Dissertations / Theses on the topic 'Beans – Drying'

An indirectly heated solar drier fitted with a flat plate collector and a directly heated solar drier were compared with open air sun drying of cocoa beans under field conditions in St. Lucia. Sun drying was conducted on two surfaces, perforated steel and non perforated wood. The methods were examined for the ability to adequately dry fermented beans and effect on quality. Loading rates of 13.5, 26.9 and 40.4 kg/m$ sp2$ were examined.
Temperature increases of 15$ sp circ$C and 20$ sp circ$C above ambient were achieved in the indirect and direct drier, respectively. The solar driers were more efficient than sun drying units at removing moisture throughout at loading rates of 26.9 and 40.4 kg/m$ sp2$ but only in the initial stages at 13.5 kg. External mould development was therefore reduced. Open air sun drying on the wooden surface proved more effective in the final stages at 13.5 kg/m$ sp2$.
The dried beans were of similar internal quality despite faster drying in the driers. The various drying methods and loading rates produced beans of similar pH while only loading rates affected titratable acidity differently. The direct solar drier achieved lower final moisture levels at high loads and was the cheaper alternative.

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

Orientadores: Barbara Janet Teruel Mederos, Claudio Kiyoshi Umezu
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola
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Resumo: A secagem de produtos agrícolas, especialmente grãos, é importante na pós-colheita, por ser responsável pelo prolongamento no seu tempo de armazenamento e conservação, resultado da redução da atividade de água presente em seu interior e conseqüentemente queda no desenvolvimento de micro organismos que conduziriam o produto a deterioração antecipada. Ao mesmo tempo em que a importância da realização de secagem é inquestionável, também é fato que este processo representa um consumo considerável de energia em virtude do aquecimento e movimentação forçada do ar que irá escoar por entre os grãos promovendo a retirada de massa de água (transferência simultânea de calor e massa). É importante que a temperatura do ar de secagem se mantenha no valor recomendado para não causar danos ao produto e não consumir mais energia que o necessário, este valor de temperatura varia de acordo com o produto e com sua finalidade de uso, neste trabalho considerou-se tal valor como sendo de 50 ºC. O objetivo deste trabalho foi desenvolver um sistema de secagem com capacidade de monitorar, registrar e atuar sobre o processo de secagem de maneira on line e proporcionar redução no consumo de energia e manutenção da qualidade do produto quando comparado com sistema operando com estratégia de controle on/off ou de forma automática com uso de um controlador de temperatura implementado através de software. O desenvolvimento do sistema de secagem constituiu-se de várias etapas: concepção, projeto e construção do secador, elaboração e montagem dos circuitos elétricos, instalação dos instrumentos de medição e sistema de aquisição de dados, desenvolvimento e implementação do aplicativo de monitoramento, registro e controle, após a calibração dos instrumentos foram realizados diversos testes livres para conhecer o comportamento do sistema, vários testes com diferentes condições de temperatura e vazão de ar foram necessários para avaliar o controlador, o que também implicou em testar controladores PID para temperatura implementados com diferentes algoritmos. Realizou-se os testes definitivos com o secador contendo cerca de 50kg de feijão e concluiu-se que houve redução no consumo de energia em torno de 18% e manutenção na qualidade do produto.
Abstract: Drying of agricultural products, especially grain is of fundamental importance in the stage of post-harvest, to be responsible for extending their time in storage and conservation, a result of reduced water activity in this consequently and drop them in the development of micro organisms that lead to product deterioration early. At the same time the importance of performing drying is unquestionable, it is also fact that this process represents a considerable consumption of energy due to heating and forced movement of air that will flow between the grains by promoting the removal of the water (simultaneous transfer of heat and mass). Found along the consultations related to the literature it is important to keep the temperature at which the grains are submitted within a limit that can promote or accelerate the removal of moisture without damaging the product, the recommended upper limit varies according in order to use the product, this work was considered as the temperature of 50 º C. The prime objective of this study was to develop a system capable of drying track, record and act on the drying process so online and provide reduction in energy consumption and maintenance of product quality when compared to how the on/off control strategy or automatically using a temperature controller implemented via software. The development drying system consisted of several stages: design, design and construction of the dryer, preparation and assembly of electric circuits, installation of measuring instruments and data acquisition system, development and implementation of application monitoring, recording and control, after the calibration of the instruments were performed several tests available to determine the behavior of the system, various tests with different conditions of temperature and flow rate of air were required to assess the controller, which also meant to test for PID temperature controllers with different structures. We carried out the final tests with the dryer containing about 50 kg of beans and concluded that there was a reduction in energy consumption around 18% and maintaining the quality of product.
Mestrado
Maquinas Agricolas
Mestre em Engenharia Agrícola

This thesis evaluates the effects of seed characteristics and environmental factors during and after maturation on hardseededness of wild beans (Phaseolus vulgaris L.). Accessions of wild beans from Durango and Tlaxcala in Mexico and 38 recombinant inbred lines from crossing wild and common beans were studied. Factors researched included temperature and water stress during seed maturation, drying temperature on and off the mother plant, seed size, testa colour and thickness of hilum and lens. The research traced the behaviour of individual wild bean seeds back to the seed positions in the pods in which they developed. Flowers of glasshouse-grown plants at Reading University were tagged individually and seed positions in the pods were recorded at every stage. Seeds of the accession Durango took longer to lose hardseededness (Le. were more . ~ hard seeded) at a maturation temperature of 25°C and when exposed to terminal water stress. In contrast, the tirhe to lose hardseededness diminished with a lower maturation temperature (l9°C) and terminal water stress. This can be explained by the higher seed moisture content of seeds grown at 19°C. If the seed closest to the point of attachment of the pod to the mother plant was hard, other seeds in the pod were also likely to be hard. Hardseededness increased with increase in number of seeds in each pod. Small seeds were also more likely to be hard seeded. Allowing seeds to dry naturally on the mother plant produced more hard seeds than harvesting early and drying the seeds off plant, even though the seeds dried off plant were at a lower moisture content. There was no evidence that the mechanism of hardseededness related to the thicknesses of hilum and lens. Results are discussed to show how hardseededness of wild beans could be used to maintain seed quality during storage.

