du séchage solaire sur la qualité du produit est étudié à travers des analyses microbiologiques et biochimiques effectuées sur des échantillons de viande de bœuf séchés, à l'échelle du laboratoire, dans un séchoir solaire conçu et réalisé pour une bonne maitrise des paramètres de séchage solaire. Les analyses microbiologiques montrent que l'impact du rayonnement solaire sur la destruction des microorganismes est plus significatif que celui de la température de séchage. Les analyses biochimiques montrent que le séchage induit une forte oxydation des lipides mais n'a pas d'impact sur la teneur en lipide de la viande
This study deals with the modeling of heat and mass transfers during solar drying of beef, and between this product and its environment, at the scale of the product and thereafter at the scale of the process. At the scale of the product, desorption isotherm and drying kinetics of fresh beef were determined and modeled to characterize and predict the hygroscopic behavior of the beef during its drying. At the scale of the process, we proposed a model of solar drying of beef, adapted to a solar dryer that was designed and manufactured for the solar drying of beef in tropical environment (Solar dryer of Kilichi). This model was validated by experimental tests conducted in situ, in a tropical country (Cameroon- N'gaoundéré). The impact of solar drying on the quality of the product was investigated through microbiological and biochemical analyzes conducted on beef samples, dried at the laboratory with a solar dryer that was designed and manufactured to obtain a good control of solar drying parameters. These analyzes showed that the impact of solar radiation on the destruction of microorganisms is more significant than that of the drying temperature. Biochemical analysis showed that drying induces a severe lipid oxidation but has no impact on the lipid content of the meat

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Kurozawa, Louise Emy 1980. "Efeito das condições de processo na cinetica de secagem de cogumelo (Agaricus blazei)." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256333.

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Orientador: Fernanda Elizabeth Xidieh Murr
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Mestrado
Mestre em Engenharia de Alimentos

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Eriksson, Anders. "Energy efficient storage of biomass at Vattenfall heat and power plant." Thesis, Institutionen för energi och teknik, SLU, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-153326.

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Storage of biomass is often associated with problems such as heat development, drymatter losses and reduction of fuel quality. The rise in temperature can potentiallycause a risk of self-ignition in the fuel storage. Moreover, emissions from storage pilescan cause health problems in the surrounding. The dry matter losses and reduction offuel quality can have economical effects. The aim of this thesis project is to developguidelines on how to store large amount of biomass at Vattenfalls heat and powerplants in an optimal way. Storage trials at Idbäckens CHP were done in order to studythe effect of storage on fuel quality, dry matter losses and temperature development.Two storage trials were performed over six weeks with waste wood chips and stemwood chips stored in about 4.5 m high outdoor piles. A trial over four days in whichwaste wood chips was placed on a heated surface was evaluated. A study to test thepossibility of using waste heat to dry waste wood chips was performed.Small but not negligible dry matter losses were observed in both of the piles of storedmaterial. The largest weekly losses were found during the first week of storage and adeclining behavior could thereafter be seen. The accumulated losses during six weeksof storage were 2.0 % and 1.7 % respectively, for waste wood and stem wood. Storageduring six weeks of waste wood and newly chipped stem wood did not cause anymajor deterioration of the fuel quality as such, beside the substance losses.No drying effect could be seen in the heated surface trial. The surface became warm,about 50°C, but it was not sufficient to dry the chips. The conclusion is that it is notpossible to dry large amount of chips on a heated surface with the design used hereand during four days.The overall conclusion is that in order to minimize the dry matter losses the materialshould be handled according to the LIFO (last in first out) principle. Wheneverpossible, try to purchase fuel that has been stored for a while since the more easilydegraded compounds has already been degraded through microbial activity. There is apossibility that the largest losses has already occurred. Furthermore, try also tocomminute the material (reduce the particle size) at the plant and as close in time tocombustion as possible.

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Camargo, Gisele Anne. "Novas tecnologias e pre-tratamentos : tomate seco embalado a vacuo." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255534.

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Orientador: Roberto Herminio Moretti
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: A concentração osmótica e outros pré-tratamentos visam melhorar a qualidade do produto e otimizar o processo de secagem. Dentre estes tratamentos pode-se citar o uso de antioxidantes para evitar o escurecimento excessivo e manter as características nutricionais. A incorporação de concentrado de tomate com 18 a 36 oBrix, não é um método utilizado na fabricação de tomates secos, e foi um procedimento utilizado com o objetivo de melhorar a qualidade e aumentar o rendimento do processo de secagem. E ainda a utilização de ácidos fracos em soluções utilizadas em desidratação ou concentração osmótica representa uma alternativa de processamento brando. Os objetivos gerais desta pesquisa foram: avaliar e selecionar novas tecnologias e pré-tratamentos, visando melhorar a qualidade do produto final e também aumentar o rendimento e eficiência do processo de secagem de tomate para conserva; e definir e caracterizar a vida de prateleira do produto selecionado. Esta pesquisa definiu procedimentos que permitiram aumentar a eficiência e qualidade de um novo produto: tomates secos, embalados a vácuo com umidade intermediária e com segurança ao consumidor. Foi observado que a utilização de açúcares invertidos permitem maior perda de água e entrada de sólidos no tomate. O ácido ascórbico mostrou perda nos primeiros 30 minutos de pré-tratamento osmótico. O conteúdo de licopeno aumentou a disponibilidade nos primeiros 10 minutos com posterior decréscimo gradual. Os consumidores determinaram que o sabor é o fator mais importante na aceitação do produto e desaprovaram a aplicação de concentrado triplo de tomate como pré-tratamento à secagem. A aplicação de antioxidante (metabissulfito de sódio e ácido isoascórbico) anterior à secagem com ar forçado proporcionou maiores teores de ácido ascórbico e licopeno no produto final. A relação ¿Sólidos Solúveis/Acidez Total¿ escolhida pelo paladar dos consumidores foi de 23,8 a 26,65. A melhor eficiência do pré-tratamento osmótico (solução mista de sacarose e açúcares invertidos) foi obtida quando adicionado sal entre os valores de 5,05 a 7,45% e ácido cítrico entre os limites de 6,62 -7,25%. A preferência sensorial do consumidor foi para os produtos obtidos a partir de concentração osmótica em solução com 65º Brix, com a adição de 5,85% de NaCl e 6,00% de ácido cítrico. A qualidade microbiológica do tomate seco embalado a vácuo foi mantida durante o período avaliado de 180 dias para refrigerado e 90 dias em temperatura ambiente. A construção de isotermas permitiu observar que o armazenamento em umidade relativa superior a 50% proporciona a adsorção de água ao produto, alterando as características originais do tomate seco. Os tomates desidratados osmoticamente com açúcares invertidos, sal é ácido cítrico proporcionaram atividades de água entre 0,76 a 0,86. A reconstituição e reutilização do xarope foi um procedimento eficiente no processo produtivo
Abstract: Osmotic concentration and other pre-treatments aim to improve product quality and optimise the drying process. Amongst these treatments one can mention the use of antioxidants to avoid excessive browning and maintain the nutritional characteristics. The incorporation of tomato concentrate at 18 to 36°Brix is not a method currently used in the manufacture of dried tomatoes, but could be a suitable method for quality improvement as well as increasing the yield on drying, considering that it would add up to six times the amount of soluble solids naturally present in the tomato. And the use of weak acids in the solutions used for osmotic drying or concentration represents a mild processing alternative, resulting in a product with appropriate sensory characteristics for immediate consumption. The use of a combination of additives together with various types of sugar (sucrose, fructose and glucose), especially acidifiers, in addition to their antioxidant action, help to increase the rate of osmosis. The general objectives of this research were: to evaluate and select new technology and pre-treatments aiming at improving final product quality and process yield and efficiency in the drying of tomato, and also to define and characterise the shelf life of the selected product. This research defined procedures, which allowed for an increase in efficiency and quality of a new product: vacuum-packed dried tomato with intermediate moisture content, safe for consumption. The use of invert sugar was shown to increase the efficiency of the osmotic dehydration of tomatoes, and temperatures above 45°C failed to provide the desired quality. Ascorbic acid showed losses during the first 30 minutes of pre-treatment, and the lycopene showed an increase in availability during the first 10 minutes, followed by a gradual decrease. The consumers determined that flavour was the most important factor for product approval and disapproved the application of triple concentrated tomato paste. The application of antioxidant (sodium metabisulphite and isoascorbic acid) allowed for greater retention of the lycopene and ascorbic acid. The consumers preferred products with the ¿soluble solids/total acidity ratio¿ between 23.8 and 26.65. The salt concentration in the mixed syrup of sucrose and invert sugar was shown to be more efficient in the osmotic dehydration process between the values of 5.05 and 7.45%, with a citric acid concentration between 6.62 and 7.25%. The consumers chosen (sensory analysis) products obtained from pre-treatment: osmotic dehydration in 65°Brix syrups with the addition of 5.85% NaCl and 6.00% citric acid. The microbiological quality of the product, vacuum-packed dried tomato, was maintained during the periods evaluated of 180 days under refrigeration and 90 days at room temperature. The consumers considered values for the color parameter ¿L¿ above 38.37 as unacceptable, indicating this value as an instrumental colour limit (luminosity). The dried tomato adsorbed water in Relative Humidity to up 50%. The dried tomatoes osmotically dehydrated with invert sugar, salt and citric acid, provided values for water activity the 0.76 to 0.86. The syrup could be reused efficiently
Doutorado
Tecnologia de Alimentos
Doutor em Tecnologia de Alimentos

