Previous research has shown that microsomal DGAT activity from cultures of Brassica napus was stimulated by human acylation stimulating protein (ASP) and bovine serum albumin (BSA). Genetic constructs were engineered to facilitate the expression of ASP or BSA in developing seeds to test the stimulatory effect of these proteins at the site of TAG formation. As well, genetic constructs were designed to produce a truncation of the BSA polypeptide in an attempt to localize the portion fo the macromolecule responsible for stimulation of DGAT activity. An oleosin promoter was used for seed specific expression and to express the polypeptides at a precisely cooridnated time when oil was accumulating in the developing seeds. Lipid analysis coordinated time when oil was accumlating in the developing seeds. Lipid analysis was performed on the seeds of transgenic plants designed to cytosolically express these mammalian proteins and the seeds of control plants. The first generation data revealed that the total lipid within the mature seeds of ASP and BSA plants was not significantly different from the total lipid of negative control plants using both gravimetric and low resolution-nuclear magnetic resonance methods of analysis. The seeds from ASP 8 and ASP 10 plants, however, did produce significantly more lipid on a per seed basis as compared to negative control plants. The levels of the fatty acid composition for total acyl lipids were measured in these first generation transgenic plants. ASP 3 had significantly lower levels of linoleic acid, ASP 14 had significantly lower levels of a-linolenic acid and BSA 11 had significantly higher levels of both of these fatty acids in comparison to negative control plants. / xix, 245 leaves : ill. ; 28 cm.

No description available.

The commercial pressure frying has been limited to frying huge amount of products due to its dependence on the amount of moisture released from the food for generating the desired pressure. This study investigated the feasibility of using nitrogen gas as a substitute for steam in the pressure frying system. The effects of various process conditions (source of pressure, frying temperature and pressure) on fried product and frying oil qualities were evaluated. Frying experiments were performed on breaded/battered poultry products including chicken nuggets (homogenous) and chicken fillets (marinated, intact muscle). Efforts were also made to develop rapid methods to determine frying oil quality and discriminate among fresh, marginal and discarded oils using a chemosensory (also known as electronic nose) or Fourier transform infrared spectroscopy (FTIR-ATR). Frying temperature and pressure affected fried food quality. An increase in frying pressure resulted in tender, juicier products with less oil uptake due to high moisture retention. An increase in frying oil temperature resulted in an increased moisture loss, oil uptake resulting in less tender and juicier products. Compared with frying using steam released from food, using nitrogen provided similar or better quality fried products in terms of moisture retention, juiciness and texture. The reused oils from the fryer using nitrogen gas was better in quality than the system using steam as evidenced from the physical, chemical and chemosensory measurements. / Ph. D.

No description available.

Thesis (Msc Food Sc (Food Science))--University of Stellenbosch, 2005. / Near infrared (NIR) spectroscopy prediction models were developed for the rapid determination of the peroxide value, free fatty acid content, specific extinction coefficients at 232 and 270 nm, thiobarbituric acid reactive substances value, pigment, total polyphenol, oleic acid, linoleic acid and saturated fatty acid contents ...