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Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
Green bean is considered as one of most traditional Brazilian Northeast dishes. Green beans drying preliminary experiments show that combine processes, fixed-bed/spouted bed, resulted in dehydrated beans with uniform humidity and the recovery of the beans properties after their rehydration. From this assays was defined an initial humidity suited for the spouted bed process. A fixed-bed pre-drying process until a level of 40% humidity gave the best results. The spouted bed characteristic hydrodynamic curves were presented for different beans loads, where changes in the respective beans physical properties were evidenced during the fluidynamic assay, due simultaneous drying process. One 22 factorial experimental design was carried out with three repetition in the central point, considering as entry variables: drying air velocity and temperature. The response variables were the beans brakeage, water fraction evaporated during 20 and 50 minutes of drying and the humidity ratio. They are presented still the modeling of the drying of the green beans in fine layer in the drier of tray and the modeling of the shrinking of the beans of the drying processes fixed-bed and spouted bed
O feij?o verde ? considerado um dos pratos mais tradicionais do Nordeste. Experimentos preliminares de secagem do feij?o verde mostraram que o processo combinado, leito fixo/jorro favorecia a obten??o de gr?os desidratados com umidade uniforme e que ap?s reidrata??o o feij?o recuperava suas propriedades. A partir destes ensaios definiu-se uma umidade inicial adequada ao processamento no leito de jorro. A pr?-secagem em leito fixo at? um n?vel de umidade de 40%, forneceu os melhores resultados. S?o apresentadas as curvas hidrodin?micas caracter?sticas do leito para diferentes cargas de feij?o, onde se evidencia as respectivas mudan?as nas propriedades f?sicas dos gr?os ao longo do ensaio fluidodin?mico, decorrentes do processo simult?neo de secagem. Foi feito um planejamento experimental fatorial 22 com tr?s repeti??es no ponto central, considerando-se como vari?veis de entradas: a velocidade e temperatura do ar de secagem. As vari?veis respostas foram a quebra, a fra??o de ?gua evaporada nos 20 e 50 minutos de secagem, e a raz?o de umidade. S?o apresentados ainda a modelagem da secagem do feij?o verde em camada fina no secador de bandeja e a modelagem do encolhimento do feij?o ao longo dos processos de secagem em leito fixo e leito de jorro

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Currently an alternative that meets the demands of the modern consumer is the industrial processing. Due to the necessity of scientific materials about beans industrial processing in the national literature, then the objective in the first stage of this work (Paper 1) was prepare a review about this topic. Were presented some concepts and details of the industrial processing, unit operations and quality parameters evaluated in canned beans. In sequence (Paper 2) were presented the results of the study that evaluated the adaptability of eight bean cultivars for industrial processing. Cultivars evaluated were by commercial Carioca class: BRS Perola, BRS Estilo, BRS Ametista e BRS Notável and also the Black class: IPR Uirapuru, BRS Campeiro, BRS Esteio and BRS Esplendor. First the physical parameters of the grains were evaluated: water content, measurement of the size, roundness, weight of 100 seeds, density, bulk density, apparent moisture ratio and color components. Then the beans were processed at an industry of canning, using cans with a capacity of 420 g, in which the samples were put without the use of soaking. For sauce was used water at a temperature of 75°C and the cooking process and sterilization was performed in a rotary retort. The quality parameters were evaluated in canned beans: total, net and drained weight, headspace, damage index, color, soluble solids and total solids in the sauce, texture, acidity and pH. Data were submitted to multivariate analysis: Principal Components and Hierarchical Clustering. As a result it was found that the Carioca class BRS Estilo differs from others due to low drained weight that contributed to the increase of total solids in the broth, with low hardness values, not adapting to the type of process used in this experiment. In Black class were observed similar quality characteristics between cultivars BRS Esplendor and IPR Uirapuru, and between BRS Campeiro and BRS Esteio, especially this last one by having smaller index of damaged grains after processing. Lastly, in the last work (Paper 3) was presented information about a different option of product by beans, the quick cooking dehydrated, pointing details of the processing and the performance of Brazilian bean varieties, as well as the technological quality of the final product. In the processing of quick-cooking dried beans was used a Central Composite Design (CCD) with two factors. The first factor was cultivar, evaluating BRS Pérola, BRS Madrepérola, BRS Estilo and IAPAR 81. The second factor was concentration of NaHCO3 used in soaking operation followed by drying of the beans. Were evaluated the parameters: cooking time, damage index and color difference in the processed product. It was found that the effects on these quality parameters are dependent upon the cultivar factor, because BRS Estilo and BRS Madrepérola stood out due to reduced cooking time and color difference when compared to BRS Pérola and IAPAR 81. For BRS Estilo cultivar the increased of NaHCO3 concentration in the soaking reduced significantly the cooking time, with lower rates of damage when compared to BRS Madrepérola. Finally, the information in this work intends to contribute with future research on this topic and therefore increase the bean consumption, whether in the form of an innovative product like the quick cooking dehydrated or as canned beans.