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Orellana, Adrian Santiago Bermeo. "Influencia de la temperatura del aire de secado en la cantidad y composición de aceite esencial de Cordia verbenacea." Universidade Federal de Viçosa, 2014. http://locus.ufv.br/handle/123456789/3655.

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The Cordia verbenacea species, known as Erva Baleeira has been mostly studied by its pharmacologic properties since it has a curative potential as an anti-inflammatory, an analgesic, and an anti-ulcer gene; however, the effect of the drying process on this species has not been analyzed yet. The main purpose of this work was to evaluate the influence of the drying air temperature in the quantity and quality of the cordia s essential oil; therefore, in order to reach that objective, some leaves of this plant species were collected during august of 2013 from the Experimental Vale do Piranga farm, which belongs to EPAMING. Consequently, the vegetal material was carefully selected and dried. The stablished temperatures for that process were 40, 50, 60, and 70 Celsius degrees, with the aim of evaluating the quantity and quality of the essential oil obtained from dried leaves compared to fresh leaves oil. A Clavenger type apparatus was used for the essential oil extraction from cordia leaves and afterward, the appropriate gas-chromatographic analysis was performed (GC-MS-GCFID). In summary, the results of the study allow one to conclude that the content of the cordia s essential oil was affected by the drying air temperatures while the one obtained from fresh leaves remained unaltered. In addition, between all the active principles found, only α- humulene had a deducted concentration due to the influence of the drying process compared to the fresh plant.
La especie Cordia verbenacea, conocida como Erva Baleeira , ha sido objeto de estudio por sus propiedades farmacológicas, confirmándose su potencial como anti-inflamatorio, analgésico, e anti-ulcero génico, sim embargo aún no se ha estudiado el efecto que tiene el proceso de secado en esta especie. El objetivo de este trabajo fue evaluar la influencia que tiene la temperatura del aire de secado en la cantidad y calidad de aceite esencial de cordia, para cumplir dicho objetivo, hojas de esta especie fueron obtenidas de un cultivo de la hacienda Experimental Vale do Piranga, perteneciente a EPAMIG, en el mes de agosto del 2013, posteriormente el material vegetal fue seleccionado y llevado al secado. Las temperaturas establecidas fueron de 40, 50, 60 y 70 °C y de esta manera evaluar la cantidad y calidad del aceite esencial obtenido de hojas secas en comparación con el aceite obtenido de muestras frescas. En la extracción de aceite esencial de hojas de cordia, se usó un aparato tipo Clevenger y posteriormente se realizó el respectivo análisis cromatografico a gas (GC-MS GCFID). Puede concluirse que el contenido de aceite esencial fue afectado por las temperaturas del aire de secado, respecto al aceite esencial obtenido de hojas frescas y que dentro de los principios activos encontrados, solamente el α-humulene tuvo su concentración disminuida por influencia del proceso de secado cuando comparado con la planta fresca.

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SILVA, Ezequiane Machado da. "Obtenção e caracterização do extrato seco Padronizado de Vernonanthura ferruginea (LESS.) H. Rob., Asteraceae (Assa-Peixe)." Universidade Federal de Goiás, 2011. http://repositorio.bc.ufg.br/tede/handle/tde/2107.

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Vernonanthura ferruginea (Less.) H. Rob. (Asteraceae), a typical plant of the Brazilian savannah, popularly known as assa-peixe, presented analgesic, antiedematogenic, antioxidant and antiulcer activities in scientific studies. But in literature there are no works related to the production of dried extracts of this plant species. In this work, standardized spray-dried extracts of V. ferruginea were obtained. The work started with the obtainment and characterization powder of the leaves of the V. ferruginea. A hydroalcoholic extract was obtained by percolation using as solvent ethanol 95 % (v/v). The drying experiments followed a 23 + 2 factorial design. The influence of several in-process parameters e. g. extract feed rate, drying air inlet temperature and drying adjuvant ratio, on the dried extracts properties were investigated. The properties investigated were process yield, residual moisture, water activity, total triterpenes content and lupeol content. The lupeol, triterpene related to several pharmacological activities (anti-inflammatory, anticancer, antiulcer, etc), was first time isolated in this species and was used as chemical marker in High Performance Liquid Chromatography (HPLC) quantification assays in all steps of this work. In this way an analytical methodology was validated following Agência Nacional de Vigilância Sanitária (ANVISA Brazilian National Health Surveillance Agency) guidelines. This methodology proved to be selective, linear, sensible, precise, accurate and robust. On the herbal raw material characterization, preliminary phytochemical screening was performed, which confirmed the presence of tannins, flavonoids, triterpenes, saponins, resins and mucilage. Was also observed a mean powder size of 398.97 ± 6.91 μm, as well as moisture, total triterpenes and lupeol contents of 8.25 ± 0.57%, 2.49 ± 0.16% and 0.17 ± 0.01%, respectively. The concentrated hydroalcoholic extract presented density of 0.8364 ± 0.0015 g/mL, solids content of 6.70 ± 0.19%, pH 5.81 ± 0.05, alcoholic content of 87.08 ± 0.80% and a viscosity of 4.93 ± 0.0416 mPas. The levels of total triterpenes and lupeol contents were 22.57 ± 0.94 and 4.31 ± 0.01%, respectively. Results showed drying yields ranging from 10.47 to 30.82%. Also, all dried products showed moisture contents and water activities below 5% and 0.5, respectively. Analysis of variance (ANOVAs) proved that all factors and some of their interactions significantly affected the levels of total triterpenes and lupeol contents. Moreover, the selected condition for obtaining dry extracts of V. ferruginea with adequate physicochemical properties is the one performed with the higher colloidal silicon dioxide ratio (20%), the lower extract feed rate (4mL/min) and the lower drying air inlet temperature (80°C), in which it was obtained levels of total triterpenes and lupeol contents of 7.65 ± 0.27% and 2.47 ± 0.04%, respectively. The dry extract obtained in this condition show high content of spherical particles and its antiulcer activitie in model of ulcer induced by indomethacin was proved. Comparison of powder, hydroalcoholic and dry extract chromatographic (TLC) show that the hydroalcoholic extraction was selective for the extraction of lupeol against other major terpenes and the drying process did not cause changes in the chemical profile of the extract with respect to these substances. Thus, the spray drying can be an attractive e and promising alternative for the development of V. ferruginea phytomedicines.
Vernonanthura ferruginea (Less.) H. Rob. (Asteraceae), planta típica do cerrado brasileiro, conhecida popularmente como assa-peixe, demonstrou atividade analgésica, antiedematogênica, antioxidante e antiulcerogênica em estudos científicos. Porém, na literatura consultada não existem trabalhos relacionados à produção de extratos secos desta espécie vegetal. A obtenção de extratos secos padronizados de V. ferruginea, por meio da técnica de spray drying iniciou-se pela obtenção e caracterização do material de partida (pó das folhas da planta) e a partir deste, obteve-se o extrato hidroalcoólico pelo método de percolação usando como líquido extrator etanol a 95% (v/v). Os experimentos de secagem foram conduzidos seguindo um planejamento fatorial do tipo 23 + 2 a fim de investigar as influências de alguns parâmetros envolvidos no processo, e. g. fluxo de alimentação de extrato, temperatura de entrada do ar de secagem e proporção de adjuvante de secagem nas propriedades dos extratos secos obtidos, tais como rendimento do processo, umidade residual, atividade de água, teor de triterpenos totais e teor de lupeol. O lupeol, triterpeno relacionado à diversas atividades farmacológicas (antiinflamatória, antitumoral, antiulcerogênica, etc), foi isolado pela primeira vez nesta espécie e selecionado como marcador químico de todas as etapas do processo. Para tanto, foi validado um método analítico por Cromatografia Líquida de Alta Eficiência (CLAE) seguindo os parâmetros e critérios de aceitação propostos pela Agência Nacional de Vigilância Sanitária (ANVISA), o qual provou ser seletivo, linear, sensível, preciso, exato e robusto. Na caracterização do pó das folhas, foi realizada prospecção fitoquímica preliminar onde foi constatada a presença de taninos, flavonóides, triterpenos, saponinas, resinas e mucilagens. Foram verificados teores de voláteis, triterpenos totais e lupeol que apresentaram valores de 8,25 ± 0,57%, 2,49 ± 0,16% e 0,17 ± 0,01%, respectivamente, além de tamanho médio de partículas de 398,97 ± 6,91 μm. O extrato hidroalcoólico apresentou densidade 0,8364 ± 0,0015 g/mL, resíduo seco de 6,70 ± 0,19%, pH 5,81 ± 0,05, teor alcoólico de 87,08 ± 0,80% e viscosidade de 4,93 ± 0,0416 mPas. Ainda foram obtidos teores de triterpenos totais e lupeol de 22,57 ± 0,94% e 4,31 ± 0,01%, respectivamente. Os rendimentos de secagem variaram de 10,47 a 30,82%, sendo que em todos os produtos secos, foram observados teores de voláteis e atividade de água abaixo de 5% e 0,5, respectivamente. Análises de Variância (ANOVA) demonstraram que todos os fatores e algumas de suas interações afetaram significativamente o teor de triterpenos totais e o teor de lupeol no pó, sendo que a condição selecionada para ser empregada na obtenção de extratos secos padronizados de assa-peixe com propriedades físico-químicas adequadas foi aquela realizada com maior proporção de dióxido de silício coloidal (20%), menor vazão de extrato de alimentação (4mL/min) e menor temperatura do ar de secagem (80°C), na qual obteve-se teores de triterpenos totais e lupeol de 7,65 ± 0,27% e 2,47 ± 0,04%, respectivamente. O extrato seco obtido nestas condições apresentou alta proporção de partículas esféricas e a sua atividade antiulcerogênica no modelo de úlceras induzidas por indometacina foi comprovada. A comparação do perfil cromatográf ico (CCD) do pó, do extrato hidroalcoólico e do extrato seco demonstrou que a extração hidroalcoólica foi seletiva para a extração de lupeol em relação a outros terpenos majoritários e o processo de secagem não ocasionou alterações no perfil químico do extrato em relação a estas substâncias. Assim, a técnica de spray drying pode ser uma alternativa atrativa e promissora para o desenvolvimento de fitoterápicos de V. ferruginea.

