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1
Miller, John Joseph. "John Stuart Mill on quality and competence." Full text, Acrobat Reader required, 2001. http://viva.lib.virginia.edu/etd/diss/ArtsSci/Philosophy/2001/Miller/Mill2.PDF.
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Mejeoumov, Gleb Gennadievich. "Improved cement quality and grinding efficiency by means of closed mill circuit modeling." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-2478.
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Hanna, Taryn. "Evaluation of Watershed Land Use and Water Quality in Mill Creek, Youngstown, Ohio." Youngstown State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1504173202262152.
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Ampomah, Shadrack AMPOMAH. "The Influence of Land Use on Sediment Quality in the Mill Creek Watershed." Youngstown State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1525362794556873.
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Mohammed, Afrah Eltayeb. "Organically-grown tomato (Lycopersicon esculentum Mill.) plant infection by Phytophthora infestans and fruit quality." Göttingen Optimus, 2009. http://d-nb.info/100035699X/04.
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Avşar, Hakan Doymaz Fuat. "Control, Optimization And Monitoring Of Portland Cement (Pc 42.5) Quality At The Ball Mill/." [s.l.]: [s.n.], 2006. http://library.iyte.edu.tr/tezler/master/kimyamuh/T000365.pdf.
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Baasandorj, Tsogtbayar. "Hard Red Spring Wheat Quality Evaluation with Various Roller Mill Types and Breadmaking Methods." Diss., North Dakota State University, 2016. http://hdl.handle.net/10365/25923.
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Roller mill type and breadmaking methods might be a source of variation in the evaluation of the end-use quality of Hard Red Spring (HRS) wheat. In this study, various roller mill types and baking methods have been used to investigate whether they affect end-use quality evaluation of HRS wheat cultivars. In addition, a quality scoring system has been developed to determine if ranking of the HRS wheat cultivars would change when different roller mills and breadmaking methods were used. Both the roller mill type and breadmaking method had an effect on the end-use quality of HRS wheat cultivars. When using different roller mills for quality evaluation, HRS wheat samples of MN Bolles and ND Glenn from Gulf/Great Lakes (G/GL) region and ND Glenn from Casselton location had overall quality scores of 6.5 or above when averaged across mill types. When using various baking methods and conditions for quality evaluation, ND 817, MN Bolles, ND Glenn cultivars from Pacific Northwest region, and MN Bolles and ND Glenn from G/GL region received overall baking quality scores of 6.5 or above hence these cultivars were considered to have ?excellent? baking quality characteristics under different baking conditions. The results in the current research study indicate that although there are differences in the mill type and breadmaking methods on the end-use quality evaluation, the ranking of HRS wheat flours is not affected by the mill type or baking methods and conditions. In other words, cultivars considered to have ?fair? quality tend to have low end-use quality, while ?excellent? cultivars will have superior end-use quality regardless of the roller mills and/or baking method and processing conditions used. The proposed overall wheat scoring system could assist farmers and breeders in selection of wheat cultivars considering the wheat end-use quality. Development of a comprehensive scoring system will also enable a more detailed scoring system for screening new lines for suitable end-use.North Dakota Wheat Commission
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Sayajon, Glynda Fe Garela. "Application of Handheld Infrared Spectrometer for Screening Quality Traits in Tomato (Lycopersicon esculentum Mill.) Cultivars." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1306941612.
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Serrano, Eleazar Hoose. "Practical Force Control on the Last Stand of a Hot Strip Mill." University of Toledo / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=toledo15133403699151.
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Mutabaruka, Celestin. "Investigation of factors affecting sweet chestnut (Castanea sativa Mill.) timber quality in relation to shake defect." Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.427822.
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Koirala, Manasa. "Impact of Land Use on Water Quality of Mill Creek Watershed in the Mahoning Valley, Ohio." Youngstown State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1560257033109932.
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Langenhoven, Petrus. "Yield and quality response of hydroponically grown tomatoes (Lycopersicon esculentum Mill.) to nitrogen source and growth medium." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/50232.
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Dissertation (PhD)--Stellenbosch University, 2004.ENGLISH ABSTRACT: Pine sawdust-shavings (Pinus spp.) is at present a very popular soilless substrate in South African greenhouses. Growers use fresh pine sawdust-shavings as a substrate, which is biologically highly unstable. The greenhouse industry is looking at alternative organic substrates such as coco peat, which already went through a decomposition process and is more stable. A biological inactive substrate such as sand was included to compare microorganism activity with organic substrates. The main objective of this study was to compare the growth, yield and quality of hydroponically grown tomatoes in response to different growth mediums in combination with nitrogen source, irrigation frequency, period of substrate use and liming. In general the drainage water pH declined with an increase in NlLt+-N in the nutrient solution. Low pH values in the drainage water, especially when coco peat was used, had a detrimental effect on marketable yield. The drainage water pH of pine sawdustshavings increased during the growing season when 100 % N03--N was used. Due to the higher cation exchange capacity of coco peat, the drainage water electrical conductivity tends to increase more rapidly than with pine sawdust-shavings, during conditions with high temperatures and when insufficient irrigation volumes per irrigation cycle is applied. As expected the drainage water N03--N content decreased as the NlLt+-N content increased in the nutrient solution. Pine sawdust-shavings recorded a much lower N03--N and NlLt+-N content than sand and coco peat and thus supports the hypothesis that microbiological activity is higher in pine sawdustshavings, especially in the second season of substrate use. Coco peat produced the highest number of marketable fruit and yield per plant, followed by pine sawdustshavings and sand in the first season of substrate use. The number of marketable fruit and yield decreased with an increase in NlLt+-N content in the nutrient solution during production in warmer, summer conditions. Contrary to these fmdings, production in cooler, winter conditions recorded high yields when only N03--N or 80% N03--N : 20% NRt +-N was applied. The unmarketable yield increased with an increase in NlLt+-N in the nutrient solution. Visual evaluations showed that blossom-end rot (BER) was the main contributor to unmarketable yield. Increasing levels ofN03--N as nitrogen source in the nutrient solution, reduced weight loss and increased the loss of fruit firmness of tomatoes during storage. Increasing levels of N03 --N also increased fruit pH and reduced total titratable acidity. Coco peat produced fruit with a higher pH than pine sawdust-shavings. An increase in irrigation frequency affected fruit firmness negatively when coco peat was used as substrate. Different irrigation and fertigation practices are needed for different growth mediums and management needs to be adapted according to the growing season (winter vs. summer).
AFRIKAANSE OPSOMMING: 'n Mengsel van dennesaagsels en -skaafsels (Pinus spp.) word tans deur Suid- Afrikaanse kweekbuisprodusente gebruik as grondlose groeimedium. Hierdie groeimedium word nie vooraf gekomposteer nie en is dus biologies onstabiel. Die kweekbuisindustrie ondersoek tans die gebruik van alternatiewe, gekomposteerde en stabiele organiese groeimediums soos kokosveen. 'n Biologies onaktiewe groeimedium soos sand is ook ingesluit om met organiese groeimediums te kan vergelyk. Die hoof doelwit van die studie was om plantontwikkeling, opbrengs en kwaliteit van hidroponies geproduseerde tamaties te evalueer in verskillende groeimediums en in kombinasie met stikstofbron-verhouding, periode van groeimedium gebruik, besproeiingsfrekwensie en bekalking. Oor die algemeen het die pH in die dreinaat gedurende die groeiseisoen toegeneem soos die NH/-N inhoud verhoog het in die voedingsoplossing. Lae pH waardes in die dreinaat, veral waar kokosveen gebruik was, het 'n nadelige effek op bemarkbare opbrengs gehad. Die pH in die dreinaat van dennesaagsels en -skaafsels het gedurende die groeiseisoen toegeneem met die gebruik van 100% NO)--N in die voedingsoplossing. Die elektriese geleiding in die dreinaat van kokosveen neem vinniger toe gedurende toestande waarin hoë temperature en onder besproeiing voorkom, as in dreinaat van dennesaagsels en -skaafsels. Die NO)--N inhoud in die dreinaat het soos verwag afgeneem soos die NRt+-N inhoud in die voedingsoplossing toegeneem het. 'n Baie laer NO)--N en NRt+-N inhoud is by dennesaagsels en -skaafsels aangeteken wat dus die hipotese ondersteun dat mikrobiologiese aktiwiteit, veral in die tweede seisoen van gebruik, hoër is in dennesaagsels en -skaafsels as in sand en kokosveen. Kokosveen het die hoogste aantal bemarkbare vrugte en massa per plant geproduseer, gevolg deur dennesaagsels en -skaafsels en sand. Die aantal bemarkbare vrugte en opbrengs het verlaag met 'n verhoging in NRt+-N in die voedingsoplossing gedurende warm, somer toestande. In teenstelling met vorige resultate is gevind dat 100% NO)-- N of 80% NO)--N : 20% NRt+-N hoë opbrengste gelewer het gedurende koeler, winter toestande. Die onbemarkbare opbrengs het verhoog met hoër NRt+-N vlakke. Visuele waarnemings het aangedui dat blom-end verrotting die grootste bydrae tot onbemarkbare opbrengs gelewer het. 'n Verhoging in NO)--N vlakke het massaverlies beperk en die verlies in fermheid verhoog gedurende opberging. Hoër NO)--N vlakke het ook die pH van vrugte verhoog en die totale titreerbare suur verlaag. Kokosveen het vrugte met 'n hoër pH as dennesaagsels en -skaafsels geproduseer. 'n Toename in besproeiingsfrekwensie het vrug fermheid negatief beïnvloed wanneer kokosveen as groeimedium gebruik was. Verskillende besproeiings- en voedingspraktyke word benodig vir verskillende groeimediums en bestuur van die groeimediums moet aangepas word by klimaatstoestande gedurende die spesifieke produksieseisoen.
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Msibi, Sifiso Thuthukani. "Nitrogen nutrition of tomato (Lycopersicon esculentum Mill.) transplants and the influence of electrical conductivity on crop growth, yield and quality." Diss., University of Pretoria, 2014. http://hdl.handle.net/2263/46057.