Atualmente uma alternativa alimentar que atende às demandas do consumidor moderno é o processamento industrial do feijão. Devido à necessidade de materiais científicos sobre processamento industrial do feijão na literatura nacional, objetivou-se na primeira etapa deste trabalho (Artigo 1) elaborar uma revisão de literatura sobre o tema. São apresentados alguns conceitos e detalhes do processamento industrial, das operações unitárias e dos parâmetros de qualidade avaliados no feijão enlatado. Na sequência (Artigo 2), apresentam-se os resultados do trabalho que avaliou a adaptabilidade de oito cultivares de feijão ao processamento industrial. Foram avaliados cultivares da classe comercial Carioca: BRS Pérola, BRS Estilo, BRS Ametista e BRS Notável; da classe Preto: IPR Uirapuru, BRS Campeiro, BRS Esteio e BRS Esplendor. Primeiramente, foram verificados os parâmetros físicos nos grãos: teor de água, aferição das dimensões, esfericidade, massa de 100 grãos, densidade, massa específica aparente, coeficiente de hidratação e componentes de cor. Em seguida, os grãos foram processados em uma indústria do setor, utilizando-se embalagens metálicas com capacidade de 420 g, nas quais as amostras foram acondicionadas sem o emprego de hidratação prévia. Como calda, utilizou-se água na temperatura de 75 °C e o processo de cozimento e esterilização foi realizado em autoclave rotativa. No feijão enlatado, avaliaram-se os parâmetros de qualidade: peso bruto, líquido e drenado, altura de headspace, índice de danos, cor, sólidos solúveis e sólidos totais no caldo, textura, acidez e pH. Os dados foram submetidos à análise multivariada: componentes principais e de agrupamento. Como resultado, verificou-se que, na classe Carioca, o cultivar BRS Estilo diferencia-se dos demais, devido ao baixo peso drenado que contribuiu para o aumento de sólidos totais no caldo, com baixos valores de dureza, não se adaptando ao tipo de processo utilizado neste experimento. Na classe Preto, observaram-se características de qualidade semelhantes entre BRS Esplendor e IPR Uirapuru, e entre BRS Esteio e BRS Campeiro, destacando-se esta última por apresentar menores índices de grãos danificados após o processamento. Por fim, no último trabalho (Artigo 3), apresentam-se informações sobre uma opção diferenciada de produto derivado do feijão, o desidratado de cozimento rápido, apontando-se detalhes sobre o processamento e a performance de diferentes cultivares brasileiros, assim como a qualidade tecnológica. No processamento do feijão desidratado de cozimento rápido foi empregado um delineamento composto central (DCC) com dois fatores. O primeiro fator foi cultivar, avaliando-se BRS Pérola, BRS Madrepérola, BRS Estilo e IAPAR 81; o segundo fator foi a concentração de NaHCO3 (bicarbonato de sódio) empregado na hidratação, seguida da secagem dos grãos. Foram avaliados os parâmetros tempo de cozimento, índice de dano e diferença de cor no produto processado. Verificou-se que os efeitos nos parâmetros de qualidade são dependentes do fator cultivar, visto que BRS Estilo e BRS Madrepérola destacaram-se devido ao menor tempo de cozimento e diferença de cor, quando comparados ao BRS Pérola e IAPAR 81. Para BRS Estilo, o aumento na concentração de NaHCO3 reduz significativamente o tempo de cozimento, com menor índice de dano quando comparado ao cultivar BRS Madrepérola. Por fim, com as informações presentes neste trabalho pretende-se contribuir com pesquisas futuras sobre o tema e dessa forma incrementar o consumo do feijão, seja na forma de um produto inovador como o desidratado de cozimento rápido ou na forma de enlatado.

This study is aimed to compare the fluidized bed and microwave drying with microwave assisted fluidized bed drying. For this purpose, macaroni beads (2.4±
0.08 mm diameter) were dried from about 20% to 12% moisture content in a fluidized bed of 7.6 cm diameter, in a domestic microwave oven with a power of 609 W and in the fluidized bed placed in the microwave oven conditions. In the experiments with the fluidized bed three air temperatures
50, 60 and 70°
C at an air velocity of 2.3 m/s and in those with the microwave oven two power levels
50% and 100% were used. The drying curves indicated that the drying rate increased with the air temperature and microwave power in each drying method. Microwave assisted fluidized bed drying reduced the drying time by about 50% and 11% on the average compared with the fluidized bed and microwave drying, respectively. Therefore, it was concluded that the drying time was reduced more by the effect of microwave energy than the fluidization. The effective diffusivities in the fluidized bed and microwave assisted fluidized bed drying were found to be in the order of 4.125x10-11 and 8.772x10-11 m2/s on the average, respectively. The effective diffusivities for the fluidized bed drying were fitted to an Arrhenius type of equation and the magnitude of the activation energy was found to be in the order of 12595 kJ/kg mol.