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Johansson, Niklas. "Uttorkning av betong : inverkan av cementtyp, betongkvalitet och omgivande fuktförhållanden = Drying of concrete : effect of cement type, concrete quality and outer moisture conditions /." Lund : Avd. Byggnadsmaterial, Lunds tekniska högskola, Univ, 2005. http://www.byggnadsmaterial.lth.se/.

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Van, Zyl Tinake. "The effect of partial rootzone drying and foliar nutrition on water use efficiency and quality of table grape cultivars Crimson seedless and Dauphine." Thesis, Link to the online version, 2007. http://hdl.handle.net/10019/1279.

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Maurer, Claudia Christine [Verfasser]. "Drying of biogas digestate in a hybrid waste-heat/solar dryer and the effect on nitrogen emissions and fertilizer quality / Claudia Christine Maurer." Düren : Shaker, 2020. http://d-nb.info/1222396289/34.

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Maurer, Claudia [Verfasser]. "Drying of biogas digestate in a hybrid waste-heat/solar dryer and the effect on nitrogen emissions and fertilizer quality / Claudia Christine Maurer." Düren : Shaker, 2020. http://nbn-resolving.de/urn:nbn:de:101:1-2020112904252033907640.

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Ferreira, Alisson Luís Bach. "Desempenho de secadores contínuos operando em sistema intermitente." Universidade Federal de Pelotas, 2006. http://repositorio.ufpel.edu.br/handle/ri/1462.

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The objective of this study was to evaluate the performance of five continuous dryers, of different manufacturers, operating in an intermittent system and drying maize. Three tests in each dryer were carried out and the results of each test were analyzed independently and compared as an experiment, since each test does not characterize a repetition. The initial moisture of the product was different for each test performed. For the evaluation of the physical quality of the product, the iodine coloration drying test was used. To evaluate the energy efficiency of the system, the consumption of both fuel and electric power was measured. Taking into account the conditions in which the tests were realized, it was possible to observe that the drying speed of the maize seeds in continuous dryers operating in an intermittent system may range from two to three percent points per hour, at drying air temperatures ranging from 80°C to 120°C; the physical quality of the product, dried in dryers whose drying temperatures suffered variations in a higher level, is relatively inferior to that of the product submitted to drying at lower levels of temperature variation.
O objetivo deste estudo foi avaliar o desempenho de cinco secadores contínuos, de diferentes fabricantes, operando em sistema intermitente e secando milho. Foram realizados três testes em cada secador e os resultados de cada teste foram analisados independentemente e comparados como um experimento, uma vez que cada teste não caracteriza uma repetição. A umidade inicial do produto foi diferente para cada teste realizado. Para avaliação da qualidade física do produto foi realizado o teste de coloração com tintura de iodo. Para avaliação da eficiência energética do sistema, mediu-se o consumo de combustível e de energia elétrica. Levando em consideração as condições em que foram realizados os testes, foi possível observar que a velocidade de secagem de sementes de milho em secadores contínuos operando em sistema intermitente pode atingir dois a três pontos percentuais por hora, com o emprego de temperaturas do ar de secagem de 80 a 120 °C; a qualidade física do produto secado em secadores cujas temperaturas de secagem sofreram maiores variações, é inferior relativamente a do produto submetido à secagem com menores variações de temperatura.

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Gomes, Lúcio Marçal. "Efeito de diferentes técnicas de secagem na qualidade do café arábica (Coffea arábica L.) em Timor Leste." Master's thesis, Universidade de Évora, 2014. http://hdl.handle.net/10174/10962.

