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The nutritional quality and antioxidant activity of organic and conventional green beans were compared in a series of experiments. Firmness, percent dry matter, carotenoids and chlorophyll contents, respiration rate, vitamin C and proteins were evaluated. Hydroxyl radical scavenging activity, SOD, APX and POX were also analysed. In a second experiment, organic green beans treated with hexanal formulations were stored with untreated at 12⁰C in the refrigerator for a period of three weeks during two seasons. The results of the experiment showed higher levels of most of the parameters measured in organic green beans (with significant differences in firmness, carotenoids and chlorophyll b), except for respiration, vitamin C, antioxidant activity(hydroxyl radical scavenging) and APX where conventional green beans were higher and showed significant differences in respiration and vitamin C. The storage experiment showed a decrease in firmness and fresh weight and increase in respiration during storage for both seasons. Carotenoids and chlorophyll contents showed decrease in concentrations during the first week and increased during the second week of storage.

Made available in DSpace on 2014-12-17T15:01:37Z (GMT). No. of bitstreams: 1 UlianaKLM.pdf: 961096 bytes, checksum: ea96b714e4b16cdf30f7ab8d544fc05c (MD5) Previous issue date: 2004-05-28 / 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

Thesis ( M.Sc.(Horticulture)) -- University of Limpopo, 2017. / Refer to document / National Research Foundation of South Africa, and the Agricultural Research Council-Universities Collaboration Centre

Les folates sont des vitamines hydrosolubles, impliqués dans la limitation d’apparition de pathologiestelles que les anomalies de fermeture du tube neural. L’homme est dépendant de son alimentation pourcouvrir ses besoins en folates. Les légumes sont une des sources importantes de folates. Dans un mêmetemps, les légumes verts sont principalement consommés à partir de produits transformés, cuits,surgelés ou appertisés. Il est donc important de maitriser les paramètres de la transformation afin depréserver au mieux les teneurs finales en folates. L’objectif de ce travail a donc été d’identifier l’impactdu procédé de transformation (industriel et domestique) sur la perte en folates. Deux procédésindustriels ont été étudiés : la surgélation des épinards et l’appertisation des haricots verts, lestraitements domestiques ont consisté en la cuisson de légume dans de l’eau à ébullition ou à la vapeur.Les traitements thermiques (blanchiment et cuisson vapeur) n’induisent pas de diminutionssignificatives de la concentration en folates. En revanche, des pertes sont observées lorsque les légumessont en contact étroit avec l’eau. Cette étude a permis de mettre à jour deux mécanismes de perte, ladiffusion et la dégradation thermique. La diffusion des folates a été étudiée à l’échelle du laboratoire, lesconstantes de diffusion des folates ont été déterminées. La diffusion est largement influencée par lamatrice elle-même, plus que par la température ou le pH. La part de la dégradation thermique, etnotamment l’oxydation, ne peut être exclue au cours de la diffusion. C’est pourquoi des cinétiques dedégradation ont été réalisées à différentes température et différentes teneurs en oxygène, à partir depurées d’épinards et de haricots verts ainsi que sur des solutions modèles. L’oxygène joue un rôleimportant dans la dégradation chimique, notamment dans les solutions modèle. Les matrices végétalesconstituraient donc une barrière à l’oxydation des folates. Les folates sont globalement assez bienconservés au cours du procédé de transformation. Une des pistes de recherche qui prendrait un sens dansla continuité de ce travail serait l’étude de l’impact des procédés de transformation sur labioaccessibilité des folates / Folates are water-soluble vitamins, involved in the limitation of diseases such as neural tube defects.Man is dependent on his food to cover its folates’ needs. Fruits and vegetables, particularly greenvegetables are one of the major dietary sources of folates. In the same time, green vegetables are mainlyconsumed as processed products, cooked frozen or canned. It is therefore important to controlprocessing parameters in order to preserve folates content in final products. The aim of this study was toidentify the impact of processing (industrial and domestic) on folates loss. Two industrial processingchains were studied: spinach freezing chain and green beans canning chain, home treatments consistedin vegetables boiling or steaming. Thermal treatments (blanching and steaming) did not induce asignificant decrease in folates concentrations. In contrast, losses were observed when vegetables were inclose contact with the water. This study identifies two mechanisms of losses, leaching and thermaldegradation. Folates diffusion was studied on a laboratory scale, the diffusion constants for folates weredetermined. Diffusion was more influenced by the matrix, than by temperature or pH. Some of thermaldegradation, including oxidation, can not be excluded during leaching experiments. Degradationkinetics were performed at different temperature, with different oxygen contents, from spinach andgreen beans puree as well as model solutions. Oxygen plays an important role in chemical degradation,especially in model solutions. Plant matrix seemed to have protective effect, maybe as a barrier tooxygen. Folates are generally fairly well preserved during processing. One of the perspectives would bethe study of the impact of processing on folates bioaccessibility