L’objectif général de cette thèse a été d’étudier le potentiel de billes à base de molécules d’α-cyclodextrine et d’huile de soja, pour l’administration orale de principes actifs peu solubles dans l’eau.Nous avons tout d’abord vérifié qu’il était possible d’encapsuler dans les billes des molécules actives (la progestérone et l’indométacine) autres que les rétinoïdes et le diazépam, avec une teneur élevée et un rendement de fabrication satisfaisant. L’étude du comportement des billes nues lyophilisées, en termes de stabilité et de libération dans des milieux digestifs simulés, nous a permis de proposer un mécanisme de libération de la molécule encapsulée qui se déroule en plusieurs étapes: i) hydratation des billes, ii) dissolution de la matrice hydrophile d’α-cyclodextrine, iii) libération de gouttelettes d’huile contenant le principe actif puis de la fraction dissoute dans l’huile par un phénomène de partage, iiii) fragmentation des billes fragilisées et libération totale de l’huile. La présence de sels biliaires dans le milieu, accélère à la fois la libération et la quantité dissoute, en fragilisant les billes et en réduisant la valeur du coefficient de partage du principe actif entre l’huile et le milieu digestif. Nous avons montré in vitro et in vivo qu’il est possible de moduler la libération d’un principe actif à partir d’une même formulation de départ, en jouant sur l’organisation du système (émulsion sèche, billes nues, billes coquées par un nouvel ajout d’α-cyclodextrine sur les billes nues). Les études in vivo chez le rat ont révélé que l’émulsion sèche se comporte comme une forme à libération immédiate, les billes coquées comme une forme à libération prolongée et les billes nues comme une forme à libération intermédiaire. Enfin, la libération du principe actif encapsulé peut également être modulée en modifiant le mode de séchage des billes. Comparativement à la lyophilisation, le séchage à l’étuve modifie les propriétés des billes en augmentant leur résistance dans les milieux digestifs simulés et prolonge la libération de la molécule encapsulée
The general aim of this thesis was the study of the potential of beads, made of α-cyclodextrin and soybean oil, for the oral delivery of poorly water soluble drugs. We have first verified that it was possible to encapsulate in beads, active molecules (progesterone and indomethacin), other than retinoid and diazepam, with a high drug loading and a satisfying yied. The study of the behaviour of freeze-dried naked beads, in terms of stability and drug release in simulated gastro-intestinal fluids, allowed to propose a mechanism for the release of the encapsulated drug, involving several steps: i) hydration of the freeze-dried beads, ii) dissolution of α-CD hydrophilic matrix, iii) release of oily droplets containing the active drug and then of the fraction of drug dissolved in oil, following a partition phenomenon, iiii) fragmentation of the weakened beads and at last the total release of oil. The presence of bile salts in the medium accelerates both the release and the dissolved amount, by weakening the beads and reducing the partition coefficient value of the active molecule between oil and digestive medium.We have shown in vitro as well as in vivo that it is possible to modulate the release of a model drug from the same initial formulation, according to the degree of organization of the system (dry emulsion, naked beads, coated beads obtained by an additional amount of α-cyclodextrine to the preformed naked beads). In vivo studies in rats have highlighted that dry emulsion behaves as a fast release formulation, the coated beads as a sustained release formulation and the naked beads as an intermediate one. Finally, the release of the encapsulated drug can also be modulated by modifying the drying method of the beads. Compared to freeze-drying, oven-drying modifies the properties of the beads by increasing their resistance in simulated gastro-intestinal fluids and sustaining the release of the encapsulated drug

On envisage deux types de configuration du systeme de sechage suivant la nature du generateur d'air chaud. Dans la premiere configuration, le sechoir est ventile par de l'air chaud sortant d'un capteur solaire du type multi-masse. La seconde configuration utilise un rechauffeur d'air constitue de resistances electriques. Pour chaque sous-systeme de la chaine, on propose une modelisation fine et originale; une etude systematique de l'etat thermique, massique et des performances du systeme de captation multi-passes et du systeme de sechage en fonction des parametres externes et internes est realisee. On envisage aussi l'effet d'un recyclage de l'air sur le comportement dynamique du systeme de sechage. Enfin, une conformation entre les resultats experimentaux obtenus sur un prototype construit et teste en laboratoire avec des resistances electriques permet une validation du modele theorique propose pour le sechage d'un lit epais des feves de cacao

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Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
The green bean has organoleptic and nutritional characteristics that make it an important food source in tropical regions such as the Northeast of Brazil. It is a cheap source of protein and important for nutrition of rural population contributing significantly in subsistence farming of the families from Brazil s northeast. It is consumed in entire region and together with the dry meat and other products composes the menu of typical restaurants, being characterized as an important product for economy of Northeast. The green bean is consumed freshly harvested and has short cycle, being characterized as a very perishable food, which hampers your market. The drying method is an alternative to increase the lifetime and provide a reduction volume of this product making easier your transportation and storage. However is necessary to search ways of drying which keep the product quality not only from the nutritional standpoint but also organoleptic. Some characteristics may change with the drying process such as the coloring, the rehydration capacity and the grains cooking time. The decrease of drying time or of exposure of the grains to high