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Uma vez que o café é uma das principais receitas de Timor-Leste e o primeiro produto agrícola a garantir o rendimento a cerca de um quarto da população, julgou-se ser interessante observar e caracterizar a produção do café Arábica de Ermera, e avaliar os efeitos de aplicação de diferentes tecnologias no processo de secagem para melhorar a sua qualidade na Cooperativa Café Timor. Na primeira parte do trabalho, aborda-se directamente o objectivo de identificar e caracterizar as actividades relacionadas com o sistema de produção de café na Cooperativa e na Empresa supramencionadas, incidindo especialmente sobre o processo de secagem do café. Seguidamente, a partir de Abril de 2012, efectuou-se um trabalho experimental composto por duas experiências: Experiência 1. Efeito da cor da lona na qualidade do café arábica de Timor; Experiência 2. Efeito do tempo de fermentação na qualidade do café arábica de Timor; Estes ensaios foram desenvolvidos em Timor-Leste, juntos locais de produção da Cooperativa Café Timor (CCT). Após a realização do trabalho experimental, procedeu-se ao tratamento e análise de dados, apresentação de resultados e sua discussão. Os resultados desta pesquisa indicam que a cor da lona tem uma influência significativa no temperatura e teor de água dos grãos de café ao longo do processo de secagem levando a lona preta a temperaturas mais elevadas e menores teores de água do que as lonas de cor branca ou azul. O tempo de fermentação só teve uma influência significativa na acidez do café, onde se verificou que maiores tempos de fermentação originam uma acidez mais elevada. Deste modo recomenda-se que estes aspectos sejam levados em conta no tratamento pós-colheita dos grãos de café arábica de Timor; **** ABSTRACT: Once the coffee is a major in revenue Timor-Leste and the first crop to ensure income to about a quarter of the population, it was thought to be interesting to observe and characterize the production of Arabica coffee in Ermera District, and evaluate the application effects of different technologies in coffee drying process in order to improve its quality in Cooperative Café Timor (CCT). In the first part of the work, the objective of identifying and characterizing the activities related to the system of coffee production in the Cooperative and Company above mentioned are directly addressed, by focusing on the process of drying coffee. From April 2012, we performed an experimental study that consisted of two experiments: Experiment 1. The effect canvas colour on the quality of Arabica coffee in Timor-Leste; Experiment 2. The effect of fermentation time on the quality of Arabica coffee in Timor-Leste; These experiments were developed in Timor-Leste, together local production of CCT. After completion of the experimental work, data treatment and analysis, presentation of results and discussion was performed. These results indicate that canvas colour has a significant influence on the temperature and water content of coffee beans throughout the drying process, leading black canvas to higher temperatures and lower water contents than the white or blue colour canvas. The fermentation time, so, had a significant influence on the acidity of the coffee, where longer fermentation times originate a higher acidity. Thus, it is recommended that these aspects be taken into account in postharvest treatment of Arabica coffee beans from Timor-Leste.

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Francescato, Leandro Nicolodi. "Equisetum giganteum l. : parâmentros de controle de qualidade, análise química e desenvolvimento de extrato seco por spray drying." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/139443.

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As partes aéreas de Equisetum giganteum L. (Equisetaceae), espécie nativa da América do Sul, denominada cavalinha e rabo-de-cavalo, são utilizadas popularmente sob a forma de infuso ou decocto no tratamento de afecções urinárias e hepáticas e principalmente como diurética, hemostática, adstringente, remineralizante e emagrecedora. Entretanto, poucos estudos científicos foram realizados envolvendo esta espécie. Quanto às propriedades biológicas de seus extratos, têm sido relatadas atividades diurética e antimicrobiana, e ausência de efeitos tóxicos agudos em camundongos, quando administrados por via oral. Considerando a ampla disponibilidade de E. giganteum no mercado brasileiro e o seu potencial terapêutico, torna-se necessária a definição de parâmetros de controle de qualidade para a matéria-prima vegetal, bem como o desenvolvimento de produtos padronizados. Assim, este trabalho objetivou avaliar parâmetros de controle de qualidade e estabelecer critérios químicos que permitam diferenciar E. giganteum de outras espécies do gênero e, a partir de uma solução extrativa aquosa, desenvolver extrato seco por spray drying e caracterizá-lo. Para isso, partes aéreas de E. giganteum e outras espécies disponíveis foram utilizadas. Análises comparativas destas amostras foram realizadas por CCD, CLAE e teor de flavonóides totais. Para E. giganteum, o teor de cinzas, os constituintes fenólicos e flavonóides totais foram determinados por método espectrofotométrico no UV/VIS. Análise por CCD foi realizada em placas de gel de sílica; fase móvel acetato de etila:ácido fórmico:ácido acético glacial:água (100:11:11:26); e detecção com reagente Natural / UV a 365 nm. Análises por CLAE dos extratos metanólicos foram realizadas empregando coluna de fase-reversa (C18) e detector de arranjo de diodos. O material vegetal foi também submetido à hidrólise ácida, a qual foi otimizada empregando Desenho Composto Central Rotacional e Análise de Superfície de Resposta para investigar os efeitos da concentração de HCl e do tempo de hidrólise. As agliconas correspondentes aos flavonóides heterosídicos foram extraídas e analisadas por método de CLAE previamente validado. O teor de flavonóides totais foi avaliado por ensaio colorimétrico com cloreto de alumínio a 425 nm. Análises por CLAE-DAD e CLAE-EM/EM também foram realizadas na intenção de caracterizar os compostos fenólicos presentes em E. giganteum. Uma solução extrativa aquosa foi obtida por decocção a partir da matéria-prima vegetal e posteriormente seca por spray drying empregando equipamento NIRO® atomizer semi-industrial. O extrato seco obtido foi então caracterizado. Os resultados demonstraram para E. giganteum um teor de cinzas totais e insolúveis em ácido (a 600ºC) respectivamente de 20,07 ± 0,21% e 13,75 ± 0,39%. O teor de fenólicos totais foi de 7,27 ± 0,05 mg equivalente a ácido gálico por grama, e de 0,420 ± 0,014 g% para os flavonóides totais. Na análise por CCD de E. giganteum foi verificada a presença de manchas características de polifenóis, sendo que, na análise por CLAE, alguns constituintes apresentaram espectro de UV característicos de derivados do ácido cinâmico e do canferol A diferenciação entre E. giganteum e E. arvense, e em menor extensão para E. hyemale e E. bogotense, foi possível através do perfil cromatográfico obtido nas análises por CCD e CLAE. A possível presença de tiamina foi caracterizada por CCD nestas amostras. Nas condições ótimas de hidrólise determinadas para E. giganteum, canferol e, em menor teor, quercetina foram encontradas. A análise comparativa das agliconas dos flavonóides por CLAE e dos flavonóides totais por espectrofotometria revelou similaridades químicas entre E. giganteum, E. hyemale e E. bogotense, mas não para E. arvense, o qual apresentou um perfil de agliconas distinto. A maior parte dos compostos fenólicos puderam ser caracterizados em E. giganteum por meio da análise por CLAE-EM/EM, sendo encontrado principalmente derivados heterosídicos do canferol, mas também outros compostos fenólicos raros. A obtenção de extrato seco por spray drying a partir de solução extrativa aquosa de E. giganteum mostrou-se viável, com alto rendimento do processo (85,6%). O produto foi caracterizado como um pó fino com baixa densidade, baixa fluidez e alta umidade residual, mas baixa atividade de água. Com relação a sua composição química, o extrato seco apresentou alto teor de minerais e açúcares redutores. A presença na droga vegetal e no extrato seco de E. giganteum de alto teor de minerais, corrobora seu uso como remineralizante. Os resultados obtidos neste trabalho representam as primeiras contribuições para o estabelecimento de parâmetros e métodos para a caracterização e o controle de qualidade da droga vegetal de E. giganteum. A viabilidade de produção e a caracterização do extrato seco obtido contribuem para o desenvolvimento de novos produtos farmacêuticos e a avaliação de outras atividades biológicas.
Aerial stems of Equisetum giganteum L. (Equisetaceae, traditional name: ‘‘horsetail’’), a native plant from South America, are used in folk medicine for treating kidney and hepatic illness, due to their diuretic, hemosthatic, adstringent, remineralizant and weight loss properties. However, few scientific studies have been performed regarding this species. Concerning the biological properties, diuretic and antimicrobial activities, as well as no oral acute toxicity in mice have been reported. Considering the large availability of the E. giganteum in the Brazilian market and its therapeutic potential, the definition of the quality control parameters for the raw material, as well as the development of standardized products with well-established biological activities becomes necessary. Thus, the aim of this work was to establish identification methods and to evaluate quality control parameters for the E. giganteum raw material in order to compare this species with others of the genus, as well as to develop and to characterize a spray-dried product from an aqueous E. giganteum extractive solution. Dried aerial stems of E. giganteum and other species available were employed in the comparative analysis by TLC, HPLC and UV/VIS total flavonoid content. The ash content was determined. Total phenolic and flavonoid contents were determined by UV/VIS spectrophotometric method. The TLC analysis was carried out on silica gel plates; mobile phase ethyl acetate:formic acid:glacial acetic acid:water (100:11:11:26); and detection with Natural Product reagent / UV at 365 nm. HPLC analysis of methanol extracts was performed with a C18 column and a diode-array detector. The plant raw material was also submitted to acid hydrolysis which was optimized using Central Composite Rotational Design and Response Surface Analysis for investigate the effects of HCl concentration and hydrolysis time. The corresponding flavonoid aglycones were extracted and analyzed by a previously validated HPLC method. Total flavonoid content was measured also by aluminium chloride colorimetric assay at 425 nm. In attempt to characterize phenolic compounds in E. giganteum, HPLC-DAD and HPLC-MS/MS analysis were performed. An aqueous extractive solution (AES) was prepared by decoction of E. giganteum grounded stems using water. The resulting AES was spray-dried using a Niro Production Minor equipped with rotary atomizer (GEA, Copenhagen, Denmark). The spray-dried extract was then characterized. The content of total ash and acidinsoluble ash (at 600 °C) in E. giganteum stems were 20.07 ± 0.21% and 13.75 ± 0.39% (mean ± S.D.), respectively. The total phenolic content was 7.27 ± 0.05 mg expressed as gallic acid equivalent per gram (GAE/g), and the total flavonoid content was 0.420 ± 0.014 g% (w/w). In the TLC of E. giganteum was verified the presence of spots characteristic of polyphenols. The HPLC fingerprint revealed the existence of some constituents with UV spectra characteristics of cinnamic acid and kaempferol derivatives. The differentiation between E. giganteum and E. arvense, and in a minor extension for E. hyemale and E. bogotense, was possible by the chromatographic profile in TLC and HPLC analysis. The possible presence of thiamine was characterized by TLC in these samples. In the optimum condition found for hydrolysis of E. giganteum raw material, quercetin and kaempferol aglicones were found. The comparative analysis of flavonoids aglycones using HPLC and total flavonoids spectrophotometric methods revealed similarities between E. giganteum, E. hyemale and E. bogotense, but not for E. arvense, which showed a distinct profile of aglycones. The HPLC-MS/MS analysis of E. giganteum hydroethanol extractive solution allowed to characterize some flavonoids heterosides, mainly quercetin and kaempferol derivatives, and other rare compounds. The spray-dried extract (SDE) of E. giganteum was obtained with a high process yield (85.6%) and characterized as a very fine powder with low density, poor flowability and high loss on drying, but low water activity. The high content of reducing sugars and minerals, represented by total ash, was also observed in the SDE and can explain some these characteristics. The high content of sugars and minerals in the SDE also corroborate the traditional use of the plant as remineralizant. The results obtained in this study represent one of the first contributions to the establishment of parameters and methods for the characterization and quality control of raw material of E. giganteum. The feasibility of production and subsequent characterization of dried extract obtained contributes to the development of new pharmaceuticals products and to the evaluation of new biological activities.