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Nitrogen is required by plants in large quantities and its deficiency is mostly related to reduction in crop production. A study was conducted to assess the importance of nitrogen in tomato (Lycopersicon esculentum Mill.) transplant production. Transplants were propagated at 0, 30, 60, 90, and 120 mg∙L-1 N applied as NH4NO3 while 30 mg∙L-1 P applied as NaH2PO4 and 30 mg∙L-1 K as KCl were used. Fergitation was done by floating cavity trays in nutrient solution until the medium reached field capacity. The experiment was arranged in a randomized complete block design (RCBD) with four replications. Sampling was initiated at 21 days after sowing and was done weekly until the transplants were ready for transplanting (when transplants could be pulled out of the cavity easily without breaking) at 42 days after sowing.
Nitrogen supply had a pronounce influence on the transplant root and shoot growth. Observations throughout the experiment indicated that increased nitrogen application favoured shoot growth which is an indication that most of the assimilates were partitioned to shoots rather than to roots. Nitrogen application of 120 mg∙L-1increased fresh shoot mass and subsequently enhanced dry shoot mass. As nitrogen was increased from 0 to 120 mg∙L-1, it further promoted relative growth rate, specific leaf area, leaf mass ratio, leaf area ratio, plant chlorophyll content, leaf tissue nitrogen and improved the pulling success. At 42 days after sowing, a quality transplant that was produced with 90 mg∙L-1 N, had a root to shoot ratio of 0.16, leaf mass ratio of 0.86, root mass ratio of 0.13, leaf area of 594 cm2, plant chlorophyll content of 33, leaf tissue nitrogen of 32 g∙kg-1, specific leaf area of 194 cm2∙mg-1, leaf area ratio of 167.7 cm2∙mg-1, relative growth ratio of 0.31 cm∙mg-1∙wk-1 and 100% pulling success. This transplant proved to be ideal for the production of tomato as compared to other treatment combinations that were employed.
Another glasshouse experiment was conducted to determine the influence of electrical conductivity (EC) and or nutrient solution composition on growth, yield and quality parameters in tomato. The pots were arranged in a randomized complete block design (RCBD). One plant per pot represented an experimental unit. Four EC treatments were used that consisted of 1.12, 2.24, 4.48 and 6.72 mS∙cm-1. Each treatment was replicated six times. Distilled water was used for irrigation water to maintain the required pH, which was 5.5 to 6.2 throughout the duration of the study, and cocopeat was used as substrate.
Salinity inhibited growth (shoot length) and yield (average fruit mass, fruit diameter and fruit circumference) at the highest concentration of 6.72 mS∙cm-1. However, it did not significantly affect number of trusses, number of fruits and stem diameter, rather tomato quality was improved in terms of total soluble solids. Although tomato fruits grown at 6.72 mS∙cm-1 were relatively smaller than fruits grown at 1.12, 2.24 and 4.48 mS∙cm-1 treatments respectively, they had higher acidity, increased soluble solids and higher sugar content which are all qualities required by the tomato processing industry. Increasing the concentration of the solution from 1.12 to 6.72 mS∙cm-1 increased the %Brix from 3.9 to 6.1% while titratable acidity was also increased from 3.3 to 5.7%, respectively. The incidents of blossom end rot were higher (6.3%) at concentration of 6.72 mS∙cm-1 as compared to 1.12 mS∙cm-1 concentration, which was 0.5%.Dissertation (MScAgric)--University of Pretoria, 2014.
tm2015
Plant Production and Soil Science
MScAgric
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Carver, Melissa. "Nutrient Concentrations and Effects on Mill Run from Residential, Urban, and Industrial Stormwater Contamination." Thesis, NSUWorks, 2019. https://nsuworks.nova.edu/occ_stuetd/505.
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Nutrients are introduced into the waters of the Commonwealth of Pennsylvania through various methods, mainly through point and non-point sources. Non-point sources would include agricultural means however, there are often other non-point sources that are often overlooked. Water runoff from stormwater is an important contributor to pollution entering various watersheds. Data was collected at 4 locations (the initial point of reference, residential, urban, and industrial) on Mill Run and 2 locations on Woodcock Creek, through surface water collection methods in dry and wet weather. Nitrate, Nitrite, Total Phosphorus, and Total Nitrogen were among the data collected. Total Phosphorus had an increasing trend in concentration as the study progressed. Nitrate, Nitrite and Total Nitrogen showed no increasing trends. Location 3 (Urban Zone) produced the largest increase in Total Phosphorus. Weather conditions played a role in higher Nitrate concentrations while warm water produced higher Nitrite concentrations
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Novela, Precious. "Delayed fruit harvest on yield, nutritional value and post-harvest quality of late maturing reed avocado (Persea Americana Mill)." Thesis, University of Limpopo, 2016. http://hdl.handle.net/10386/1711.
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Thesis (MSc .(Plant Production)) -- University of Limpopo, 2016Delayed fruit harvest (DFH) or on-tree-fruit storage is a strategy being considered to extend the harvest season of late maturing ‘Reed’ avocado. However, avocado fruit growth beyond physiological maturity is accompanied by alterations in chemical and physical properties. Thus, the study aimed to investigate the effects of delayed harvest on tree productivity, mineral nutrition and post-harvest quality of late maturing ‘Reed’ avocado and further to evaluate the fruit quality response to varying ripening temperature regimes. As treatments, fruit were harvested early, mid and late in the season, with one month apart from each harvest during 2013 and 2014 seasons. Yield and fruit size were recorded at harvest. During each harvest time, two sets of fruit samples were collected to determine the fruit nutritional content while the second set was cold stored at 5.5°C for 28 days. After storage, fruit were ripened at 16, 21 or 25°C and evaluated for post-harvest disorders, pathological diseases and fruit physico-chemical properties. Yield dropped from 42 to 12 kg/tree from early to late harvest during 2013, while treatments showed no effect during 2014. Furthermore, treatments had no effect on fruit size during both seasons. Phosphorus content decreased by 40 and 23% from early to late harvest time during 2013 and 2014 seasons, respectively. Similar decreasing patterns were observed for K, Ca and Mg content. Zinc content remained constant during 2013; however, mid-season fruit maintained higher zinc levels during 2014 season when compared to early and late harvest time. Protein content was constant for early and mid-season fruit but significantly decreased during the late harvest in both seasons. Moisture content decreased from 74.0 to 65.0% from early to late harvest during both seasons. Starch, oil and ash content were high during late harvest time in both seasons; while crude fibre was high during the mid-harvest time when compared with early and late harvest time. Internal chilling injury increased with maturity and ripening temperature. In both seasons, higher temperatures induced higher anthracnose incidences during early and mid-harvest compared with late harvest time. Similarly, vascular browning was high on fruit ripened at 16°C during early and mid-harvest time but decreased on late harvest fruit during 2013. However, low ripening temperatures induced high incidences of vascular browning during 2014 season. Stem-end rot was high on fruit ripened at 16°C than 21 and 25°C during 2014 season. xvi Physico-chemical quality parameters showed similar behaviour in both seasons. Fruit lightness increased with ripening time regardless of ripening temperature during the early harvest, but remained constant during mid and late harvest. Hue angle (h0) and Chroma (C*) values were slightly reduced during ripening. Fruit ripened at 25°C had the highest respiration rate and reached a climacteric peak earlier (day 2) than fruit ripened at 21 and 16°C (day 4). Fruit firmness and weight loss were high and rapid at 25°C followed by 21 and 16°C regardless of the harvest time. Delayed harvest had no effect on yield and fruit size. Generally, nutritional content of avocado fruit increased with fruit maturity. Furthermore, fruit maturity played a major role in the response of fruit to ripening temperature. Higher temperature enhanced fruit ripening, but was conducive for development of post-harvest diseases. Keywords: Harvesting time, nutrition, yield, fruit size, ripening temperature, post-harvest quality
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Miller, J. Joseph. "Quality and Competence: An Analysis of the Role of Mill's Qualitative Hedonism on his Conception of Representative Democracy." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/36581.
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Traditionally, John Stuart Mill has been described as a transitional thinker who fails to fully understand the values he espouses. Critics contend that he cannot simultaneously espouse both utility maximization and the protection of individual choice-making as a non-trumpable value. Like his moral philosophy, Mill’s political thought is also rejected for interspersing, seemingly at random, elements of utilitarianism with concerns about respecting individual choice-making. More recent attempts to bring Mill’s commitment to utilitarianism into line with his respect for individual choice-making are not wholly successful. In this thesis, I offer an interpretation of Mill’s moral philosophy which reconciles the tension between utility maximization and respect for individual choice-making as a non-trumpable value. In addition, I argue that my interpretation of Mill’s moral philosophy also allows us to interpret his political thought.Master of Arts
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Fahrenholz, Adam Charles. "Evaluating factors affecting pellet durability and energy consumption in a pilot feed mill and comparing methods for evaluating pellet durability." Diss., Kansas State University, 2012. http://hdl.handle.net/2097/13633.
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Doctor of PhilosophyDepartment of Grain Science and Industry
Keith C. Behnke
A series of experiments was conducted to compare methods used to evaluate the durability of animal feed pellets, as well as to investigate the potential for modeling the effects of formulation and processing factors on both pellet durability index (PDI) and pelleting energy consumption, measured in kilowatt hours per ton (kWh/ton). Seven different factors, including ground corn particle size, added fat level, inclusion of distillers dried grains with solubles (DDGS), feed rate, steam conditioning temperature, conditioner retention time, and pellet die thickness (L:D ratio) were examined. Each factor was evaluated at two levels, and treatments were developed in order that all factor to factor comparisons could be made. Pellet samples were analyzed according to the standard method as described in ASAE S269.4, a modification of this method, and by using the NHP100 pellet tester set to each of its four testing intervals (30, 60, 90, and 120 seconds). The standard method was found to provide the most consistent and repeatable determinations of pellet durability, and was found to correlate well with the modified method, as well as with the NHP100 results at 30 and 60 seconds. Physical attributes of feed pellets, such as pellet hardness, bulk density, and moisture content were found to have significant, but weak correlations with pellet quality. Pellet quality was found to be significantly influenced by all factors other than ground corn particle size and feed rate. Higher fat level, lower conditioning temperature, and the thinner pellet die most significantly lowered pellet quality, with increasing effect respectively. A regression model was developed that was able to predict pellet durability within an average of 1.1 PDI. Pelleting energy consumption was found to be significantly influenced by all seven factors, with the higher fat level, thinner pellet die, and higher conditioning temperature most improving efficiency, with increasing effect respectively. A regression model was developed that was able to predict energy consumption within an average of 0.3 kWh/ton. The successful creation of regression equations demonstrates that there is potential for modeling and optimizing pellet quality and energy consumption within a pelleting operation.