temperature minimizes the effects related with the product quality loss. Among the techniques used to reduce the drying time and improve some characteristics of the product, stands out the osmotic dehydration, widely used in combined processes such as the pretreatment in drying food. Currently the use of the microwaves has been considered an alternative for drying food. The microwave energy generates heat inside of materials processed and the heating is practically instantaneous, resulting in shorter processing times and product quality higher to that obtained by conventional methods. Considering the importance of the green beans for the Northeast region, the wastefulness of production due to seasonality of the crop and your high perishability, the proposal of this thesis is the study of drying grain by microwaves with and without osmotic pretreatment, focusing on the search of conditions of processes which favor the rehydration of the product preserving your organoleptic characteristics. Based on the analysis of the results of osmotic dehydration and dielectric properties was defined the operating condition to be used in pretreatment of the green bean, with osmotic concentration in saline solution containing 12,5% of sodium chloride, at 40?C for 20 minutes. The drying of green bean by microwave was performed with and without osmotic pretreatment on the optimized condition. The osmotic predehydration favored the additional drying, reducing the process time. The rehydration of dehydrated green bean with and without osmotic pretreatment was accomplished in different temperature conditions and immersion time according to a factorial design 22, with 3 repetitions at the central point. According to results the better condition was obtained with the osmotically pretreated bean and rehydrated at a temperature of 60?C for 90 minutes. Sensory analysis was performed comparing the sample of the green bean in natura and rehydrated in optimized conditions, with and without osmotic pretreatment. All samples showed a good acceptance rate regarding the analyzed attributes (appearance, texture, color, odor and taste), with all values above 70%. Is possible conclude that the drying of green bean by microwave with osmotic pretreatment is feasible both in respect to technical aspects and rehydration rates and sensory quality of the product
O feij?o verde apresenta caracter?sticas organol?pticas e nutricionais que fazem dele uma importante fonte aliment?cia em regi?es de clima tropical como o Nordeste do Brasil. ? uma fonte de prote?na barata e importante para a nutri??o da popula??o rural contribuindo significativamente na agricultura de subsist?ncia das fam?lias nordestinas. ? consumido em toda a regi?o e comp?e junto com a carne de sol e outros produtos o card?pio dos restaurantes t?picos, caracterizando-se assim como um produto importante para a economia da Nordeste. O feij?o verde ? consumido rec?m-colhido e apresenta ciclo curto, sendo caracterizado como um alimento de alta perecibilidade, o que dificulta a sua comercializa??o. A secagem desse produto se caracteriza como uma alternativa para o aumento da vida ?til deste alimento, al?m de proporcionar uma redu??o de volume facilitando seu manuseio no transporte e armazenagem. Todavia necess?rio se faz buscar formas de secagem que preservem a qualidade do produto n?o s? sobre o ponto de vista nutricional como organol?ptico. Dentre as caracter?sticas que se alteram com o processo de secagem, destacam-se a colora??o, a capacidade de reidrata??o e o tempo de cozimento dos gr?os. A diminui??o do tempo de secagem, ou de exposi??o dos gr?os a elevadas temperaturas minimizam os efeitos relacionados com a perda de qualidade do produto. .Dentre as t?cnicas empregadas para minimizar o tempo de secagem e melhorar algumas caracter?sticas do produto, destaca-se a desidrata??o osm?tica, muito utilizada em processos combinados como pr?-tratamento na secagem dos alimentos. Atualmente a utiliza??o do micro-ondas tem sido apontada como uma alternativa para a secagem de alimentos. A energia de micro-ondas gera calor no interior dos materiais processados e o aquecimento ? praticamente instant?neo, o que resulta em tempos de processamento mais curtos e qualidade do produto superior ? obtida pelos m?todos convencionais. Considerando a import?ncia do feij?o verde para a regi?o Nordeste, o desperd?cio da produ??o devido a sazonalidade da safra e sua alta perecibilidade, foi proposto nesta tese o estudo da secagem dos gr?os em micro-ondas com e sem pr?-tratamento osm?tico, tendo como foco principal a busca das condi??es de processo que favore?am a reidrata??o do produto, com preserva??o de suas caracter?sticas organol?pticas. A partir da an?lise dos resultados da desidrata??o osm?tica e propriedades diel?tricas foi definida a condi??o operacional a ser utilizada no pr?-tratamento do feij?o verde, com concentra??o osm?tica em solu??o salina contendo 12,5% de cloreto de s?dio, a 400C por 20 minutos. A secagem do feij?o verde por micro-ondas foi realizada sem e com pr?-tratamento osm?tico na condi??o otimizada. A pr?-desidrata??o osm?tica favoreceu a secagem complementar, reduzindo o tempo de processo. A reidrata??o do feij?o verde desidratado com e sem pr?-tratamento osm?tico foi realizada em diferentes condi??es de temperatura e tempo de imers?o de acordo com um planejamento fatorial 22, com 3 repeti??es no ponto central . De acordo com os resultados a melhor condi??o, foi obtida com o feij?o pr?-tratado osmoticamente e reidratado a uma temperatura de 600C por 90 minutos. Realizou-se a an?lise sensorial comparando-se as amostra de feij?o verde in natura e reidratado nas condi??es otimizadas, com e sem pr?-tratamento osm?tico. Todas as amostras apresentaram um bom ?ndice de aceita??o referente aos atributos analisados (apar?ncia, textura, cor, odor e sabor), estando todos os valores acima de 70%. Conclui-se que a secagem do feij?o verde por micro-ondas com pr?-tratamento osm?tico ? vi?vel, tanto em rela??o aos aspectos t?cnicos como aos ?ndices de reidrata??o e a qualidade sensorial do produto