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Argyropoulos, Dimitrios [Verfasser]. "Modeling sorption behavior and process kinetics of lemon balm (Melissa officinalis L.) for optimization of drying with regard to quality and energy requirement / Dimitrios Argyropoulos." Aachen : Shaker, 2015. http://d-nb.info/1080761942/34.

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Schmitz-Schug, Iris [Verfasser], Ulrich M. [Akademischer Betreuer] Kulozik, Urs A. [Akademischer Betreuer] Peuker, and Petra [Akademischer Betreuer] Först. "Improving the nutritional quality of dairy powders – analyzing and modeling lysine loss during spray drying as influenced by drying kinetics, thermal stress, physical state and molecular mobility / Iris Schmitz-Schug. Gutachter: Ulrich M. Kulozik ; Urs A. Peuker ; Petra Först. Betreuer: Ulrich M. Kulozik." München : Universitätsbibliothek der TU München, 2014. http://d-nb.info/1064523226/34.

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Schmitz-Schug, Iris Verfasser], Ulrich M. [Akademischer Betreuer] Kulozik, Urs [Akademischer Betreuer] [Peuker, and Petra [Akademischer Betreuer] Först. "Improving the nutritional quality of dairy powders – analyzing and modeling lysine loss during spray drying as influenced by drying kinetics, thermal stress, physical state and molecular mobility / Iris Schmitz-Schug. Gutachter: Ulrich M. Kulozik ; Urs A. Peuker ; Petra Först. Betreuer: Ulrich M. Kulozik." München : Universitätsbibliothek der TU München, 2014. http://d-nb.info/1064523226/34.

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PINTO, Mariana Viana. "Obtenção e padronização de extrato seco de Mikania laevigata (guaco)." Universidade Federal de Goiás, 2011. http://repositorio.bc.ufg.br/tede/handle/tde/2105.

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Mikania laevigata Sch.Bip. ex Baker., popularly known as guaco, is a Brazilian medicinal plant belonging to Asteraceae family and widely used in medicine to treat coughs and respiratory disorders. It presents bronchodilator and antiulcer activities among others. Coumarins, terpenes and organic acids are the main chemical constituents of this specie. In the literature no studies were found concerning the production of standardized dried extracts from this plant specie, therefore the aim of this study was the obtaining and the characterization of standardized dry extract of this plant specie. M. laevigata leaves were collected, dried and crushed, resulting in the plant drug. The hydroalcoholic extract was obtained by percolation of the drug plant and the extraction liquid used was ethanol 80% (v/v). After drying experiments were carried out in order to investigate the influences of the extract feed rate and the drying adjuvant ratio in the characteristics of the dried extracts obtained.-coumaric acid and coumarin were used as chemical markers and were quantified by High Performance Liquid Chromatography (HPLC) in all stages of the process. An analytical method was validated following the criteria proposed by the Agência Nacional de Vigilância Sanitária (ANVISA), proving to be selective, linear, precise, accurate, sensitive and robust. In the characterization of plant drug the volatile content obtained was 9.00 ± 1.75%, the coumarin content was 0.72 ± 0.02% and the acid -coumaric content was 0.13 ± 0.005%. The average particle size was 444.823 m and swelling index was 3.2 in ethanol 80%, 4.27 in ethanol 50% and 10.13 in water. The hydroalcoholic extract presented a density of 0.9256 ± 0.0006 g / mL, total solids content of 5.18 ± 0.21%, pH 6.1 ± 0.00, alcohol content of 56% and viscosity of 5.57 mPas. The drying yields ranged from 11.35 to 54.11%, and all dried products presented volatiles content and water activity below 5% and 0.5, respectively. The selected condition to be used to obtain standardized dried extracts of M. laevigata was that performed with a smaller proportion of colloidal silicon dioxide (15%) and increased extract feed rate (6mL/min), in which levels were obtained coumarin and -coumaric acid content of 1.83 ± 0.004% and 0.80 ± 0.012%, respectively. The dry extract obtained in these conditions showed spherical particles and their antiulcer activity in the model of indomethacin induced ulcers was demonstrated, suggesting a gastroprotective effect of this extract. Comparison of powder, hydroalcoholic and dry extract chromatographic (TLC and HPLC) show that the hydroalcoholic extraction was suitable for the extraction of coumarin and -coumaric acid and the drying process did not cause changes in the chemical profile of the extract in relation to these substances. Thus, the production of dried extracts by spray drying from the leaves of M. laevigata can be an interesting and promising alternative for obtaining such an intermediate product.
Mikania laevigata Sch.Bip. ex Baker., conhecida popularmente como guaco, é uma planta medicinal brasileira, pertencente à família Asteraceae, muito utilizada em medicamentos para tratar a tosse e distúrbios respiratórios. Apresenta atividades broncodilatadora, antiulcerogênica entre outras. Cumarinas, terpenos e ácidos orgânicos são os principais constituintes químicos desta espécie. Na literatura pesquisada não foram encontrados trabalhos abordando a produção de extratos secos padronizados de guaco, por isso o objetivo deste trabalho foi a obtenção e a caracterização do extrato seco padronizado desta espécie vegetal. As folhas de guaco foram coletadas, secas em estufa e trituradas, obtendo-se a droga vegetal. O extrato hidroalcoólico foi obtido através da percolação da droga vegetal utilizando como líquido extrator etanol 80%(v/v). Em seguida foram realizados diversos experimentos de secagem por spray drying com o intuito de investigar as influências da vazão de alimentação do extrato e da proporção de diferentes adjuvantes de secagem nas características dos extratos secos obtidos. A cumarina e o ácido -cumárico foram utilizados como marcadores químicos e foram quantificados por Cromatografia Líquida de Alta Eficiência (CLAE) em todas as etapas do processo. Foi validado um método analítico seguindo os critérios propostos pela Agência Nacional de Vigilância Sanitária (ANVISA), o qual foi seletivo, linear, preciso, exato, sensível e robusto. Na caracterização da droga vegetal o teor de voláteis obtido foi de 9,00 ± 1,75%, o teor de cumarina foi de 0,72 ± 0,02% e o teor de ácido -cumárico foi de 0,13 ± 0,005%. O tamanho médio de partículas foi de 444,823 μm e o índice de intumescência foi de 3,2 em etanol 80%, 4,27 em etanol 50% e 10,13 em água. O extrato hidroalcoólico apresentou densidade 0,9256 ± 0,0006 g/mL, teor de sólidos totais de 5,18 ± 0,21%, pH 6,1 ± 0,00, teor alcoólico de 56% e viscosidade de 5,57 mPas. Os rendimentos de secagem variaram de 11,35 a 54,11%, sendo que em todos os produtos secos, foram observados teores de voláteis e atividade de água abaixo de 5% e 0,5, respectivamente. A condição selecionada para ser empregada na obtenção de extratos secos padronizados de guaco foi aquela realizada com menor proporção de dióxido de silício coloidal (15%), maior vazão de alimentação do extrato (6mL/min), na qual obteve-se teores de cumarina e ácido cumárico de 1,83 ± 0,004 e 0,80 ± 0,012, respectivamente. O extrato seco obtido nestas condições apresentou partículas esféricas e a sua atividade antiulcerogênica no modelo de úlceras induzidas por indometacina foi demonstrada, sugerindo-se um efeito gastroprotetor. O perfil cromatográfico (CCD e CLAE) do pó, do extrato hidroalcoólico e do extrato seco demonstrou que a extração hidroalcoólica foi adequada para a extração de cumarina e ácido-cumárico e o processo de secagem não ocasionou alterações no perfil químico do extrato em relação a estas substâncias. Dessa forma, a produção de extratos secos por spray drying a partir das folhas de M. laevigata pode ser uma alternativa interessante e promissora para a obtenção desse produto intermediário.