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Kandil, Mohamed Ali Mahmoud Hussein. "The effect of fertilizers for conventional and organic farming on yield and oil quality of fennel (Foeniculum vulgare Mill.) in Egypt." [S.l. : s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=964677806.
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Bragueto, Graziela. "Otimização do processo de desidratação osmo-convectiva para produção de tomate seco." Universidade Estadual do Oeste do Parana, 2013. http://tede.unioeste.br:8080/tede/handle/tede/156.
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Previous issue date: 2013-06-17The tomato (Lycopersicon esculentum Mill.) is a vegetable widely cultivated and consumed worldwide. Plantations of tomatoes intended for processing industry and fresh market. The increasing consumption of tomato can be related to be a versatile food with high nutritional value and can be eaten fresh or processed. Therefore, the aim of this research was to evaluate the processing of dried tomatoes using experimental design to obtain the best conditions and analyze the storage for sixty days seeking a quality product. We used tomato keeper variety of Revelation, in the mature stage, cleaned and cut into two pieces without seeds. After immersed in a solution prepared osmotic with sodium chloride (0 to 10%) and sucrose (3.96 to 46%) for a time from 12.8 to 267.8 minutes. Then, the tomatoes were spread on trays and placed into the dryer at temperatures from 56.6 to 73.4 °C until the moisture adequate visual. There were 17 trials, according to the central composite rotational design 23, which evaluated the effect of three factors in processing: concentration of the osmotic solution, immersion time and drying temperature. After analyzed the quality parameters color and lycopene content, and defined the optimum processing conditions to obtain the maximum, through optimization. From the optimum conditions was carried out further processing the dried tomato, which was stored in two types of packaging for sixty days and analyzed parameters of moisture, color, lycopene and vitamin C. In the drying kinetics of tomato, it was observed that the concentration of the osmotic solution had a significant influence on the moisture loss by reducing the drying time. Among the factors evaluated, the osmotic solution concentration and drying temperature had a significant effect only in the color parameters lightness, chroma index and hue angle. In parameter lycopene, the osmotic solution concentration had a significant effect. The simultaneous optimization of the responses yielded the optimum conditions for processing the dried tomatoes. The process presented overall desirability of 62.43%, and the levels of the factors set out in the following condition: the osmotic solution concentration of 15.5%, soaking time of 12.8 minutes and the drying temperature of 67 ° C. Under these conditions it was possible to obtain dried tomatoes with moisture content of 10.68%, 31.80 brightness, chroma index of 33.20, hue angle of 35.31, lycopene and vitamin C from 144.80 ug / g 4.19 mg/100 g respectively. The dried tomatoes stored for sixty days with air and vacuum packaging, no significant changes in moisture content and vitamin C. In contrast, lycopene has decreased during storage, resulting in loss of intensity and color change detected by the coordinate decrease and increase of C * h *. In addition, there was a reduction in the parameter L *, indicating the darkening of sun-dried tomatoes. Therefore, it was possible to obtain dried tomato quality.
O tomate (Lycopersicon esculentum Mill.) é uma hortaliça amplamente cultivada e consumida em mundo todo. As plantações de tomate destinam-se à indústria de processamento e ao mercado in natura. O consumo crescente desse produto pode estar relacionado ao fato de ser um alimento versátil com alto valor nutricional, podendo ser consumido in natura ou processado. Por essas razões, foi estabelecido como objetivo desta pesquisa avaliar o processamento do tomate seco, utilizando o planejamento experimental, para obter as melhores condições e analisar o armazenamento por sessenta dias, visando um produto com qualidade. Foram utilizados tomates rasteiros da variedade Ap, em estágio maduro, higienizados e cortados em duas partes sem sementes. Após, imersos em solução osmótica elaborada com cloreto de sódio (0 a 10%) e sacarose (3,96 a 46%) por um tempo de 12,8 a 267,8 minutos. Em seguida, os tomates foram distribuídos em bandejas e colocados no secador com temperaturas de 56,6 a 73,4 °C até atingir a umidade visual adequada. Foram realizados 17 ensaios, de acordo com o delineamento composto central rotacional 23, que avaliou o efeito de três fatores no processamento: concentração da solução osmótica, tempo de imersão e temperatura de secagem. Após, foram analisados os parâmetros de qualidade cor e teor de licopeno, sendo definidas as melhores condições de processamento optando-se pelos valores máximos de licopeno e chroma e menores valores de luminosidade e hue, pelo método de otimização. A partir das condições ótimas, foi realizado um novo processamento do tomate seco, o qual foi armazenado em dois tipos de embalagem por sessenta dias e analisado os parâmetros de umidade, cor, licopeno e vitamina C. Na cinética de secagem do tomate, observou-se que a concentração da solução osmótica teve influência significativa na perda de umidade com a redução do tempo de secagem. Dentre os fatores avaliados, a concentração da solução osmótica e a temperatura de secagem, tiveram efeito significativo somente nos parâmetros de cor luminosidade, índice de croma e ângulo de cor. No parâmetro licopeno, a concentração da solução osmótica teve efeito significativo. A otimização simultânea das respostas permitiu obter as condições ótimas para o processamento do tomate seco. O processo apresentou desejabilidade global de 62,43%, sendo os níveis dos fatores definidos na seguinte condição: concentração da solução osmótica de 15,5%, tempo de imersão de 12,8 minutos e a temperatura de secagem de 67 °C. Nestas condições foi possível obter tomate seco com o teor de umidade de 10,68%, luminosidade de 31,80, índice de croma de 33,20, ângulo de cor de 35,31, teores de licopeno e vitamina C de 144,80 ug/g e 4,19 mg/100g, respectivamente. O tomate seco armazenado por sessenta dias em embalagem com ar e a vácuo, não apresentou alterações significativas no teor de umidade e vitamina C. Em contrapartida, o licopeno apresentou diminuição durante o armazenamento, acarretando a perda da intensidade e mudança de cor constatada pela diminuição da coordenada C* e aumento do h*. Além disso, observou-se redução no parâmetro L*, indicando o escurecimento do tomate seco. Portanto, foi possível obter tomate seco com qualidade.
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Maboko, Martin Makgose. "Growth, yield and quality of tomatoes (Lycopersicon Esculentum Mill.)and lettuce (Lactuca Sativa L.) as affected by gel-polymer soil amendment and irrigation management." Diss., University of Pretoria, 2005. http://hdl.handle.net/2263/30487.
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Tomato and lettuce are amongst the most important fresh vegetables used in South Africa. However, growth, yield and quality of tomato and lettuce are constrained by water shortage and poor productivity of sandy soil. In South Africa, large parts of the agricultural land are in a semi-arid region and water is becoming scarcer and more costly. Recognizing the fundamental importance of water-holding amendments like gel-polymers to enhance water use efficiency and soil physical properties, this study was carried out to investigate the effects of pure gel-polymer and fertiliser-fused gel-polymer soil amendments across five irrigation intervals on growth, yield and quality of tomato (Lycopersicon esculentum Mill.) and lettuce (Lactuca sativa L.). The response of tomato growth, yield and quality to irrigation interval and gel-polymer soil amendments (pure gel-polymer and fertiliser fused gel-polymer) was conducted in a tunnel. The gel-polymer treatments were: control (sandy soil), two pure gel-polymer levels (8 and 16 g-20 L-1 sandy soil, equivalent to 400 g and 800 g-m-3) and two fertiliser fused gel-polymer levels (20 and 40 g-20 L-1 sandy soil, equivalent to 1 kg and 2 kg-m-3). Irrigation was either applied once daily or every second, third, fourth or fifth day, equivalent to 0.8, 1.25, 1.45, 1.88 and 2.29 L of water per 20 L bag of sand. Fruit mass, fruit diameter, fruit number, plant height, stem diameter, number of trusses, root fresh and dry mass, total soluble solids, fruit juice pH and titratable acidity were determined. Neither irrigation interval nor gel-polymer amendments had an influence on tomato quality (total soluble solids, pH and titratable acidity). Generally, plant yield, height, stem diameter, number of trusses, and root fresh and dry mass were increased with gel-polymer amendments compared to pure sandy soil. Regardless of irrigation interval, both fertilizer-fused gel-polymer levels appeared to be effective in improving plant growth and yield compared to pure gel-polymer, which gave good results only at the higher level of application. The study revealed that gel-polymer amendments increased productivity of tomato on a sandy soil. Similarly, the response of lettuce growth, yield and quality to gel-polymers and irrigation intervals was investigated under a tunnel conditions. The gel-polymer treatments were: control, two pure gel-polymer levels (4 and 8 g-10 L-1 sandy soil, equivalent to 400 g and 800 g-m-3) and two fertilizer-fused gel-polymer levels (10 and 20 g-20 L-1 sandy soil, equivalent to 1 kg and 2 kg-m-3). Irrigation was either applied daily or every second, third, fourth or fifth day, equivalent to 0.63, 0.83, 1.04, 1.25 and 1.46 L per 10 L plastic bags. Measurements were made of fresh head mass, head height, head circumference, head diameter, stem diameter, fresh root mass, dry root mass and dry head mass. The dried head samples were analysed for percentage tissue calcium and nitrogen. Lettuce grown on sandy soil amended with higher level of pure gel-polymer (Stock 8) and both fertiliser fused gel-polymer levels (Aqua 10 and 20) resulted in significantly higher fresh and dry head mass, head circumference, head diameter, head height, stem diameter, and fresh and dry root mass as compared to low level of pure gel-polymer (Stock 4) and sandy soil without gel-polymer (control). All irrigation intervals did not have an effect on growth, yield and quality of lettuce except at irrigation interval of every third day, which significantly lowered head circumference. Gel-polymer did not have a significant effect on percentage calcium and nitrogen concentration in the leaf tissue. Growing lettuce in soil amended with higher pure gel-polymer (Stock 8) level and both fertiliser-fused gel-polymer (Aqua 20 and Aqua 40) would likely be economically advantageous for a grower due to improved growth and higher yield of good quality lettuce.Dissertation (MSc (Horticulture))--University of Pretoria, 2005.