Die vorliegende Arbeit beschäftigt sich mit der Herstellung von funktionellen Magnetit-Nanokompositen durch Sprühtrocknung für die Anwendung in der Bioseparation. Dabei liegen die Schwerpunkte auf der Anwendung von Polyelektrolyten als Ionenaustauscher sowie auf der Nachhaltigkeit des Herstellungsprozesses. Basierend auf einem existierenden Herstellungsprozess wurde die Aufgabenstellung konkretisiert. Es wurden Möglichkeiten zur nachhaltigen Prozessgestaltung der Synthese von kationischen bzw. anionischen magnetischen Funktionspartikeln zur Proteinabtrennung vorgestellt. Als magnetische Komponente wurde Magnetit verwendet. Aufgrund seines pseudo-amphiphilen Charakters und seiner besonderen Eigenschaften in Bezug auf die Stabilisierung von Magnetit-Kolloiden wurde Polyvinylbutyral (Mowital B 30T) als Matrixpolymer bei der Sprühtrocknung benutzt. Für die nachhaltige Prozessgestaltung wurden Isopropanol und Tetrahydrofuran als Dichlormethan-Ersatz bei der Sprühtrocknung verwendet. Bei der Synthese kationischer Magnetic Beads wurden verzweigtes Polyethylenimin und lineares Poly(Allyamin) als Anionenaustauscher verwendet. Beide Polykationen sind schwache Polyelektrolyte mit Aminogruppen. Für die Verarbeitung der Polykationen als funktionelle Liganden in magnetischen Funktionspartikeln wurde zwei Herstellungsmethoden vorgestellt: eine Synthese ohne Oberflächenmodifizierung, wobei die mechanische und chemische Stabilität der Funktionspartikeln einzig von der chemischen Struktur der eingesetzten Materialien bzw. vom Matrixpolymer abhängt, und eine Synthese mit Oberflächenmodifizierung. Die Synthese mit Oberflächenmodifizierung ist gekennzeichnet durch die kovalente Bindung von Polyethylenimin bzw. Poly(Allyamin) an der Oberfläche der Funktionspartikeln (Polyvinylbutyral). Dafür wurde 1,1’-Carbonyldiimidazol als „zero length“-Crosslinker benutzt. Die nach beiden Methoden hergestellten Funktionspartikeln wurden charakterisiert, um ihre technische Eignung beurteilen zu können. Für die Charakterisierung der sorptiven Eigenschaften wurde unter anderem der Bowman-Birk Inhibitor (BBI) verwendet. Das Protein ist ein Sojaprodukt und für seine krebsvorbeugende Wirkung bekannt. Um die Selektivität der Abtrennung zu untersuchen, wurden BBI-Produkte mit unterschiedlichen Reinheitsgraden benutzt. Durch die zwei vorgestellten Methoden konnten kationische magnetische Funktionspartikeln erfolgreich hergestellt werden. Alle Funktionspartikeln sind superparamagnetisch, und der Medianwert ihrer Partikelgrößenverteilung liegt im einstelligen Mikrometerbereich. Aufgrund eines höheren Polykationanteils ist die Bindungskapazität der Funktionspartikeln ohne Oberflächenmodifizierung um den Faktor 2,4 größer als die BBI-Bindungskapazität der Funktionspartikeln mit Oberflächenmodifizierung (Qmax=322 mg/g). Das Fehlen eine feste Anbindung des funktionellen Liganden an den Funktionspartikeln ohne Oberflächenmodifizierung verleiht jedoch diesen eine sehr schlechte chemische Stabilität in Lösungen. Es wurde auch gezeigt, dass oberflächenmodifizierte Funktionspartikeln mit ähnlichen Eigenschaften durch den Einsatz von Dichlormethan bzw. Tetrahydrofuran als Lösungsmittelersatz während der Sprühtrocknung hergestellt werden können. Durch den Einsatz von mit Poly(allylamin) oberflächenmodifizierten Funktionspartikeln konnte BBI von technischen Sojamolken unterschiedlicher Reinheitsgrade erfolgreich abgetrennt werden. Anionische Magnetic Beads wurden mit Kationenaustauscherharz als funktionellem Ligand hergestellt. Dabei wurde Isopropanol als organisches Lösungsmittel während der Sprühtrocknung verwendet. Die Synthese wurde analog zur Synthese der kationischen Magnetic Beads ohne Oberflächenmodifizierung durchgeführt. Es wurde auch hier gezeigt, dass anionische magnetische Funktionspartikeln mit guten sorptiven Eigenschaften durch den Einsatz von Isopropanol als organisches Lösungsmittel hergestellt werden können. Die anionischen Funktionspartikeln besitzen im Vergleich zu Literaturwerten höhere Bindungskapazitäten (bis 280 mg/g; ermittelt mit Lysozym). Im letzten Kapitel wird der kritische Prozessschritt des Lösungsmittelaustausches behandelt. Nach dem Lösungsmittelaustausch sollten die Magnetitnanopartikeln in der organischen Phase stabil sein. Dies ermöglicht sowohl eine homogene Verteilung der Nanopartikeln in der Matrix als auch deren bessere Verkapselung während der Sprühtrocknung. Es wurde festgestellt, dass sich eine vollständige Abtrennung von Dichlormethan durch die angewendete Destillationsmethode nicht erreichen lässt. Anhand von zwei Modellsystemen — Rizinolsäure- und Ölsäure-beschichteten Magnetitnanopartikeln — und Lösungsmittelgemischen wurde die Stabilität von sterisch stabilisierten Magnetitpartikeln in binären Lösungsmittelgemischen untersucht. Der Fokus bei dieser Untersuchung lag auf der Untersuchung der Stabilität der beschichteten Magnetitnanopartikeln in einer möglichst Dichlormethan- bzw. Isooktan-freien organischen Phase. Als zweites Lösungsmittel (als Lösungsmittelersatz betrachtet) wurden neben Tetrahydrofuran und Isopropanol technisch verbreitete Lösungsmittel wie Isooktan und 1-Butanol eingesetzt. Die Untersuchungsergebnisse zeigen, dass die Anwendung der technischen Rizinolsäure bzw. Ölsäure einen zusätzlichen Einfluss auf die Stabilität der Magnetitpartikeln hat, da diese aus anderen Fettsäuren mit unterschiedlichen chemischen Strukturen bestehen. Die Diskrepanz zwischen der berechneten HANSEN-Distanzen und der Stabilität der Magnetitnanopartikeln mit reinen Fettsäuren lässt vermutet, dass die Zusammensetzung der Lösungsmittelgemische an der fest/flüssig-Grenzfläche anders ist als im freien Volumen. Ein Modell zur Beschreibung der Stabilität der Nanopartikeln, das auf einer Anreicherung des Ausgangslösungsmittels an der Grenzfläche basiert, wurde postuliert. Solange die Diffusion des zweiten Lösungsmittels in die Adsorptionsschicht nicht ausreichend genug ist, um die Löslichkeit der Fettsäureketten entscheidend zu reduzieren und somit einen Abfall der Abstoßungskräfte zwischen der Partikeln hervorzurufen, bleiben alle beschichteten Magnetitnanopartikeln stabil im Lösungsmittelgemisch. Dies ist der Fall für die mit der reinen Rizinolsäure beschichteten Magnetitnanopartikeln in allen verwendeten Lösungsmittelgemischen mit 0,5 Vol. % DCM in der kontinuierlichen Phase. Durch die vorgestellten Herstellungsmethoden