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Clua, Palau Glòria. "Application of quality by design and near infrared spectroscopy in manufacturing and control of freeze-dried drug products." Doctoral thesis, Universitat Autònoma de Barcelona, 2018. http://hdl.handle.net/10803/663954.

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Esta tesis describe la aplicación de la aproximación de Calidad por Diseño para el desarrollo y cualificación del proceso de liofilización de dos productos farmacéuticos, denominados IFDA e IFDB, desarrollados en la empresa Laboratorios Reig Jofre. IDFA está formado por un único principio activo, y se presenta en dos dosificaciones, mientras que IDFB es más complejo ya que, además del principio activo, contiene un excipiente. El proceso de liofilización se utiliza para transformar disoluciones de principios activos en productos sólidos más estables. Es un proceso lento y costoso, por lo tanto, su optimización es una prioridad en la industria farmacéutica. La liofilización se divide en tres etapas: congelación, secado primario o sublimación, y secado secundario o desorción. El secado primario es generalmente la etapa más larga y está relacionada con un mayor riesgo para la calidad del producto. Por lo tanto, la mayor parte de los esfuerzos se centraron en su optimización. En primer lugar, se definió la huella dactilar térmica de cada formulación, utilizando un conjunto de técnicas analíticas, como calorimetría de barrido diferencial, microscopía de liofilización o difracción de rayos X. A continuación, se estudió la influencia de la temperatura de la bandeja y la presión de la cámara sobre los atributos de calidad del producto y la eficiencia del proceso mediante un diseño experimental tipo Doehlert, estableciendo finalmente el espacio de diseño del secado primario a escala laboratorio. Las condiciones operativas del proceso industrial se seleccionaron centrándose en la reducción del tiempo de proceso a la vez que se preservaba la calidad del producto. Posteriormente, el proceso se transfirió y cualificó a escala industrial, y se confirmó que todos los lotes cumplían con las especificaciones de calidad del producto después de 12 meses de estabilidad, siguiendo las recomendaciones de la guía ICH Q1A(R2). Durante la cualificación del proceso de liofilización, se requirió un muestreo extensivo para garantizar la homogeneidad del secado. Este gran número de muestras no puede analizarse de manera efectiva mediante el método convencional de Karl Fischer. En consecuencia, se desarrolló y validó un método de espectroscopia de infrarrojo cercano (NIR del inglés near infrared) para la determinación del contenido de humedad residual en las dos dosis del producto liofilizado IFDA de manera no destructiva y rápida. La viabilidad del uso de la espectroscopia NIR para la predicción de la humedad residual en viales liofilizados se evaluó utilizando herramientas de análisis de riesgos y estudios de mitigación de riesgos. Se creó un único modelo útil para las dos dosis del producto IFDA, con el objetivo final de obtener el modelo más simple y robusto con una capacidad predictiva aceptable. Durante la validación del método, se prestó especial atención a la estimación del límite de detección y se propuso un enfoque de cálculo útil para el caso estudiado. Finalmente, el modelo NIR se aplicó para realizar un mapeo de humedad de dos liofilizadores industriales y para evaluar su posible aplicación para analizar muestras sometidas a diferentes condiciones de almacenamiento.
This thesis describes the application of Quality by Design for the development and qualification of the freeze-drying process of two drug products, named IFDA and IFDB, developed in Laboratorios Reig Jofre. IDFA is composed by an Active Principle Ingredient (API), and it is presented in two different strengths, while IDFB is more complex since, in addition to the API, it contains an excipient. The freeze-drying process is used to transform solutions of active ingredients in more stable solid products. It is a time-consuming and expensive process; hence a successful development and optimization is a priority in the pharmaceutical industry. This process is divided in three stages: freezing, primary drying or sublimation and secondary drying or desorption. The freeze-drying process optimization was focused on the primary drying, since it is usually the longest stage and it is generally related with the highest impact to product quality. First, characterization studies of both formulations were performed to define their thermal fingerprint using a variety of analytical techniques, such as differential scanning calorimetry, freeze-drying microscopy or X-ray powder diffraction. Then, the influence of primary drying shelf temperature and chamber pressure on product quality attributes and process efficiency was studied through a Doehlert design, and the design space was established at lab-scale. The process operational conditions for production manufacturing were selected focusing on process time reduction while preserving the quality of the product. Afterwards, the process was scale-up and qualified at industrial scale, and it was confirmed that all batches complied with product quality specifications after 12 month of ICH stability studies. During freeze-drying qualification, extensive sampling was needed to guarantee the homogeneity of the drying process. This large number of samples cannot be effectively analysed by the conventional Karl Fischer method. Consequently, a non-destructive and fast near infrared spectroscopy (NIRS) method was developed and validated for residual moisture content determination in the two strengths of IFDA drug product. The feasibility of using near infrared spectroscopy for the intended purpose was assessed using risk analysis tools and risk mitigation studies. A single model useful for two strengths of the injectable freeze-dried product was built up, with the final aim of obtaining the most simple and robust model with an acceptable predictive ability. During method validation, special attention was placed in the estimation of the limit of detection and a calculation approach was proposed. Finally, this NIRS model was applied to perform a moisture mapping of two industrial freeze-dryers, and to evaluate the potential application of the NIRS method to analyse samples subjected to different storage conditions.

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OLIVEIRA, Patrícya Caixeta de. "Obtenção e Caracterização do Extrato Seco Padronizado dos Frutos da Sucupira Pterodon emarginatus Vogel, Fabaceae." Universidade Federal de Goiás, 2010. http://repositorio.bc.ufg.br/tede/handle/tde/2095.