Plant Production and Soil Science
unrestricted
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Maboko, Martin Makgose. "Growth, yield and quality of tomatoes (Lycopersicon esculentum Mill.) and lettuce (Lactuva sativa L.) as affected by gel-polymer soil amendment and irrigation management." Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-02202007-105100.
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Ferchau, Erik, Torsten Krüger, Sophia Kiesewalter, Sabine Kunzmann, Mirko Martin, Matthias Hetze, and Karsten Nürnberger. "Qualitätssicherung dezentraler Ölmühlen - Umsetzung eines Qualitätssicherungssystems bei der Produktion, Herstellung und Anwendung von Rapsölkraftstoff." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-25389.
Full textAbstract:
In zwei sächsischen Betrieben, die selbst erzeugte Rapssaat in einer Pflanzenölmühle zu Rapspresskuchen und Rapsöl verarbeiten, wurde ein Qualitätssicherungssystem (QSS) für Ölsaaten verarbeitende Betriebe in Sachsen erarbeitet. Der in den beiden Betrieben erzeugte Rapsölkraftstoff zeigt eine für dezentrale Anlagen gleichbleibend hohe Qualität. Die Betriebe zeichnen sich durch ein spezielles Reinigungsverfahren und eine umfassende Qualitätssicherung aus.
Das bereits vorhandene QSS des Technologie- und Förderzentrums Straubing (TFZ) bildete die Grundlage für die Entwicklung des universell anwendbaren QSS. Es wurde um Fragen zum Anbau, Einsatz des Rapsölkraftstoffs, Umrüstung der Fahrzeuge, Wartung der Fahrzeuge inkl. BHKW und Einsatz des Presskuchens in der Tierfütterung erweitert und in den beiden Betrieben erprobt.
Das entwickelte QSS besteht aus Modulen und ist leicht an die betrieblichen Gegebenheiten vor Ort anzupassen.
Das QSS inklusive Handbuch und Kalkulationsmodul zur Berechnung der Wirtschaftlichkeit aller Stufen der Verwertungskette steht im Internet unter http://www.landwirtschaft.sachsen.de/landwirtschaft/7211.htm zur Verfügung.
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Kirigia, Dinah [Verfasser]. "Investigation of physiological and molecular mechanisms for quality assurance in post-harvest management of African nightshade (Solanum scabrum Mill.) and cowpea (Vigna unguiculata L. Walp) / Dinah Kirigia." Hannover : Gottfried Wilhelm Leibniz Universität Hannover, 2018. http://d-nb.info/1174302585/34.
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Kirigia, Dinah Karimi [Verfasser]. "Investigation of physiological and molecular mechanisms for quality assurance in post-harvest management of African nightshade (Solanum scabrum Mill.) and cowpea (Vigna unguiculata L. Walp) / Dinah Kirigia." Hannover : Gottfried Wilhelm Leibniz Universität Hannover, 2018. http://d-nb.info/1174302585/34.
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Alves, Laura Beatriz 1990. "Técnica de identificação de adulteração no leite via ultrassom e regras fuzzy." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/267717.
Full textAbstract:
Orientadores: Elaine Cristina Catapani Poletti, Francisco José ArnoldDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Tecnologia
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Resumo: A presente pesquisa propõe um modelo de avaliação e classificação de amostras de leite cru no tocante à sua regularidade, tendo em vista que, frequentemente, são constatadas alterações em amostras do produto comprometendo sua qualidade e sua composição. Sabido que tais adulterações, além de outras consequências, têm reflexos à saúde humana, objetivou-se desenvolver uma técnica de análise do leite sem riscos e sem interferência em suas propriedades físico-químicas. Assim, através de um equipamento de ultrassom e de um sistema de apoio à decisão, avaliou-se o coeficiente de atenuação e a velocidade de propagação de ondas do produto sob diversas diluições. Tais resultados alimentaram um sistema de apoio à decisão baseado em regras fuzzy que possibilitam o desenvolvimento de um método alternativo de análise e verificação de regularidade do produto. Com isso, foi possível confirmar a eficiência da técnica ao identificar que, com a adulteração progressiva da amostra, o coeficiente de atenuação aumenta e a velocidade de propagação diminui, desde que a amostra de referência seja a de leite cru puro
Abstract: This research proposes an evaluation and classification model of samples of raw milk in regarding its regularity, taking into consideration that frequently found changes in product samples, affecting its quality and composition. Known that such adulteration, among other consequences, have an effect on human health, it was aimed to develop a technique milk analysis without risk and without interference in their physicochemical properties. Thus, through an ultrasound equipment and a system for decision support, the attenuation coefficient and the velocity of wave propagation of the product were evaluated in different dilutions. These results supplied a system of decision support based on fuzzy rules that enable the development an alternative method of analysis and product regularly check. Thus, it was possible confirm the efficiency technique to identify, with the sample progressive adulteration, the attenuation coefficient increases and the propagation speed decreases once the reference sample is a pure raw milk
Mestrado
Tecnologia e Inovação
Mestra em Tecnologia
26
Magalhães, Ana Maria de. "Eficacia de limpeza durante o beneficiamento de tomate de mesa." [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257045.
Full textAbstract:
Orientador: Marcos David FerreiraDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola
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Resumo: A etapa de limpeza em uma linha de beneficiamento para tomate de mesa é importante, pois é responsável pela retirada de impurezas externas dos frutos, sem danificálos. O objetivo deste trabalho foi avaliar a eficácia da limpeza e a qualidade dos frutos após serem submetidos a esse processo, alterando o tipo de cerdas e as rotações das escovas utilizadas, tendo como modelo referencial o tomate de mesa Débora. Os ensaios foram realizados em laboratório, na etapa de limpeza do protótipo UNIMAC1. Primeiramente, identificou-se entre as metodologias, análise com colorímetro e turbidímetro, a mais adequada para avaliar a eficácia de limpeza. Para isto utilizou-se esferas de borracha, de peso similar ao tomate, que foram sujas artificialmente e passaram pela limpeza no protótipo com cerdas de nylon e rotação de 100 rpm. Em uma segunda etapa, avaliou-se a eficácia de limpeza, utilizando as esferas de borracha, variando-se o tipo de cerda (nylon, sisal, Tereftalato de polietileno - PET e fibra de coco) e a rotação (40, 80, 120 e 160 rpm) das escovas. E por fim, realizou-se o estudo com o tomate de mesa, analisando a eficácia da limpeza e a qualidade dos frutos (perda de massa, atividade respiratória, concentração de etileno e aparência externa). Observou-se que a análise com o turbidímetro foi a mais precisa na avaliação da eficácia de limpeza. No ensaio com as esferas, o uso de cerdas mais flexíveis, nylon e sisal, que apresentam um índice de flexibilidade (Gc) de 68,34 e 70,27 N.m-1, respectivamente, combinadas a altas rotações tornaram o processo de limpeza mais eficaz. A cerda PET, que é mais rígida, Gc de 135,94 N.m-1, e a rotação de 40 rpm foram ineficientes, apresentando um índice de limpeza inferior a 50%. Para os frutos de tomate, o tratamento cerdas de nylon a 120 rpm foi o mais eficaz no processo de limpeza, com um índice de limpeza de 91%, já na rotação de 160 rpm o índice foi inferior (88%), uma vez que devido à alta velocidade das escovas os frutos pulavam e assim não eram envoltos pelas cerdas. Os menores índices de limpeza, 75,4 e 78,8% foram obtidos nos tratamentos com fibra de coco a 80 e a 120 rpm, respectivamente. De um modo geral, os frutos limpos apresentaram alta perda de massa, alta atividade respiratória e um maior incremento na concentração de etileno após o processo de limpeza. A limpeza dos frutos não foi perceptível na análise sensorial, todavia os tomates que passaram pela limpeza foram os mais aceitos no teste de intenção de compra. Assim concluiuse que a cerda de nylon, por ser mais flexível, quando combinada à rotação de 120 rpm, envolveu melhor os frutos, tornando a limpeza mais eficaz. Contudo, tal processo aumentou a perda de massa e a atividade respiratória logo após o tratamento. Por outro lado quando combinada à rotação de 160 rpm, apesar do processo ser mais ineficiente com relação à limpeza, ocorreu menores alterações de qualidade nos frutos
Abstract: The cleaning step of a packing line for fresh tomatoes is very important, because it is responsible for removing surface residues of fruits without injuring. The main goal of this work was to evaluate cleaning efficiency and fruit quality submitted to different types of bristles and rotations, having as referential model the fresh market tomato Débora. The assays were carried out in a laboratory, in a cleaning step on a prototype developed and named UNIMAC1. First, an assay was carried out to identify the best method for evaluating cleaning efficiency: colorimeter or turbidimeter. Then, rubber spheres, with similar tomato weight, were artificially dirtied and submitted to the cleaning step on the prototype, with brushes of nylon bristles and rotation of 100 rpm. Afterwards, in a second process, the efficiency cleaning was evaluated and the rubber spheres were used again, changing the types of bristles (nylon, sisal fiber, PET and coconut fiber) as well as the rotation (40, 80, 120 and 160 rpm) of rotary brushes. The last phase, the studies were carried out with fresh tomatoes for evaluating cleaning efficiency and fruit quality (weight loss, respiratory rate, ethylene evolution and external appearance). Results showed that the turbidimeter method was the most accurate methodology for evaluating cleaning efficiency. On the trials where rubber spheres were used, the flexible bristles, nylon and sisal fiber, which demonstrated a flexible index (Gc) of 68.34 and 70.27 N.m-1, respectively, were more efficient at higher rotations. PET bristles, that are stiffer (Gc of 135.94 N.m-1) and at a rotation of 40 rpm, were inefficient, presenting a cleaning index lower than 50%. For the fresh tomatoes, a nylon brush at 120 rpm treatment was the most efficient cleaning process, showing a cleaning index of 91%. Nylon brushes at 160 rpm treatment showed the lowest cleaning index (88%). These results were probably associated to the fact that, at higher speeds, fruits tended to jump, causing a poor contact between bristles and fruits. The lowest cleaning index, 75.4 and 78.8%, were observed on coconut fiber at 80 and 120 rpm treatments, respectively. In general, cleaned fruits demonstrated high weight loss, high respiratory rate and more evolution of ethylene after cleaning process. Cleaning efficiency of fruits was not perceptible in sensory analysis; however tomatoes that were submitted to cleaning were more accepted by the buy intention test, being the clean fruits in coconut fiber at 80 rpm treatment preferred by buyers. In conclusion, as nylon bristles are more flexible, allowing a more intimate contact with fruits at 120 rpm, the cleaning process for these parameters is more efficient. However this treatment increased weight loss and respiratory rate after cleaning. On the other hand, nylon at 160 rpm treatment showed to be more inefficient in relation to cleaning, but showed fewer fruits alterations
Mestrado
Tecnologia Pós-Colheita
Mestre em Engenharia Agrícola
27
Mader, Erin F. "Utilizing DDGS and crude glycerol in animal diets: feed manufacturing considerations." Thesis, Kansas State University, 2011. http://hdl.handle.net/2097/7066.