Made available in DSpace on 2014-08-20T13:42:05Z (GMT). No. of bitstreams: 1 Dissertacao_Mauricio_de_Oliveira.pdf: 533629 bytes, checksum: f3d9a8509f749fa69dfcd0cdb1c4f6d3 (MD5) Previous issue date: 2008-02-28 / This experiment were studied the effects of five grains temperatures in the drying, storage environment (controlled and uncontrolled), during 12 months of storage in physical, chemical and physic-chemical characteristics of grains and soybean oil to the production of edible oil and biofuel. The grains were evaluate: moisture degree, volumetric weight, oil content and protein and crude soybean oil were evaluate: acidity index, peroxide index, saponification index, of iodine index and chromatographic profile of fatty acids. The grains were dried in prototype of stationary dryer in the Laboratory of Post-Harvest, Industrialization and Grains Quality, with axial flow air of 7.02 m3.min1.ton-1, in five grains temperatures of: 20, 40, 60, 80 and 100° C, with the total height layer of grains of 60 cm. After the drying, at 4, 8 and 12 months the grains and crude soybean oil were submitted to quality evaluate the grains: moisture degree, volumetric weight, oil content and protein and crude soybean oil were evaluate: acidity index, peroxide index, saponification index, of iodine index and chromatographic profile of fatty acids, the two environmental conditions of storage: controlled (average temperature 17°C and 65% relative humidity) and uncontrolled (average temperature 21°C and 83% relative humidity). With the work was ended that: a) The increase in grains temperature in the drying causes more immediate damage than latent. b) The time storage amending the grain stability with higher intensity in dried in the most drastic conditions and stored without environmental control for a longer time; c) The increase in grains temperature in the drying decrease the hygroscopicity, the hydro-lipid stability, volumetric height, oxidative stability and protein content without change the fatty acids profile; d)The thermal effects typical of the methods drying used on the grain stability are compatible with the soybeans use for feeding and for biofuel; e) For storage time by more than 4 months, mass temperatures above 60⁰C in drying are not indicated. / Neste experimento foram estudados os efeitos de cinco temperaturas da massa dos grãos na secagem, do ambiente de armazenamento, durante 12 meses de armazenamento nas características físicas, químicas e físico-químicas dos grãos de soja na qualidade do óleo para a produção de óleo comestível e biodiesel. Para isso, os grãos foram submetidos à secagem estacionária em protótipos de secador no Laboratório de Pós-Colheita, Industrialização e Qualidade de Grãos. A secagem estacionária foi realizada em secador-piloto, com fluxo de ar axial de 7,02 m3.min1.ton-1, em cinco temperaturas da massa dos grãos: 20, 40, 60, 80 e 100°C, com altura total na camada de grãos de 60 cm. Após a secagem, aos 4, 8 e 12 meses os grãos e o óleo bruto de soja foram submetidos avaliações de qualidade dos grãos: grau de umidade, peso volumétrico, teor de óleo e de proteínas e do óleo bruto de soja: teor de acidez, índice de peróxidos, índice de saponificação, índice de iodo e perfil cromatográfico dos ácidos graxos, nas duas condições ambientais de armazenamento: controlado (temperatura média 17°C e 65% de umidade relativa média) e ambiente não controlado (temperatura média 21°C e 83% de umidade relativa média). Concluiu-se que: a) O aumento da temperatura dos grãos na secagem provoca mais danos latentes do que imediatos; b) O tempo de armazenamento altera a estabilidade dos grãos com maior intensidade nos secados em condições mais drásticas e armazenados sem controle das condições ambientais por tempos mais longos; c) O aumento da temperatura dos grãos na secagem reduz a higroscopicidade, a estabilidade hidro-lipídica, peso volumétrico, a estabilidade oxidativa e o conteúdo protéico sem alterar o perfil de ácidos graxos; d) Os efeitos térmicos típicos dos métodos de secagem utilizados sobre a estabilidade dos grãos são compatíveis com o uso da soja tanto para alimentação quanto para biodiesel; e) Para armazenamento por tempo superior a 4 meses, temperaturas da massa superiores a 60 C na secagem ⁰ não são indicados.