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The Pterodon emarginatus Vogel, known as sucupira branca (Fabaceae) has been shown to possess larvicidal activity against (Aedes aegypti), antiparasitic effect (Leishmania amazonensis), fungicide, bactericide, antioxidant, antiinflammatory, antinociceptive, and antiproliferative activity among several different human cancer cell lines that may be related to presence of diterpenes, in particular, vouacapanes derivatives. This work aimed to define and characterize the powder, the crude and standardized dry extract of the fruit of sucupira . After crushing the fruits, showed 1.2% volatile. The chromatographic (TLC) indicated the presence of chemical markers vouacapanes (6α,7β-dihydroxyvouacapan-17β-oic acid - Rf = 0.16; 6α,7β-dihydroxyvouacapan-17β-oate methyl ester - Rf = 0.44; 6α-hydroxyvouacapan-7β-17β-lactone - Rf = 0.71) and lupeol (Rf = 0.78). In vibration bands in the infrared region coinciding with the five main bands of vouacapanes (-OH, C-H , C=O, C=C, C-O). The concentration of total terpenes of 9.3%. Then to obtain the crude extract was held percolation in 95% ethanol PA. The crude extract showed pH 5.1, relative density of 0.87, viscosity of 25.43 mPas, solid 15.2%, total terpenes of 17.1% and the same chromatographic profile and in the infrared spectrum obtained for the powder plant. Another method used for investigation of terpenes was the gas chromatography / mass spectrometry in the hexane extract. We identified the presence of vouacapanes and the lupeol. The drying process of the crude extract was used nebulization (spray drying) using different adjuvants drying, flow of 0.19 L / h, air flow 35 L / min, inlet temperature 110°C, outlet temperature 97°C, double fluid nozzle spray type 1.2 mm. The best results were obtained with the colloidal silicon dioxide (Aerosil®) to 20%, giving an appearance of fine powder. Thermal analysis performed for the marker 6α,7β-dihydroxyvouacapan-17β-oate methyl ester showed that the drying parameters were safe by preventing the thermal degradation of diterpenes. The efficiency of the drying process was 16.2%, degradation of 10.9% and the concentration of terpenes total in dry extract was 13.9%. The chromatographic profile was maintained and the volatile content was 3.5%. The photomicrographs showed irregular and spherical particles, rough surface. The analytical method by spectrophotometry in the visible region for the quantification of total terpenes in the dust, crude extract and dry extract was validated presenting selective, linear, precise, accurate and robust. In the test of antinociceptive activity (capsaicin), the pre-treatment with dry extract of sucupira (SDE 1000 mg / kg + 20% DMSO) reduced the time reactivity in 50.9% compared to the vehicle. The results may suggest that the technological processes employed to transform the fruits of sucupira in standardized dry extract was adequate to maintain quality chemistry and antinociceptive activity described for the fruits. This work represents the first description of the taking of standardized dry extract and identification of lupeol in fruits of sucupira .
A Pterodon emarginatus Vogel, conhecida popularmente como Sucupira Branca, pertence à família Fabaceae. Estudos científicos comprovaram atividades larvicida (Aedes aegypti), antiparasitária (Leishmania amazonensis), fungicida, bactericida, antioxidante, antiinflamatória, antinociceptiva e anti-tumoral nos frutos dessa espécie, que podem estar relacionadas com a presença de diterpenos, de modo particular, os derivados vouacapânicos. Esse trabalho teve como objetivo obter e caracterizar o pó, o extrato bruto e extrato seco padronizado dos frutos da sucupira. O material botânico foi moído, obtendo-se um pó grosso, apresentando 1,2% de voláteis. O perfil cromatográfico (CCD) indicou a presença dos marcadores vouacapânicos (ácido 6α, 7β, di-hidroxivouacapan-17-β-óico - Rf = 0,16; 6α, 7β, di-hidroxivouacapan-17-β-oato de metila Rf = 0,44; 6α, hidroxivouacapan-7β, 17β-lactona Rf = 0,71) e lupeol (Rf = 0,78). Foram observadas bandas de vibração na região do infravermelho coincidentes com as cinco bandas principais dos vouacapanos (-OH, C-H , C=O, C=C, C-O). O teor de terpenos totais foi de 9,3%. Procedeu-se a obtenção do extrato bruto por percolação em etanol a 95% P.A. Este apresentou pH 5,1, densidade relativa de 0,87, viscosidade de 25,43 mPas, teor de sólidos de 15,2%, teor de terpenos totais de 17,1%, o mesmo perfil cromatográfico e espectro na região do infravermelho obtido para o pó do fruto. Outro método utilizado para investigação de terpenos foi a cromatografia gasosa acoplada à espectrometria de massas realizada no extrato hexânico. Identificou-se a presença de voaucapanos e do lupeol. Em seguida, realizou-se o processo de secagem do extrato bruto por nebulização (spray drying), utilizando diferentes adjuvantes de secagem, fluxo de 0,19 L/h, vazão do ar 35 L/min, temperatura de entrada 110°C, temperatura de saída 97°C, bico aspersor tipo duplo fluido 1,2 mm. Os melhores resultados foram obtidos com o dióxido de silício coloidal (Aerosil®) a 20%, proporcionando um aspecto de pó fino. A análise térmica realizada para o marcador 6, 7-dihidroxivouacapan-17-oato de metila demonstrou que os parâmetros de secagem foram seguros prevenindo a degradação térmica dos diterpenos. O rendimento do processo de secagem foi de 16,2%, a porcentagem de degradação de 10,9% e o teor de terpenos totais no extrato seco foi de 13,9%. O perfil cromatográfico foi mantido e o teor de voláteis foi de 3,5%. As fotomicrografias obtidas para o extrato seco mostraram partículas de formato irregular e esférico e superfície rugosa. O método analítico desenvolvido por espectrofotometria na região do visível para a quantificação dos terpenos totais no pó, extrato bruto e extrato seco foi validado apresentando-se seletivo, linear, preciso, exato e robusto. No teste de atividade antinociceptiva (capsaicina), o pré-tratamento com extrato seco de sucupira (ESS 1000 mg/kg + DMSO 20%) reduziu o tempo de reatividade em 50,9% em relação ao veículo. Os resultados obtidos permitem sugerir que o processamento tecnológico empregado para a transformação dos frutos da sucupira em extrato seco padronizado foi adequado, mantendo a qualidade química e a atividade antinociceptiva descritas. Esse trabalho representa a primeira descrição da obtenção do extrato seco padronizado e da identificação do lupeol nos frutos da sucupira.

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Stangerlin, Diego Martins. "AVALIAÇÃO DO USO DE ESTUFA SOLAR PARA SECAGEM DE MADEIRA SERRADA DE EUCALIPTO." Universidade Federal de Santa Maria, 2009. http://repositorio.ufsm.br/handle/1/8640.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
This study aimed at evaluating the use of solar kiln for the drying of woods of Eucalyptus tereticornis, Eucalyptus saligna and Corymbia citriodora, as well as comparing the methodology to the air drying. In order to do so, it was built a solar kiln composed basically of wood structures, roofing with a double layer of PVC plastic, sunlight internal collector system and hot air circulation system. The efficiency of the solar kiln was compared to the air drying in the following aspects: time and drying tax, variation of the environmental conditions and wood quality resulting from the drying. The three eucalyptus species used in this experiment were obtained from homogeneous stands, and the cutting of logs into planks was tangential. In the same period of drying, each species was submitted to the two drying methods, being used a load with 60 boards in each method. Results indicated that the solar kiln had been more efficient as for time and drying tax. The time of drying in solar kiln was around 2 to 5 times faster than the air drying. Although the experiments were carried out in the winter, in low insolation and solar radiation, the drying in solar kiln presented satisfactory drying taxes, similar to those ones observed in more sophisticated solar kiln all over the world. Even when the conditions were not favorable to the air drying, the solar kiln presented higher temperatures and smaller indexes of moisture content and of equilibrium. The dried wood, in solar kiln and air drying, presented good quality, and no incidences like cup or collapse were verified. Furthermore, the correct piling up and drying process provided minimization of defects like bow. Despite the major occurrences of pieces with crook in solar kiln drying, the differences among the crook arrows, in the two drying methods, were insignificant. The incidence of end checking occurred from the drying in solar kiln was smaller in relation to the air drying only for woods of Eucalyptus tereticornis. On the other hand, the incidence of surface checks followed from the drying in solar kiln was inferior in comparison to the air drying process for the wood of Corymbia citriodora and Eucalyptus saligna.
O objetivo desse estudo foi avaliar o uso da estufa solar para secagem das madeiras de Eucalyptus tereticornis, Eucalyptus saligna e Corymbia citriodora, bem como comparar a metodologia com a secagem ao ar livre. Para tanto, foi desenvolvido um secador solar composto basicamente de estruturas de madeira, cobertura com dupla camada de plástico PVC, sistema coletor interno de luz solar e sistema de circulação do ar aquecido. A avaliação da eficiência do secador solar foi comparada à secagem ao ar livre nos seguintes aspectos: tempo e taxa de secagem, variação das condições ambientais e qualidade da madeira resultante da secagem. As três espécies de eucalipto utilizadas nesse experimento foram obtidas em povoamentos homogêneos, sendo o desdobro realizado por meio de cortes tangenciais. Cada espécie foi submetida, no mesmo período, aos dois métodos de secagem, utilizando-se uma carga com 60 tábuas em cada método. Os resultados obtidos indicaram que a estufa solar foi mais eficiente quanto ao tempo e à taxa de secagem. Os tempos de secagem em estufa solar foram em torno de 2 a 5 vezes menores que a secagem ao ar livre. Apesar dos ensaios terem sido realizados durante o inverno, com baixa insolação e radiação solar, a secagem em estufa solar apresentou taxas de secagem satisfatórias, semelhantes às observadas em secadores solares mais sofisticados espalhados pelo mundo. Mesmo quando as condições não eram propícias à secagem ao ar livre, a estufa solar apresentou maiores temperaturas e menores índices de umidade relativa do ar e de equilíbrio. A madeira seca, tanto na estufa solar quanto ao ar livre, apresentou boa qualidade, não sendo verificada a incidência de defeitos como encanoamento e colapso. Além disso, o adequado processo de empilhamento e secagem proporcionou minimização dos defeitos do tipo encurvamento. Apesar da maior ocorrência de peças arqueadas na secagem em estufa solar, a diferença entre as flechas de arqueamento, nos dois métodos de secagem, foi mínima. A incidência de rachaduras de topo resultantes da secagem em estufa solar foi inferior em relação ao ar livre apenas para a madeira de Eucalyptus tereticornis. Já a incidência de rachaduras superficiais resultantes da secagem em estufa solar foi inferior em comparação ao processo ao ar livre para as madeiras de Corymbia citriodora e Eucalyptus saligna.