Full textAbstract:
Master of ScienceDepartment of Grain Science and Industry
Leland McKinney
Three experiments were conducted to evaluate value added uses for dried distillers grains with solubles (DDGS) and crude glycerol in swine and poultry diets. In Exp.1, crude glycerol from multiple biodiesel production facilities was evaluated for storage and variability characteristics. Part one reviewed the storage capabilities of crude glycerol at room temperature and excessive heat conditions on ferrous and stainless steel metal. There was no notable corrosion during the two-month experiment for either metal type under each condition. There was a slight discoloration observed on the ferrous metal stored under excessive heat conditions, but no pitting or sign of corrosion was noted. No changes were observed in the stainless steel under either environment condition. Part two evaluated the variability of crude glycerol from multiple biodiesel production facilities. Representative samples of the parent feedstock and resultant glycerol was collected an analyzed. There was considerable variation between samples, particularly when comparing glycerol from the different feedstocks (vegetable vs. animal). Exp. 2 and 3 took place in the Feed Processing Research Center in the Department of Grain Science at Kansas State University. Pellet quality and electrical energy consumption was evaluated by reviewing production rate, conditioning and hot pellet temperatures, motor load, and pellet durability index (PDI) as testing parameters. In Exp. 2, diets containing varying levels of crude glycerol were evaluated on pellet quality and pellet mill performance in a pilot mill and in a commercial facility. For part one, a corn-soy based swine grower diet was formulated to contain 0, 3, 6, and 9% crude glycerol. Each diet was steam conditioned to 150, 170 and 190 °F in an atmospheric conditioner and pelleted. An interaction existed between glycerol and conditioning temperature. For all diets containing glycerol, roll skid occurred and the pellet mill plugged as conditioning temperature approached 190°F. Pellet quality increased linearly (P < 0.01) with increasing levels of glycerol. Part two took place at Don’s Farm Supply in Newell, IA. A corn-soy based turkey grower diet was formulated to contain 3% glycerol and pelleted. Results from part two were consistent with part one, in that there was an interaction between conditioning temperature and the addition of glycerol. Exp. 3 evaluated DDGS on pellet quality and electrical consumption. A poultry diet was formulated to contain 0, 15, or 30% DDGS and steam conditioned to 140, 160, and 180°F. As conditioning temperature increased, pellet quality in diets containing DDGS significantly improved (P>.001). Electrical consumption in diets containing DDGS compared to the control showed no significance in reduction in energy usage (P>.001). In conclusion, the production of pelleted diets containing crude glycerol is a feasible option; however, conditioning temperatures should be kept minimal and storage and variation of the material should be considered. In addition, improved pellet quality in pelleted diets containing DDGS is in part by conditioning at higher temperatures, respectively. The data suggests that the addition of crude glycerol and DDGS in animal diets can serve as a beneficial feed additive.
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Andreuccetti, Caroline. "Avaliação da qualidade do tomate de mesa tratado co gas etileno." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257194.
Full textAbstract:
Orientador: Marcos David FerreiraDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola
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Resumo: O tomate é uma das principais hortaliças cultivadas no Brasil. Procurou-se a partir de duas cultivares avaliar a qualidade pós-colheita desses frutos, colhidos no estádio de amadurecimento verde-maduro, submetidos ao tratamento com gás etileno. As cultivares utilizadas foram Débora e Andréa. O tratamento utilizado foi realizado a partir de mistura gasosa, etil 5% diluído em ar comprimido, fluxo dinâmico por 48 horas à temperatura ambiente de 20º±1ºC e umidade relativa de 90±5%. A concentração final da mistura permaneceu ao redor de 100µL.L-1, a qual foi monitorada por meio de cromatografia gasosa. Após término da aplicação do etileno, os tomates foram armazenados sob duas temperaturas. Um lote permaneceu a 20º±1ºC e outro foi mantido a 12,5º±1ºC. Tomates não tratados com etileno foram mantidos nas mesmas condições de temperatura e umidade relativa. Para os experimentos, foram realizadas, após cada alteração no estádio de amadurecimento do tomate, as análises: índices de coloração (L*, a* e b* e suas relações), perda de massa, determinação do índice de firmeza (N.mm-1), sólidos solúveis (°Brix), acidez titulável (g.100g-1), pH e ácido ascórbico (mg.100g-1). Quando os tomates atingiram o estádio de amadurecimento vermelho foram realizadas análises sensoriais, com teste de aceitabilidade e escala de intensidade. As cultivares responderam de forma diferente aos tratamentos, conforme as características intrínsecas de cada uma. A aplicação de gás etileno promoveu maior uniformidade de coloração nos frutos tratados. No entanto influenciou também nos resultados de a*, b*, perda de massa, sólidos solúveis e firmeza para cultivar Débora e b* para cultivar Andréa. Frutos armazenados à temperatura de 20ºC demonstraram maior porcentagem de perda de massa ao longo do amadurecimento, com média 3,02% para cultivar Débora e 2,60% para cultivar Andréa. Os resultados de acidez titulável, 0,38g.100g-1 para cultivar Débora e 0,42g.100g-1 para cultivar Andréa e; sólidos solúveis foram maiores para frutos armazenados a 12,5ºC, com média de 4,85ºBrix para cultivar Andréa e frutos armazenados a 20ºC, com 4,42ºBrix para cultivar Débora, com ou sem tratamento com gás etileno. Na média os valores de ácido ascórbico foram mais elevados para a cultivar Andréa não apresentando, entretanto, diferença significativa entre os tratamentos
Abstract: Tomatoes are one of the most important vegetable crops cultivated in Brazil. Post harvest quality of tomatoes was evaluated in two cultivars, harvested at mature green stage, and submitted to ethylene treatments. Cultivars used were Débora and Andréa. Treatments were accomplished using a gas mixture with ethyl (5%) diluted in compressed air, flow through for 48 hours at temperature of 20º±1ºC and relative humidity of 90±5%. Ethylene final concentration of the mixture remained around 100µL.L-1, which was monitored through gas cromatography. After ethylene application, tomatoes were stored at two temperatures. One lot remained at 20º±1ºC and another one was kept at 12.5º±1ºC. Control fruits were kept in the same storage conditions of temperature and relative humidity. For each maturity color change, the following analyses were carried out: color indexes (L *, a* and the b * and its relations), water loss (%), fruit firmness (N.mm-1), soluble solids (°Brix), titratable acidity (g.100g-1), pH and ascorbic acid (mg.100g-1). Red tomatoes were submitted to sensoryal analyses, with affective test and acceptability. Cultivars responses were different according to the distinct treatments, as an answer for the intrinsic characteristics of each one. Ethylene application promoted color uniformity in treated fruits, also influencing the results for a*, b*, water loss, soluble solids and firmness to cultivar Débora and b* to cultivar Andréa. Fruits stored at 20ºC showed higher water loss (%) during storage, 3.02 and 2.60%, cv. Débora and cv. Andréa, respectively. Titratable acidity results were, 0.38g.100g-1 for cv. Débora and 0.42g.100g-1 for cv. Andréa; soluble solids was higher for cultivar Andréa stored at 12.5ºC, means of 4.85ºBrix and for cv. Débora in fruits stored at 20oC, means of 4.42ºBrix, for both treatments with and without ethylene. Ascorbic acid values were higher for Andrea than for Debora fruits. However did not show significant difference among treatments
Mestrado
Tecnologia Pós-Colheita
Mestre em Engenharia Agrícola
29
Carlsson, Fredrik. "On impacts and ride-through of voltage sags exposing line-operated AC-machines and metal processes." Doctoral thesis, KTH, Electrical Systems, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3681.
Full textAbstract:
During the last decade, power quality has been recognised asa global problem. Among different types of power qualityproblems, voltage sags have been identified to be one of themost severe problems for different process industries. The mostcommon reason to voltage sags is lightning strikes in powerlines. Protection equipment, usually located at switchyards,disconnect faulted power lines as soon as possible, which isapproximately 100 ms. Thus, the duration of voltage sags areapproximately 100 ms. The sensitivity to voltage sags ofelectrical equipment in process industries can be observed asfor instance malfunction, automatic turnoff or damages.
This thesis gives an overview of three metals processes withfocus on the sensitivity to voltage sags and interruptions. Theinherent energy in the process is used to find the sensitivity.This energy may also be used to obtain "ride-through" for theprocesses. The three metals processes are a blast furnaceprocess, a hot rolling mill process and a cold rolling millprocess. The main attention in this thesis is paid to the blastfurnace process, which is powered by a line-operatedsynchronous machine.
The thesis shows that the protection equipment forelectrical machines can be adjusted to avoid unnecessaryshutdowns. It is also explained why there are high torque andcurrents during voltage sags as well as after voltage sags. Itis shown that the first peak torque and current during thevoltage sags is almost proportional to the voltage change, thatis the voltage magnitude before the voltage sag minus thevoltage magnitude during the voltage sag. The first peak torqueand current after the voltage sag depends sinusoidal-like onthe duration of the voltage sag and almost proportional to thevoltage change during the voltage sag. There is no fluxsaturation during voltage sags, however after voltage sagssaturation is very likely to occur. The thesis explains why andalso how the flux is changed during and after voltage sags.
The duration of voltage sags is in many cases set by theprotection equipment located in switchyards. It is shown thatthe durations of voltage sags can be changed to durations thatwill cause less peak torque and current after voltage sags forline-operated AC-machines. It is also shown how this istheoretically achieved.