La production de tournesol inclue des interactions complexes entre le génotype et l'environnement tout au long du cycle de la culture. La profondeur de l'enracinement du tournesol est fortement liée au sol, à sa structure et à la disponibilité en eau. La compaction du sol représente un enjeu important dans le contexte actuel de la durabilité des systèmes agricoles, et se caractérise par une diminution de la disponibilité hydrique du sol, une augmentation de la densité apparente et la résistance du sol à la pénétration. L’altération de l'exploration du système racinaire et de ses conséquences sur la croissance du système aérien sous contraintes mécaniques du sol a été explorée pour de nombreuses cultures (maïs Zea mays, Blé Triticum durum, ou de soja Glycine max). Peut d’études ont été réalisée sur le tournesol (Helianthus annuus L.). Parmi ces études seules quelqu’une incluent des cinétiques de croissance, encore moins incluent la qualité de la production. Le but de ce travail est d'étudier i) les modifications du système racinaire causée par la compaction du sol, ii) l'altération du système aérien causé par la modification du système racinaire, et iii) les interactions entre les systèmes. Une synthèse réalisée à partir la littérature et du schéma conceptuel du modèle STICS a permis d’établir un schéma conceptuel théorique retraçant le mécanisme des actions de la compaction du sol sur la plante de tournesol. A partir de ce schéma, deux expérimentations au champ et une expérience en conditions contrôlées ont été construites. En présence de compaction du sol, une diminution de la disponibilité hydrique, une augmentation de la densité apparente et la résistance du sol à la pénétration ont été observées conformément à la littérature. Le stress causé par la contrainte mécanique du sol a induit une réduction de la croissance et de l'exploration du système racinaire. Ceci a engendré une diminution de la surface foliaire, de la biomasse aérienne, et de la hauteur des plantes. Les pertes d'efficacité de l'utilisation des ressources et de rendement ont été observées par des indicateurs indirects. Les analyses de sensibilité de STICS ont été effectuées sur les paramètres d'intérêts, confirmant le seuil à partir duquel la compaction du sol conduit à des effets négatifs sur la plante de tournesol. Des propositions ont été faites pour adapter le modèle à la croissance du système racinaire de tournesol, i) en établissant une liaison directe entre les appareils aérien et souterrain, et ii) en réajustant l'indice de stress provoqué par les variations de densité apparente / The sunflower production takes place throughout complex interactions between the genotype, the crop management and the environment. Sunflower rooting depth is strongly related with soil structural behavior and gravimetric water availability. Soil compaction represents an important issue in the actual context of agricultural system durability, and is characterized by a decrease of soil available water, an increase of bulk density and soil resistance to the penetration. Variation of root system exploration and their consequences on above ground growth and development under soil mechanical constraints have been explored for many crops (Maize Zea mays, Wheat Triticum durum, or Soybean Glycine max), but only few researches have been carried out on sunflower (Helianthus annuus L.). Among them only few includes kinetic aspects and less quality of production. The aim of this work is to study i) the root system modifications caused by soil compaction, ii) the above ground system alteration caused by root system modification, and iii) the interactions between the systems. An analysis carried out from literature and the model STICS conceptual framework lead to the construction of a conceptual framework explaining the mechanism of soil compaction actions on sunflower plant. From this knowledge, two field experiments and a controlled experiment were built. In presence of soil compaction a decrease of soil water availability and an increase of bulk density and soil resistance to penetration were observed as reported in literature. The stress caused by soil mechanical constraint induced a reduction of root system growth and exploration. This induced a decrease of leaf area, shoot biomass, and plant height. The use efficiency of resource and yield lost were observed by indirect indicators. Sensitivity analyses of STICS were done on parameter of interest, confirming the threshold above which soil compaction lead to negative impact on sunflower. Proposition were made to adapt the model to sunflower root system growth, by implementing a direct link between shoot and root growth, and by readjusting the bulk density stress index