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Oliva, Ana Cristina Ensinas de [UNESP]. "Qualidade de sementes de crambe submetidas a métodos de secagem e períodos de armazenamento." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/90483.

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O crambe (Crambe abyssinica Hochst) é uma planta da família Brassicaceae cujas sementes possuem elevado teor de óleo, sendo destinado no Brasil, principalmente, para a produção de biodiesel. É uma cultura que apresenta baixo custo de produção, seu cultivo é totalmente mecanizado com semedura no inverno e favorece a rotação com outras culturas de verão. No Brasil, a produção e a comercialização de sementes de crambe iniciaram-se há poucos anos, por isso estudos na área de tecnologia de produção são essenciais para obtenção de sementes de boa qualidade. Dentre os fatores que afetam a qualidade das sementes está o processo de secagem. A diminuição do teor de água das sementes em níveis adequados permite preservar as sementes por um período prolongado, possibilitando menor perda de vigor e germinação ao longo do armazenamento. O objetivo deste estudo foi avaliar o efeito de diferentes métodos de secagem sobre a qualidade de sementes de crambe no decorrer do armazenamento. O campo de produção de sementes de crambe foi instalado na Fazenda Experimental Lageado e os tratamentos experimentais foram conduzidos no Laboratório de Processamento de Produtos Agrícolas, pertencente ao Departamento de Engenharia Rural, e na Fazenda Experimental Lageado. As avaliações de qualidade foram realizadas no Laboratório de Análise de Sementes pertencente ao Departamento de Produção Vegetal – Setor Agricultura...
Crambe (Crambe abyssinica Hochst) is a member of the Brassicaceae family. Its seeds have high oil contents and its growth in Brazil aims to produce bio diesel. It is a low cost production and its cultivation is totally mechanized. It is also sowed at winter time, which favors crop rotation with other summer crops. In Brazil, Crambe seeds production and commercialization began a few years ago. The research in technology production is essential to obtain high quality seeds. Among the factors that affect seed quality there is the drying process. Seed water content decreased to an appropriate level allowing for a prolonged preservation time and enabling less vigor and germination loss during storage. The aim of this study was to evaluate the effect of different drying methods on Crambe seeds quality during storage. The seeds were produced in Fazenda Lageado, Faculdade de Ciências Agronômicas, UNESP, Botucatu / SP. Experimental treatments were conducted at Laboratório de Processamento de Produtos Agrícolas, Departamento de Engenharia Rural, and Fazenda Experimental Lageado. Evaluations on seed quality were conducted at Laboratório de Análise de Sementes, Departamento de Produção Vegetal – Setor Agricultura. Seeds were submitted to the following drying methods: a) seed drying in the shade with natural ventilation; b) artificial drying method using heated air; c) artificial drying method using unheated air; d) drying on ceramic patio; e) drying on the mother plant. Seeds were stored in laboratory conditions with bimonthly monitoring of their quality during a 8 month period. The following testes were performed: seed moisture content, standard germination test, first count of germination test, seedling emergence,emergence speed index and electrical conductivity. The accelerated ageing and seedling growth tests were performed on the 8th month of storage. The data obtained in each storage... (Complete abstract click electronic access below)

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Nicoleti, JOel Fernando. "Secagem de caqui em condições controladas : efeito sobre a qualidade do produto e consumo energetico." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255778.

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Orientadores: Vivaldo Silveira Junior, Vania Regina Nicoletti Telis
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Doutorado
Engenharia de Alimentos
Doutor em Engenharia de Alimentos

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Paula, Luciana Teixeira de [UNESP]. "Estudo da secagem do café cereja despolpado em diferentes tempos de fermentação." Universidade Estadual Paulista (UNESP), 2005. http://hdl.handle.net/11449/90767.

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A cultura do café representou grande destaque no setor econômico essa posição ainda é muito expressiva por ser o maior produtor exportador. Atualmente o café produzido no Brasil vem sofrendo perdas em virtude da falta de qualidade dos grãos, prejudicando a bebida final. A qualidade dos grãos está diretamente ligada a diversos fatores especialmente ao tipo de colheita, estágio de maturação e tempo de fermentação anterior à secagem. Este trabalho teve como objetivo avaliar o efeito do tempo de fermentação na secagem e nas propriedades físicas do grão de café cereja despolpado. Os tempos de fermentação foram de 0, 24 e 48 horas. Utilizou-se um secador de leito fixo, com velocidade do ar de 1 e 2 m/s a temperaturas de 40, 50 e 60°C, por um período de 24 horas. Durante o processo de secagem acompanhou-se a variação da densidade real e aparente e o encolhimento do grão. Avaliou-se como parâmetro de qualidade a coloração dos grãos. O modelo que melhor representou os dados experimentais foi de Page. A velocidade de secagem foi afetada pela temperatura e a velocidade do ar teve efeito somente a 40°C. Quanto menor o tempo de fermentação maior é a velocidade de secagem, sendo que o teor final de umidade não foi afetado. As propriedades físicas do café despolpado variam com a secagem segundo uma relação linear. A cor dos grãos é afetada pela temperatura de secagem, enquanto que a velocidade do ar e o tempo de fermentação não tiveram efeito visível.
The culture of coffee representes great prominence in the economic sector of our country that still occupies prominence for being the bigges exporting producer . Currently the coffee produced in Brazil has suffered losses in virtue from the quality lack of the grain, harming the finish drink. The quality of the grains is directly releted to several factors especially to the type of harvest, period of training of maturation and time of previous fermentation to the drying. It had with the objective to evaluate the effect of the time of fermentation in the drying and in the physical properties of the grain of pulped coffee cherry the fermentation times had been of 0, 24 and 48 hours. A drier of fixed stream bed was used, with 2 air speed of 1 and m/s the temperatures of 40, 50 and 600 C, for a period 24-hour. During the drying process it was accompanied by variation of the real and apparent density and the shrinking of the grain. The coloration of the grains was evaluated as quality parameter. The model that better represented the experimental data was of Page. The drying rate was affected by the temperature and the air speed only had effect 400 C. How much lesser the time of bigger fermentation is the drying speed, being the final text of humidity was not affected. Isicas properties f of the pulped coffee vary with the drying as a linear relation. A color of the grains is affected by the temperature of drying. While, that the air speed and the time of fermentation visible did not have effect.

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