Keywords:Rolling mill, Blast furnace, Power Quality,Synchronous machine, Asynchronous machine, Voltage sag, Voltageinterruption, Ride-through, Process disturbances, Simulation,Modelling
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Inam, Muhammad Asif. "Particle sizing and product quality in production of fine and nano particles by means of wet grinding process." Thesis, Toulouse, INPT, 2010. http://www.theses.fr/2010INPT0028/document.
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Le procédé de broyage en voie humide est une opération intéressante permettant la production de particules fines ou de nanoparticules. La caractérisation de la taille des particules est une donnée essentielle pour l'interprétation des données, le contrôle et l'optimisation de ces procédés selon divers aspects. Il y a un manque de connaissances relatif à la caractérisation de la taille de particules en relation avec les procédés de broyage en voie humide. Cette caractérisation est spécifique pour différentes raisons. (i) Les dispersions traitées par broyage contiennent souvent des impuretés et (ou) des additifs. Nous savons assez peu comment les impuretés et les additifs influencent la taille des particules en suspension dans ces procédés. (ii) Lors de procédés de broyage en voie humide, des dispersions de différentes concentrations peuvent être utilisées. Il est important de savoir comment la concentration de la dispersion peut influencer la mesure de la taille des particules lors du procédé. (iii) La modification de la taille moyenne des particules, résultant de leur fragmentation, est rapide. (iv) Le degré de polydispersité dans le produit change au cours du temps. (v) La nature des interactions entre les particules change; avant broyage les particules sont non-colloïdales, elles le deviennent après un certain temps d'opération. De même, il y a un manque de connaissances permettant de comprendre comment la qualité du produit broyé final est affectée lors du broyage. Dans cette étude nous explorons plusieurs aspects de la caractérisation de taille et de la qualité du produit au cours d'un procédé de broyage en voie humide du CaCO3, réalisé à l'aide d'un broyeur à billes agité. La spectroscopie acoustique qui est une technique connue pour ses potentialités en matière de caractérisation de taille de dispersions en ligne, sous des conditions réelles de procédés et sans nécessiter une dilution des échantillons, a été utilisée dans cette étude en complément de la diffusion dynamique de la lumière. Ce travail a montré sous quelles conditions les effets des impuretés et des additifs etc. sur la taille des particules en suspension pouvaient être déterminés par spectroscopie acoustique. De plus, nous avons comparé et analysé les résultats des mesures de taille obtenus avec les deux techniques. Les différences observées ont été analysées. Nous avons montré que la diffusion multiple observée à forte concentration en solide lors des procédés de broyage en voie humide pouvait conduire à une mauvaise interprétation des résultats relatifs à la taille des particules. En outre, la qualité est un concept relatif. Dans ce travail, nous avons adopté une démarche pour mesurer les effets de différents paramètres sur les caractéristiques du produit broyé en se basant sur une définition de la qualité telle que dans la norme ISO 9000 :2005. La démarche a permis de prendre en compte différents paramètres opératoires importants (tels que les conditions de fonctionnement du broyeur, la mesure de la taille des particules et les propriétés du matériau), ainsi que différentes propriétés caractéristiques du produit (comme la taille moyenne des particules, la largeur de la distribution de taille, la stabilité de la dispersion, le taux d'impuretés, l'énergie spécifique apportée au système et l'apparence visuelle du produit). Nous avons montré que nous pouvions établir une relation entre les paramètres opératoires et différentes qualités de produits obtenus par un procédé de broyage en voie humideWet grinding process is an interesting means of producing fine and nano particles. The particle sizing plays an important role in interpretation, control and optimization of various aspects of the wet grinding process. There is a lack of knowledge in understanding different aspects of particle sizing during a wet grinding process. The particle sizing in a wet grinding process is typical in the sense: (i) The dispersions in a wet grinding process, often, involve additives and (or) impurities. It is less known how impurities and additives influence the particle size of the dispersions in the wet grinding process. (ii) In a wet grinding process, dispersions of different concentrations may be used. It is less known how dispersions of different concentration may influence the particle sizing in a wet grinding process. (iii) In a wet grinding process, the change in average particle size of the product is rapid due to relatively fast breakage of the particles. (iv) The degree of poly dispersity in product changes with grinding time. (v) The nature of interaction between particles is non-colloidal before grinding process; this interaction becomes colloidal after a certain grinding time. Similarly, there is a lack of knowledge to understand how quality of final ground product is influenced in a wet grinding process. This study investigates the different aspects of particle sizing and product quality of aqueous dispersions of CaCO3 in a wet grinding process carried out in a stirred media mill. Acoustic attenuation spectroscopy that is known for measuring particle size of dispersions on line, under real process conditions and without diluting the sample has been employed in the study in addition to the technique of dynamic light scattering. The study brings out the conditions in which the effects of impurities and additives etc. on particle size of the dispersions may be determined using acoustic attenuation spectroscopy. Furthermore, the study compares and analyze the particle sizing results obtained though acoustic attenuation spectroscopy and dynamic light scattering. The causes of differences in the results of two techniques have been investigated. We report presence of multiple scattering at high concentration of the dispersions during wet grinding process that result in misleading results of the particles sizes. Quality is an intangible concept. In order to understand how different operating parameters influence product quality, we propose a method based upon the definition of quality as defined in ISO 9000:2005. The method takes into consideration the important operating parameters of wet grinding process (such as the operating condition of the mill, the measurement of particle size and the material) and important product characteristics ( such as average particle size, range of width of particle size distribution, stability of dispersion, degree of impurities, specific energy input and physical appearance). We bring out how a relationship between operating parameters and products of different grades may be established in a wet grinding process
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Querengässer, Julia. "Studies on milk flow, milk yield and milk quality from teats with milk flow disorders /." [S.l.] : [s.n.], 2002. http://www.stub.unibe.ch/html/haupt/datenbanken/diss/bestell.html.
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Flatt, Michelle. "Improving udder health and milk quality /." Click here to view, 2009. http://digitalcommons.calpoly.edu/dscisp/9.
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Thesis (B.S.)--California Polytechnic State University, 2009.Project advisor: Leanne Berning. Title from PDF title page; viewed on Jan. 21, 2010. Includes bibliographical references. Also available on microfiche.
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Rutaro, Hamid. "Milk quality analysis in Southwestern Uganda." Thesis, Kansas State University, 2015. http://hdl.handle.net/2097/19011.
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Master of AgribusinessDepartment of Agricultural Economics
Vincent Amanor-Boadu
As the dairy industry faces the future, consumers’ demand for better milk quality and safety is increasing. Milk quality is of major interest to both consumers and dairy farmers alike. However, scientific data on milk quality in terms of somatic cell count (SCC) in Uganda and most developing countries has been lacking. This study used SCC to compare Southwestern Uganda’s milk quality against international standards. The study also sought to assess dairy farmers’ perceptions about milk quality. Milk samples were obtained from 100 farms in Mbarara and Kiruhura districts, the major cattle corridor in Uganda. The milk’s SCC was analyzed using a DeLaval DCC. A structured questionnaire surveyed farmers on milking procedures and milk-quality perception. Descriptive statistics and qualitative analysis was used to characterize and compare milk quality against the international benchmark. The study found that the 100 farms had an average SCC of 507,000 cells/ml. About 34% of farms in the study had SCC under 200,000 cells/ml, an indication of high-quality milk. Excluding 7% of the farms with SCC over 1,000,000 cells/ml, the remaining 93% had an average SCC of 276,000 cells/ml, a level comparable to international standards, well below the EU threshold of 400,000. The study also revealed that 98% of farmers considered milk quality as important or very important both to them and to the milk buyers. However, all farmers reported that they currently do not receive a milk-quality premium and are not penalized for poor quality. Seventy-nine percent of farmers reported the cooperative they belong to as their main source of information on management practices. An improved perception of milk quality both domestically and internationally will benefit Uganda’s dairy farmers and its dairy industry at large. Consumers must be assured that Uganda’s dairy industry, its government, industry stakeholders such as the Dairy Development Authority, the Uganda National Bureau of Standards, and the private sector place the utmost importance on the quality and safety of milk and other dairy products. New technologies to measure for SCC and strict food safety regulations will help improve the country’s milk-quality image, allowing Uganda’s dairy industry to tap into major milk export markets. Most developed countries have seen increased raw-milk quality or reduced SCC as a result of strong regulatory pressure.
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Sart, Sarula. "Temperament and milk quality in sheep and cattle." University of Western Australia. School of Animal Biology, 2005. http://theses.library.uwa.edu.au/adt-WU2006.0030.
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[Truncated abstract] It is well known that cows produce more milk if they are comfortable at milking, because stress from milking may cause them milk ejection problems. Temperament is an intrinsic characteristic of the animals so may affect the level of comfort at milking, and stress from the milking process itself may have a greater impact on animals with nervous temperament than on those of nervous temperament. When the milking becomes a stressor, it may affect secretion of milk ejection hormones that, in turn, may affect milk yield and composition. There is little evidence for how animal temperament affects milk quality in different farm animals. In this thesis, I have examined the effects of temperament on quantity and quality of the milk from Merino ewes and Holstein cows. I also tested whether temperament affected the processing performance (clotting properties) of the milk from Merino ewes. The general hypotheses tested were: 1. Calm ewes would produce more milk of better quality than nervous ewes, and, consequently, the clotting properties would be better in the milk from calm ewes than from nervous ewes. 2. Calm cows would produce more milk of better quality than nervous cows.
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Stergiadis, Sokratis. "Effect of dairy management on milk quality." Thesis, University of Nottingham, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.514468.
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Sterrett, Amanda E. "Management and technology solutions for improving milk quality." UKnowledge, 2013. http://uknowledge.uky.edu/animalsci_etds/27.
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Mastitis is one of the most common and expensive dairy cattle diseases. Mastitis prevention and management are key factors in herd health and improved milk quality. One objective of this research was to evaluate management solutions to maintain a low somatic cell count, based on survey responses from Kentucky dairy producers. Because hyperkeratosis may increase mastitis incidence, another objective of this research was to examine changes in teat end hyperkeratosis in a herd transitioning from a standard pulsation milking system to an individual quarter pulsation milking system. The last objective of this research was to evaluate technologies that monitored rumination time, neck activity, reticulorumen temperature, and milk yield as potential mastitis detection devices.