Made available in DSpace on 2015-03-26T13:39:59Z (GMT). No. of bitstreams: 1 texto completo.pdf: 3312802 bytes, checksum: ed566888c2b516d81fa9fb871d5632dc (MD5) Previous issue date: 2013-04-10 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The macaw palm [Acrocomia aculeata (Jacq.) Lodd. Martius ex] presents itself as a promising source of vegetable oils, especially as feedstock for biodiesel production. This is due to the high oil content in the mesocarp and almond fruit, the ability to take full utilization of these fruits, besides the great adaptability of this species to climatic conditions. However, missing information for conservation of oil quality after harvesting and storage of fruits, generating the need to develop studies that extend the shelf-life while maintaining the quality of the extracted oil. The objectives of this study were to evaluate the quality and content of mesocarp and almond oil in macaw palm fruits undergoing physical treatments of gamma radiation and drying during storage at room temperature. We carried two experiments: the first one, 120 experimental units were treated with doses of 0, 0.5, 1.0, 3.0 5.0 and 10.0 kGy of gamma radiation and stored for 0, 15, 30 , 45 and 60 days at room temperature. The interaction between dose and storage time was significant. Best visual quality was observed in fruits irradiated with higher doses, in the first days of storage. The free fatty acid from irradiated fruits were lower than the control treatment and doses of 10.0 kGy showed the highest reduction of this index. Gamma radiation reduced the oil accumulation and oxidative stability in the mesocarp. The water content in the mesocarp oil increased with increasing dose and time of storage. The oleic acid and lauric acid are present in higher quantities in the mesocarp and almond oil, respectively. Among the major fatty acids present in the mesocarp and almond oil, oleic acid is the fatty acid that presents major changes during storage. In the second experiment, 100 units experimental of macaw palm fruits were submitted to different combinations of temperature and drying time: 1) without drying the fruits (SS) 2) dried in a oven at 45°C for 4 days (45°C / 4d), 3) drying in an oven at 65°C for 4 days (65°C/4d), 4) drying in an oven at 45°C for 8 days (45°C/8d); 5) dried at 65°C for 8 days (65°C/8d). After this treatment the fruits were conducted to storage at room temperature for 0, 15, 30, 60 and 120 days. There are influence of the drying process and storage time in the evaluated characteristics. Drying at 65°C for 8 days was effective for maintaining stable the free fatty acid index of the mesocarp oil during storage. Drying restricted the accumulation of oil in the mesocarp and almond fruit. The oxidative stability was reduced by drying treatment. Higher concentrations of oleic and lauric fatty acids were found in mesocarp and kernel oils, respectively. The variations observed in the almond oil were with lower intensity than those obtained in the mesocarp oil, and oleic fatty acid is more susceptible to variation during storage. Physical treatments of gamma radiation and drying helped in preserving the fruit. Both had minor progressions in the free fatty index compared to the control treatment during storage, but the drying treatment was more effective in controlling the free fatty acid in the oil of the fruit. The oil accumulation and oxidative stability were reduced in both treatments. The drying treatment provides smaller variations in fatty acid profile for the mesocarp and almond oil. / A macaúba [Acrocomia aculeata (Jacq.) Lodd. ex Martius] apresenta-se como fonte promissora de óleos vegetais, especialmente como matéria-prima para produção de biodiesel. Isso se deve ao elevado teor de óleo no mesocarpo e na amêndoa dos frutos, à possibilidade de completo aproveitamento desses frutos, além da grande adaptabilidade dessa espécie às condições climáticas brasileiras. Entretanto, faltam informações para conservação da qualidade do óleo após a colheita e armazenamento dos frutos, gerando a necessidade de desenvolver estudos que prolonguem a vida pós-colheita, mantendo a qualidade do óleo extraído. Os objetivos desse trabalho foram avaliar a qualidade e teor de óleo do mesocarpo e da amêndoa de frutos de macaúba submetidos a tratamentos físicos de radiação gama e secagem, ao longo do armazenamento, à temperatura ambiente. Realizou-se dois experimentos: no primeiro experimento, 120 unidades experimentais, compostas por 24 frutos de macaúba, foram tratadas com as doses de 0; 0,5; 1,0; 3,0 5,0 e 10,0 kGy de radiação gama e armazenadas por 0, 15, 30, 45 e 60 dias à temperatura ambiente. A interação entre doses e tempo de armazenamento foi significativa. Melhor qualidade visual foi observada em frutos irradiados com as doses mais elevadas, nos primeiros dias de armazenamento. O índice de acidez do óleo de frutos irradiados foram menores que o tratamento controle, sendo a dose de 10,0 kGy a que propiciou maior redução desse índice. A radiação gama reduziu o acúmulo de óleo e a estabilidade oxidativa no mesocarpo. O teor de água no óleo do mesocarpo aumentou com o incremento das doses e do tempo de armazenamento. O ácido oleico e o ácido láurico estão presentes em maiores quantidades nos óleos do mesocarpo e da amêndoa, respectivamente. Dentre os principais ácidos graxos presentes no óleo do mesocarpo e da amêndoa, o ácido oleico é o ácido graxo que apresenta maiores variações no decorrer do armazenamento. No segundo experimento, 100 unidades experimentais, compostas por 24 frutos de macaúba cada, foram submetidas a diferentes combinações de temperatura e tempo de secagem: 1) sem secagem dos frutos (SS); 2) secagem em estufa a 45°C por 4 dias (45°C/4d); 3) secagem em estufa a 65°C por 4 dias (65°C/4d); 4) secagem em estufa a 45°C por 8 dias (45°C/8d); 5) secagem em estufa a 65°C por 8 dias (65°C/8d). Após esse tratamento as amostras foram conduzidas ao armazenamento, à temperatura ambiente, por 0, 15, 30, 60 e 120 dias. Houve influência do processo de secagem e do tempo de armazenamento nas características avaliadas. A secagem a 65°C por 8 dias foi eficiente para manter o índice de acidez do óleo do mesocarpo estável durante o armazenamento. A secagem restringiu o acúmulo de óleo no mesocarpo e na amêndoa dos frutos. A estabilidade oxidativa foi reduzida pelo tratamento de secagem. Maiores concentrações de ácidos graxos oleico e láurico foram encontrados nos óleos do mesocarpo e da amêndoa, respectivamente. As variações observadas no óleo da amêndoa foram de menor intensidade que as obtidas no óleo do mesocarpo, sendo que o ácido oleico é o ácido graxo mais susceptível à variação ao longo do armazenamento. Nos dois experimentos conduzidos, os tratamentos físicos de radiação gama e secagem ajudaram na conservação do fruto em pós-colheita. Ambos apresentaram menores progressões do índice de acidez em relação ao tratamento controle, durante o armazenamento, porém o tratamento com secagem foi mais eficiente no controle da acidez do óleo dos frutos. O acúmulo de óleo e a estabilidade oxidativa foram reduzidos em ambos os tratamentos. O tratamento de secagem proporciona menores variações no perfil de ácidos graxos, tanto para o óleo do mesocarpo, quanto para o óleo da amêndoa.