wurde gezeigt, dass magnetische Funktionspartikeln sowohl mit festen partikelförmigen Ionenaustauschern als auch mit flüssigen schwachen Polyelektrolyten erfolgreich synthetisiert werden können. Eine nachhaltige Prozessgestaltung durch die Reduzierung der Dichlormethanmenge im Sprühtrocknungsprozess ist auch möglich. Für eine erfolgreiche industrielle Anwendung der Funktionspartikeln müssen aber ihre chemischen sowie mechanischen Eigenschaften deutlich verbessert werden. Dies könnte z.B. durch die Verwendung eines anderen Matrixpolymers oder durch die Entfernung von nicht gebundenen Bestandteilen durch gezielte Waschung der Funktionspartikeln erfolgen. Die Bindungskapazität sowie die Selektivität der oberflächenmodifizierten Funktionspartikeln sollte ebenfalls verbessert werden. Dafür wurde einen Ansatz durch die Quaternisierung der Aminogruppen präsentiert. Schließlich würde die Untersuchung der Stabilität der beschichteten Magnetitnanopartikeln in einphasigen reinen Lösungsmitteln nähere Erkenntnisse über das postulierte Modell der Anreicherung von Dichlormethan in der Adsorptionsschicht erbringen. Dabei könnte die Dichlormethanmenge durch mehrstufige Destillation bzw. Rektifikation beim Lösungsmittelaustausch entfernt werden. Eine vollständige Untersuchung dieses Effekts würde zusätzlich eine Antwort auf zahlreiche Fragestellungen der Kolloidchemie in Bezug auf das Stabilitätsverhalten von Pigmentdispersionen (Lacke) oder von beschichteten Nanopartikeln in Polymerlösungen erbringen.

La présente thèse traite, au travers d’une analyse fondamentale et expérimentale, l’effet de texturation par détente instantanée contrôlée (DIC) sur les phénomènes de transfert au cours des processus de séchage, d’extraction mécanique et de comportement rhéologique. Les produits concernés ont été les graines de caroube (gomme et germe) et deux variétés de graines de tournesol (linoléique et oléique). La texturation DIC permet d’agir sur la cinétique de séchage par flux d’air ce qui conduit à une intensification des processus de séchage par flux d’air tout en assurant une bonne préservation de la qualité nutritionnelle du produit fini. L’étude expérimentale a été couplée à une analyse phénoménologique de la cinétique à travers une modélisation de type CWD (coupled Washing/Diffusion). Cette dernière étude conduit à une évaluation de l’impact de la texturation sur la diffusivité effective Deff et l’accessibilité initiale δWs. D’autre part, l’étude expérimentale en vue de l’optimisation de l’opération a été réalisée à travers la méthode des plans d’expériences. La modification des paramètres opératoires fonctionnels de la DIC, à savoir la pression absolue de vapeur d’eau saturée sèche (P), et le temps de traitement thermique (t), ainsi que le nombre des cycles (c) sur l’ensemble des performances de l’opération a été établie sur le comportement rhéologique de la gomme de caroube. Une deuxième partie de la thèse a été consacrée à l’étude fondamentale et expérimentale des procédés d’extraction d’huile de tournesol des deux variétés de graines linoléiques et oléiques. Le traitement thermomécanique par détente instantanée contrôlée (DIC) permet, à travers une modification contrôlée de la structure de la matière première, d’agir sur l’extraction mécanique par presse à froid des huiles de tournesol, ainsi que sur l’extraction par solvant de l’huile à partir du tourteau résiduel. Un complément à cette opération a consisté en l’extraction par solvant (n-hexane) opérée sur l’ensemble des graines de tournesol. La texturation DIC a conduit à une grande augmentation du rendement en huile pour les variétés linoléique et oléique. La préservation de la qualité de l’huile et du tourteau prouve l’adéquation de la DIC avec l’absence pratique de la dégradation chimique. Notre étude a également concerné la définition d’un nouveau procédé de désodorisation. Il s’agit de l’utilisation de l’Autovaporisation Multi-Flash MFA sur le raffinage de l’huile de tournesol. Cette technologie innovante de désodorisation se distingue par son faible niveau de température assurant ainsi une sévérité nettement inférieure à celle des méthodes conventionnelles à haute température
This thesis deals with a fundamental and experimental analysis of the effect of instant controlled pressure drop (DIC) on the transfer phenomena and rheological behavior, which occurs during the drying process and mechanical and solvent extraction. The products concerned were carob seeds (gum and germ) and two varieties of sunflower seeds (linoleic and oleic). DIC texturing makes it possible to greatly modify the drying kinetics, leading to an effective intensification of the drying processes while maintaining a good preservation of the nutritional quality of the finished product. The experimental study was coupled with a phenomenological kinetic model using the CWD (coupled Washing/Diffusion). This study leads to evaluate the impact of texturing on the effective diffusivity Deff and the initial accessibility δWs. On the other hand, the experimental study for the optimization of the operation was carried out through an adequate experimental design method. The impact of the DIC processing parameters, namely the absolute pressure of saturated dry water vapor (P), and the heat treatment time (t), as well as the number of cycles (c) was established on the rheological behavior of the carob bean gum. A second part of our work was devoted to the theoretical and experimental study of sunflower oil extraction processes of the two types of linoleic and oleic seeds. By acting as a controlled modification of the raw material, (DIC) texturing allowed increasing the yield of sunflower oil by both cold pressing and solvent extraction from the residual cake. DIC texturing has led to a large increase in oil yield for both linoleic and oleic varieties. The preservation of the quality of oil demonstrates that DIC was perfectly adequate with a perfect absence of chemical degradation. Our study also involved the definition of a new deodorization process. This is the use of the Multi-Flash Autovaporization MFA on the refining of sunflower oil. This innovative deodorization technology is characterized by its low temperature level, thus ensuring a much lower severity than conventional high temperature methods