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Fisher, Llewellyn Glenn. "An investigation into the occurrence, growth properties and characteristics of psychrotrophic coliform organisms in refrigerated pasteurised bovine milk in the Western Cape." Thesis, Peninsula Technikon, 1999. http://hdl.handle.net/20.500.11838/2019.
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Thesis (BTech (Food Technology))--Cape Technikon, 1999.The Dairy industry, one of the larger food industries in South Africa processes probably the most perishable and possibly the most regulated foodstuff, namely mille The unique combination of vitamins, proteins, carbohydrates, lipids, moisture and near neutral pH, offers a suitable environment for the proliferation of microbes. Milk is therefore highly susceptible to microbiological activity resulting in the irreversible spoilage of this food (Frazier & Westhoff, 1988). The coliform group of organisms comprises all aerobic and anaerobic, gram-negative, non-spore-forming rods that are able to ferment lactose with the production of acid and gas at 32°C within 48 hours (Richardson, 1985). The primary purpose of the coliform detection test is to measure the quality of the practices used to minimise bacterial contamination of processed dairy products (Richardson, 1985). IDF Standard 132A: (1991) defines psychrotrophic organisms as organisms forming countable colonies when incubated aerobically at 6.5°C for 10 days under the conditions specified in IDF standard 101A. Shelf-life tests conducted in the fresh milk laboratory of a processing plant, revealed significant growth of coliforms in samples stored at 5°C. Luch, (1985) reported that other contaminating psychrotrophs together with the coliforms reduce the shelf-life of the milk when the storage temperature thereof is above 10°C.
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Wedholm, Anna. "Variation in milk protein composition and its importance for the quality of cheese milk /." Uppsala : Dept. of Food Science, Swedish University of Agricultural Sciences, 2008. http://epsilon.slu.se/200813.pdf.
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Ayers, Carolyn. "Effect of k-casein glycosylation on the properties of milk." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=26234.
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A study was conducted to determine the relationship between the degree of glycosylation of $ kappa$-casein (CN) and physicochemical properties of milk: heat stability and ethanol stability. Morning milk samples from individual Holstein cows (genotype $ kappa$-CN AA, $ beta$-CN A$ sb1$A$ sb2$, $ alpha sb{ rm s1}$-CN BB, $ beta$-lactoglobulin AB) in midlactation were collected and analyzed for protein and somatic cell count. Samples of low somatic cell count ($<$150000 cells/ml) were skimmed and dialyzed overnight at 4$ sp circ$C against bulk tank milk to equilibrate soluble components. Three series of analyses were performed for the determination of thermostability of milk between pH 6.5 and 9. In the first 2 sections (A and B), the heat clotting time vs pH (HCT/pH) profiles of normal milk were measured. The effect of sialic acid (NANA) depletion on the HCT/pH profile was tested in a third series of experiments. And finally, a series of analyses were performed to determine the ethanol stability of milk. (Abstract shortened by UMI.)
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Kyozaire, Joan Kitiibwa. "Microbiological quality of goat milk obtained under different production systems." Diss., Electronic thesis, 2003. http://upetd.up.ac.za/thesis/available/etd-03232005-130646/.
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Allies, Bonita. "Bacteriological quality control of milk production in the Swartland Municipal Area." Thesis, Stellenbosch : Stellenbosch University, 2007. http://hdl.handle.net/10019.1/21426.
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Thesis (MPA)--University of Stellenbosch, 2007.ENGLISH ABSTRACT: The aim of this thesis was to determine in terms of policy analysis why the bacteriological quality of milk in a particular area did not comply with statutory provisions during production. The policy issue is very complex due to the diversity of conditions that exist during the milking process, which may impact on the levels of bacteria in milk. Considering this diversity, various problematic conditions are likely to cause the bacteriological contamination of milk. Milk is regarded as safe for human consumption when laboratory quality tests indicate its bacteriological suitability. Intervention on the basis of milk control should assure that milk is produced and distributed within acceptable bacteriological levels. The ad hoc milk safety strategy of the West Coast District Municipality (WCDM) was found to be inappropriate for the effective control of hygienic conditions during milk production. The existing strategy does not provide for suitable programmes to deal with this complex issue of policy and the suggestion is that it should be reviewed. Judged on the basis of success factors, a decline in milk bacteriological quality for the WCDM area revealed factors that were not effectively controlled during milk production. During the research period the hygienic quality of milk from the WCDM area was regulated and judged primarily by means of laboratory quality tests. Food safety requires much more than merely relying on quality tests. It is imperative that milk laboratory analyses should in all instances be harmonised by means of an evaluation of hygiene and sanitary conditions during production. How the problem situation with regard to milk quality is approached defines the implementation of strategy. The Environmental Health Practitioners (EHPs) of the WCDM have been implementing the requirements of applicable legislation, but each according to an individual approach. Such modi operandi provide for inconsistency in the execution of any policy. Implementing policy should be relevant, specific and adequate and should be target based. Consequently, the modification of policy is required to the extent of changing the approach when it does not comply with the afore-mentioned criteria, strategy or policy governing milk safety. More could be done by the WCDM to manage problems at milking sheds that is associated with the bacteriological quality of milk. Management control strategy is perceived to be inadequate and coupled with a lack of willingness to tackle the crux of the problem. Implementing legislative policy necessitate an objective approach coupled with an appropriate strategy. The findings of the empirical analysis together with a discussion of the implementation of the WCDM milk control strategy explains the shortcomings that was experienced in that regard. Therefore, an improved policy framework is proposed for controlling milk safety at milking sheds. In addition, a strategic framework is also proposed to administer the milk safety policy by way of programmes.
AFRIKAANSE OPSOMMING: Die doel van hierdie tesis was om, in terme van openbare beleidsanalise, te bepaal waarom die bakteriologiese kwaliteit van melk in ’n spesifieke gebied tydens die produksie daarvan nie aan die wetlike standaarde voldoen het nie. Hierdie beleidsvraagstuk word as kompleks beskou weens die uiteenlopende toestande wat tydens die melkproses ontstaan en wat ‘n impak op die bakterievlakke van melk kan hê. Inaggenome van hierdie diversiteit kan die besmetting van melk waarskynlik deur verskeie probleemtoestande veroorsaak word. Melk word geag veilig te wees vir menslike gebruik wanneer laboratoriumkwaliteittoetse op die bakteriologiese geskiktheid daarvan aandui. Ingryping op grond van melkbeheer moet verseker dat melk binne die aanvaarde bakteriologiese vlakke geproduseer en verskaf word. Die ad hoc melkveiligheidstrategie van die Weskus Distrik se Munisipale (WDM) gebied is onvoldoende bevind vir die effektiewe beheer van higiëniese toestande tydens melkproduksie. Hierdie strategie maak nie voorsiening vir geskikte programme om hierdie komplekse beleidsvraagstuk te hanteer nie en die hersiening daarvan word voorgestel. Geoordeel aan die hand van suksesfaktore, dui ‘n afname in die kwaliteit van melk vir die WDM gebied op faktore wat tydens melkproduksie nie effektief beheer was nie. Die higiëniese kwaliteit van melk binne die WDM gebied was tydens die navorsingstydperk primêr deur middel van laboratoriumkwaliteittoetse gereguleer en geoordeel. Voedselveiligheid vereis dat daar egter op meer as kwaliteittoetse gesteun word. Dit maak dit noodsaaklik dat die laboratoriumanalises van melk in alle gevalle aan die hand van evaluering van higiëniese en sanitêre toestande tydens melkproduksie geharmoniseer word. Die manier waarmee die probleemsituasie met betrekking tot melkkwaliteit benader word, definieer die implementering van strategie. Die Omgewingsgesondheidspraktisyns (OGPs) van die WDM het die voorskrifte van die toepaslike wetgewing geïmplementeer, maar elkeen volgens ‘n eie benadering. ‘n Sodanige modus operandi maak voorsiening vir die inkonsekwente uitvoering van enige beleid. Die implementering van beleid moet relevant, spesifiek, geskik en moet doelgerig wees. Gevolglik waar voornoemde kriteria, strategie of beleid wat melkveiligheid aangaan nie nagekom word nie, noodsaak dit derhalwe ‘n aanpassing van beleid vir soverre die benadering tot strategie vir melkveiligheid geraak word. Die WDM kan meer doen om probleme wat verband hou met die bakteriologiese kwaliteit van melk by melkstalle te bestuur. Die beheerstrategie van die bestuur word as onvanpas beskou en dit gaan gepaard met ‘n gebrek aan ywer om die essensie van die probleem aan te spreek. Die inwerkingstelling van wetgewing noodsaak ’n objektiewe benadering gepaardgaande met ’n geskikte strategie vir die uitvoering van beleid. Die bevindinge van die empiriese analise tesame met ’n bespreking aangaande die implementering van die WDM melkbeheerstrategie bied ’n verduideliking van die tekortkominge in daardie verband aan. Derhalwe word ’n verbeterde beleidsraamwerk voorgestel om die melkveiligheid by melkstalle te beheer. Daarbenewens word ’n strategiese raamwerk om die melkveiligheidbeleid deur middel van programme te uit te voer, ook voorgestel.
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Nolan, Derek T. "AN EXAMINATION OF MILK QUALITY EFFECTS ON MILK YIELD AND DAIRY PRODUCTION ECONOMICS IN THE SOUTHEASTERN UNITED STATES." UKnowledge, 2017. http://uknowledge.uky.edu/animalsci_etds/71.
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Mastitis is one of the most costly diseases to dairy producers around the world with milk yield loss being the biggest contributor to economic losses. The objective of first study of this thesis was to determine the impacts of high somatic cell counts on milk yield loss. To accomplish this, over one million cow data records were collected from Southeastern US dairy herds. The objective of the second study was to determine optimum treatment cost of clinical mastitis by combining two economic modeling approaches used in animal health economics. The last objective of this thesis was to determine how much Southeastern US dairy producers are spending to control milk quality on farm and determine if they understand how milk quality affects them economically. This was accomplished through a collaborative project within the Southeast Quality Milk Initiative.
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Shao, Yanwen 1967. "High pressure treatment for enhancing safety and quality of raw milk cheese." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=79123.