Thesis (M. Tech. (Agriculture)) -- Central University of Technology, Free state, 2014 / The main objective of the study was to determine the effect of different potassium concentrations and water quality (salt) compared with the current scientifically accepted potassium threshold level and standardised water quality on the yield, oil composition and leaf morphology of rose geranium (Pelargonium graveolens L.) when grown in different potting-bag sizes and root media under temperature controlled condition. To achieve this objective, two trials were conducted. The first experiment evaluated potassium concentrations at 1.3, 3.3, 5.3 and 7.3 mmol L-1 and potting-bag size of 5 and 10 L. Treatments were arranged in a randomised complete block design assigned in a split plot layout. The main plots consisted of potassium concentration and the pottingbag sizes were allocated to sub-plots. Plant height, potassium content, linalool, geraniol, geranyl formate and the citronellol to geraniol ratio (C:G) were affected by potassium. Plant height, number of branches, the branch to height ratio (B:H), foliar fresh mass (FFM) and oil yield were significantly increased when 5 L potting bags were used. Plant foliar mass was significantly increased by the interaction between 5.3 mmol K L-1 and 5 L potting bags. In the second experiment salt levels applied at 1.6, 2.4, 3.2 and 4.0 mS cm-1 and root media (sand and sawdust) were evaluated. A split plot experimental layout was also used in this trial, with the salt levels allocated to the main plots. The sub-plots were allocated to the root medium. High salt level of 4.0 mS cm-1 reduced the number of leaves, plant height, number of branches, B:H ratio, leaf area, chlorophyll content and foliar fresh mass significantly. The number of leaves, leaf area and FFM were significantly increased where sawdust was used. Time of the day significantly affected stomatal conductance, and the opening of most stomata occurred at 10:00. Geranyl formate and the C:G ratio were significantly affected by salt at 4.0 mS cm-1. Salt induced the development of capitates trichomes. The abaxial leaf surface had a higher number of trichomes than the adaxial leaf surface. A strong polynomial (r2=0.97) relationship was found between capitates trichomes and salt levels. High densities of capitates trichomes were found at high salt level of 4.0 mS cm-1. Although the development of asciiform trichomes was induced, it was at an insignificant level. Trichome densities are therefore not affected by salt. It was therefore concluded that the application of 5.3 mmol K L-1 concentration and the use of 5 L potting bags improves the yield and oil quality of rose geranium. It was evident from this study that rose geranium might Salt induced have some degree of tolerance to salt. It was therefore concluded that rose geranium is a moderately salt-sensitive crop.

No description available.