碩士
國立中興大學
園藝學系所
103
In order to maintain the vitality of seeds during storage, seeds need to be dried to the critical moisture content before storage. As a new desiccant drying technology, seed drying beads are modified ceramic materials (aluminum silicates or zeolites) that can absorb and hold water molecules very tightly in their microscopic pores. The beads continue to absorb water until all of their pores are filled, and can be regenerated for repeated use. When seeds are placed in a seal container with the drying beads, the beads remove water from the air, creating and maintaining a very low humidity environment. This leads to the seedsimmediately losing water due to absorbance by the drying beads until they come to a state of equilibrium. This study, examined the effects of this new drying technique on the germination rate and physiological activity of harvested sweet pepper ''Blue Star'' and cucumber ''Wanji'' seeds. It aimed to establish the optimal condition for the seeds with respect to the drying beads ratio and temperature during the drying process for sweet pepper and cucumber seeds. The moisture content of all three particle sizes of drying beads tested increased by more than 6% after 2 hours of absorbance in a 100% relative humidity environment. The particle size and ambient temperature affected the initial water absorption capacity of the drying beads. Large and small drying beads had good water absorption capacities in the early stage of drying at 15℃ and 25℃. In addition, the particle size and temperature gad no significant effects on the moisture content of the drying beads at three different temperatures after 72 hours of drying. For sweet pepper seeds, small drying beads of 3 and 5 times the weight of the seed were used and their effects on the seed vigor after drying at 25℃ were examined. With drying beads 3 times the weight of the seed, mean germination day, mean emergence day were decreased and the physiological activities, such as electrical conductance and MDA content, were significantly increased. The respiration rate and CAT activity of the seeds dried with drying beads that were 3 times the seed weight were also greater than those of the seed dried using beads that were 5 times the seed weight. For seeds that underwent accelerated aging treatment, the drying beads that were 3 times the seed weight reduced the seed moisture content from 43% to 10% within 18 hours at 25℃, and the seed respiration the ratio of dtying beads reduced the drying time, while with the drying beads of 5times the seed weight, the seed electrical conductance increase. After 6 months of storage, the seed electrical conductance decreased and the germination percentage was over 85.6% for seeds dried with drying beads of 3 times the seed weight at 25℃. For cucumber seeds, large drying beads of 3 and 5 times the seed weight were used and their effects on the seed characteristics after drying were examined. Drying beads of both sizes reduced the seed moisture content from 33% to 10% within 2 hours and had no significant impacts on the seed vigor or seed physiological activity. For seeds that underwent accelerated aging treatment, different ratios of drying beads to seeds had no significant correlation with seed vigor, but the drying temperature significantly affected the germination rate and physiological activity. With drying beads 3 times the seed weight, the seed germination percentage increased to 91% under drying at 25℃. Increasing the amount of drying beads to 5 times the seed weight reduced the drying time ny one hour, and had no significant impacts on the seed vigor but decreased the seed respiration rate. In addition, after 6 months of storage, the mean germination duration was shorter and the germination percentage was maintained at greater than 85% for seed dried with drying beads 5 times the weight of the seed at 25℃.

碩士
輔仁大學
食品科學系碩士班
106
Tofu is a widely accepted soy product in East Asia. However, the procedure of tofu making is complicated and consumes a lot of energy. Moreover, the okra which contains high amount of protein and dietary fiber is discarded as waste. The objectives of this study were to investigate the physicochemical property of whole bean tofu prepared with micronized soy paste and deep sea water (DSW); and to study the effect of different drying methods on the physicochemical property of soy flour and the property of whole bean tofu prepared with the treated flour. Soybeans were wet-micronized by using the food processor and mixed with soy protein isolate. The paste was then heated at 95℃ for 10 min and the thermal-treated soy paste (TSP) was produced. The TSP was further dried by using drum dryer at 130℃ and cold-air dryer at 40℃ to produce the thermal-treated soy flour (TSF). Both TSP and TSF were used to prepare the paste with the concentration of 10% and 15% for tofu making. Glucono delta-lactone (GDL) and DSW were used as coagulant. The gelation behavior and physicochemical property of whole bean tofu were evaluated. Results showed that the phase transition of 10% TSP with GDL addition was observed during gelation by using rheometer. However, the elastic modulus was higher than the viscous modulus in the initial stage of gelation of the other groups, and the gelation point was not as easy to observe. Whole bean tofu prepared with TSP and TSF had high amount of protein and fiber. The tofu prepared with 10% TSP and GDL showed the smooth and uniform appearance, and the firmness texture, and the regular honeycomb-like structure. The appearance of whole bean tofu prepared with TSP and DSW was slightly rough and its texture was soft. The TSF prepared by using drum dryer was less time consuming. The tofu prepared with TSF and GDL or DSW showed a curd-like appearance with obvious phase separation and soft texture. According to the above results, the fibers in the paste of TSP and TSF might alter the gelation behavior and further change the protein network structure of tofu, and consequently, produce the tofu with unique texture. This research provides an innovative approach for whole bean tofu making at home by using household utensils without waste generation.