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The application of high pressure (HP) processing on raw milk cheese was investigated in order to assure safety and improve quality. Fresh raw milk cheese inoculated with contaminant, spoilage and pathogenic microorganisms (Escherichia coli K-12, E. coli O157:117 and Listeria monocytogenes), as well as natural micro-flora, were subjected to UP treatment at selected pressures (200--400 MPa) for various holding times (0 to 100 min), or number of pulses. HP destruction of microorganisms followed the dual effect destruction behavior involving a step change in the population due to a pressure pulse (pulse effect, PE) and a first order rate log-linear kinetics during the pressure hold. The pressure dependency of kinetic parameters followed the pressure destruction time (PDT) and Arrhenius type models.The results suggest that high pressure treatment as a powerful tool for microbial control do not result in major change in raw milk cheese quality properties (color and texture). It would thus be an effective method of inactivation of spoilage bacteria and pathogens for ensuring safety and keeping the quality of raw milk cheese.
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Gott, Paige N. "Impact of milk cessation method on intramammary infections at calving and milk yield and quality in the subsequent lactation." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1449095578.
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O'Hare, W. T. "In vitro digestibility of heat-treated milk proteins and infant formulae." Thesis, University of Salford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376878.
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Joshi, K. H. "Determining the quality of pasteurised and homogenised cow milk using microwave sensors." Thesis, Liverpool John Moores University, 2018. http://researchonline.ljmu.ac.uk/9350/.
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More than 6 billion people worldwide consume milk and milk products and this number is rapidly growing every year (FAO, 2015a), there are numerous occurrences where the milk quality was below acceptable standards causing severe health hazards among consumers including young children. The aim of this research work is to design and develop a novel, microwave spectroscopy, approach for determination of overall quality of milk. In particular, this quality determination of milk products was achieved by identification of deterioration or spoilage of milk over time, classification of the milk product based on composition (e.g. fat content), in addition to the contamination (e.g. adulteration due to presence of detergents, urea). An extensive literature review was carried out to establish the scope of the PhD work and in order to achieve the objectives. Current advancements were studied along with the traditional methods of milk quality testing to identify the key areas where further development can take place to enable the quality control of milk products outside the laboratory premises. This work addresses the drawbacks in currently employed methodologies and attempts to overcome or minimize their overall limiting effect. The application of this sensor system is aimed within the milk supply-chain hierarchy after the production at dairy plants and before sale to allow easy and real-time quality testing. The dielectric property tests were conducted to produce unique spectral signatures for three mainly consumed categories of fresh milk; whole milk, semi-skimmed milk and skimmed milk bought from a supermarket over a period of a week, which served to build a reference database. Based on these spectral signatures for the three categories of milk, a planar, microwave resonator sensor acting as a fluidic sensor was designed, simulated and fabricated to determine spoilage, classification of milk and identify presence of contamination. This work has achieved distinct results to verify the statement, followed by validation, to serve as a platform for the establishment of a laboratory based prototype model to test overall quality of milk products, with coefficient of determination R2 ≥ 0.95 in all experimental measurements.
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Enger, Kellie M. "The Impact of Parlor Equipment and Milking Procedures on Milk Quality in the Southeast US." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/89634.
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Milk quality has continued to improve over the last several decades in the US, but still remains to be a problem for dairy producers in the southeast (SE) US. The purpose of these analyses was to evaluate associations between parlor equipment function, milking procedures, and bulk tank somatic cell count (BTSCC) and bulk tank standard plate count (BTSPC) on SE US dairy farms. Data from dairies in Virginia (n = 96), Kentucky (n = 96), Tennessee (n = 84), and Mississippi (n = 7) were collected at a single visit for each farm. Monthly BTSCC and BTSPC data were retrieved from state regulatory offices for (n = 263) farms, and averaged over the 12 months prior to each farm visit and used as the dependent variables in each analysis in a backwards elimination regression model. Increased herd size was associated with lower BTSCS, but higher BTSPC. Utilization of an internal teat sealant was associated with lower BTSCS. Farms that housed cows exclusively on pasture had greater BTSCS than farms that keep lactating cows in confinement with no pasture access. Utilization of a freestall for lactating cow housing was associated with lower BTSCS. The likelihood of future dairy operation in 10 years as reported by the farm owner or manager influenced BTSPC. Beginning water temperature of the detergent wash cycle was found to influence BTSCS. These findings suggest that the most influential variables explaining milk quality are herd demographic information and farmer perceptions as well as a few management variables such as the use of an internal teat sealant and beginning water temperature of the detergent wash cycle. These findings suggest that farmer perceptions and attitudes may be influencing milk quality more than previously thought. Further research is needed to evaluate social factors that could be influencing milk quality. Milking equipment function has improved substantially over the last several decades and was not found to significantly influence milk quality among the evaluated SE US dairies in these analyses. Milking procedures such as pre- and post-milking teat disinfection are widely accepted by most dairies in the US. Minimal differences were found between milking procedures such as teat disinfectant active ingredient or using paper towels versus cloth towels suggesting that these factors may not be the most influential factors influencing milk quality.MS
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Louw, Celmarie. "Factors influencing the bacteriological quality of raw milk produced on dairy farms in Central South Africa." Thesis, Bloemfontein : Central University of Technology, Free State, 2013. http://hdl.handle.net/11462/204.
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Thesis (M. Tech. (Environmental health)) - Central University of technology, Free State, 2013Introduction Dairy farms in central South Africa produce a substantial amount of milk, which is sold in Bloemfontein, Free State. Large volumes of unpasteurized (raw) milk is collected on the dairy farms, which undergoes further processing before it reaches the consumer at the end of the production line. There is a large proportion of the population that, in most cases unknowingly, consumes raw milk that has bacterial counts substantially higher than legal standards. Poor quality unpasteurized milk is either sold as fresh milk in the informal market, or as dairy products, such as cheese, manufactured from unpasteurized milk. Consumers are therefore, in most cases, unaware of the poor quality dairy products they consume. Milk quality is usually assessed in terms of bacterial content, which include Escherichia coli, coliforms and total bacterial count. The bacterial quality of milk is influenced by a number of factors, including farming practices, structural design of the milking shed, herd health and quality of water used in the dairy. If the highest level of hygiene practices is maintained, contamination of the milk by pathogenic microorganisms will be controlled, however, any drop in the vigilance of hygiene practices could result in unacceptable high levels of pathogenic microorganisms resulting in poor quality raw milk. Poor quality raw milk will inevitably result in poor quality pasteurized milk, containing unacceptably high levels of pathogenic organisms, which will eventually reach the consumer. Objectives The objectives of this study were to assess the quality of milk and influencing factors of milk produced on 83 dairy farms that supply milk intended for further processing to the greater Mangaung region, Central South Africa. Influencing factors investigated included, water quality and hygiene of milk contact surfaces, namely pulsator surfaces and milk pipeline surfaces. Methods Standard sampling procedures were followed when milk was sampled from bulk milk tanks, water at the point of use in the dairy, as well as collection of surface swabs. Escherichia coli, coliforms, total bacterial counts and somatic cell counts in milk were determined in terms of the regulations relating to milk and dairy products, and for water in terms of drinking water standards. These data were analysed and the factors that directly influence bacterial quality of milk were identified. Results 93% of the dairy farms displayed E. coli in their bulk milk containers, which did not comply with the legal standard. For coliforms, 86% of the milk samples did not comply with the legal standard. The total bacterial count of 85% of the milk samples did comply with the legal standard. The somatic cell count of 42% of the milk samples did not comply with the legal standard. The pulsator surfaces as well as the milk pipeline surfaces of 13% of the dairy farms displayed the presence of E. coli. 80% of the pulsator surfaces and 78% of the milk pipeline surfaces did comply with the legal standard pertaining to coliforms. The total bacterial count of pulsator surfaces revealed that 19% complied, whereas 29% of the milk pipeline surfaces complied with the legal standard. The water data further revealed that 31% of the dairy farms contained E. coli in the water used in the dairies. 63% of the dairy farms contained more than the allowable number of coliforms in their water. Chi-square tests revealed significant differences (p > 0.05) between the presence or absence of E. coli in milk and water; the presence or absence of E. coli in milk and milk pipeline surfaces; the presence or absence of E. coli in milk and pulsator surfaces and the presence or absence of E. coli in milk and the positioning of the cows in the milking shed. When milk quality indexes were calculated for all the farms, only four farms were classified with excellent milk, the remainder were all classified as producing poor quality milk. The hygiene quality indexes revealed that the hygiene practices on all the farms were not up to standard. Discussion and conclusion The study revealed that the milk produced for commercial processing and distribution in the greater Mangaung region of central South Africa was of poor quality. It is often mistakenly believed that the pasteurization process will remove all microorganisms from milk. As this is not the case, it is of major concern that milk delivered commercially is not of acceptable quality. Furthermore, it could be concluded that the quality of milk products from raw milk were also probably not of acceptable quality. The results further revealed that the possible contributing factors to the poor quality milk produced by the 83 commercial dairy farms were; poor quality water used in dairy sheds and contaminated milk contact surfaces. From this study it could be concluded that the overall status of milk production on the 83 commercial dairy farms studied, did not meet the standards required for milk quality, water quality and hygiene practices.
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Åkerlind, Maria. "Milk composition and metabolism of cows selected for high or low milk-fat concentration /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5702-5.pdf.
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Byrne, Robert Duane. "Assessment of dairy product quality by selective incubation and rapid techniques." Thesis, Virginia Tech, 1989. http://hdl.handle.net/10919/45943.
Full textAbstract:
A study was conducted to investigate the use of bacterial numbers and metabolites for their Value in predicting potential shelf-life of pasteurized fluid milk. The study consisted of two phases. In the first phase, chemical inhibitors were evaluated for their ability to allow growth of gram-negative psychrotrophic bacteria while inhibiting growth of gram-positive organisms. Crystal violet, benzalkonium chloride, a mixture of crystal violet and benzalkonium chloride, and alkylaryl sulfonate were tested. These were incubated with milk samples separately inoculated with gram-negative and gram-positive bacteria, at 2l°C for 18 hours. Alkylaryl sulfonate allowed growth of gram-positive organisms. Crystal violet inhibited gram-positive organisms but was not as effective as the mixture of crystal violet and benzalkonium chloride, The inhibitor of choice was benzalkonium chloride as it inhibited growth of all gram-positive organisms tested and allowed growth of the gram-negative psychrotrophic organisms.
Master of Science