Thesis (M.Sc. (Agricultural economics)) --University of Limpopo, 2012 / Refer to document / Water Research Commission (CSIR)

Transverse cotyledonal cracking (TVC) was characterised at physiological, biochemical and molecular levels in three common bean (Phaseolus vulgaris L.) cultivars: Imbali, Tongaat and Tokai. The incidence of TVC was determined visually on ten-day old seedlings and was expressed as the number of cracks per plant. The effect of Ca++ on TVC incidence was examined by enhancing the calcium content of seed cotyledons using calcium salts in seed priming and coating. EDAX was used to quantify the cotyledonal calcium content. Activities of the pectinolytic enzymes polygalacturonase (PG) and pectin methylesterase (PME) were assayed at dry seed, VC, R4 and R6 phenophases of the bean plant, and zymogram electrophoresis was used to identify the two enzymes. The results showed that cultivars Imbali, Tongaat, and Tokai were susceptible resistant and intermediate, respectively, with respect to TVC incidence. Calcium uptake was higher in Tongaat cultivar (P= 0.05) compared with Imbali and Tokai, irrespective of calcium salt enhancement. Vigour was significantly reduced (P< 0.01) by both coating and priming. TVC significantly lowered yield (P= 0.05) in the susceptible Imbali cultivar. Zymogram analysis identified lytic bands at ~45kDa (PG gel) and ~30kDa (PME gel). The activity profile of PME was similar for all cultivars. However, PG activity of susceptible Imbali was high in dry seeds and at the R4 and R6 stages of plant development, whereas the more resistant cultivars displayed high activity at the VC stage only. It is concluded that high PG activity at R4 stage is a more reliable determinant of green bean propensity to cotyledonal cracking. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.

Los objetivos de la presente tesis fueron comparar el efecto de tres técnicas de cocción en varios vegetales y su selección para cada producto estudiado. Para ello, los trabajos realizados han considerado los cambios en las propiedades físico-químicas, nutricionales, sensoriales y la microestructura. Asimismo, como respuesta al reto de aplicar tratamientos equivalentes en firmeza con diferentes técnicas de cocción se ha propuesto una metodología que combina los diseños experimentales de superficie respuesta (RSM) con análisis instrumentales y sensoriales. Los tratamientos térmicos estudiados fueron la cocción tradicional (TC¿ agua hirviendo a 100 °C) junto con dos tratamientos que utilizan el vacío en el procesado: el cook-vide (CV¿ cocción a vacío continuo donde los alimentos están en contacto con agua hirviendo a baja presión) y el sous-vide (SV¿ cocción de alimentos previamente embolsados a vacío donde el alimento está separado del agua de cocción). Los vegetales objeto de estudio fueron la patata morada (Solanum tuberosum L. var. Vitelotte), la judía verde (Phaseolus vulgaris L. cv. Estefania), la zanahoria (Daucus carota L. cv. Nantesa) y la col lombarda (o repollo colorado) (Brassica oleracea convar. capitata var. capitata f. rubra). Considerando muestras con firmeza instrumental similar y las propiedades nutricionales y sensoriales (especialmente aroma y sabor), incluyendo la aceptación del consumidor, se recomienda la cocción SV para los vegetales estudiados, excepto para la zanahoria. En el caso de este vegetal el cocinado tradicional (100 °C) mantiene la aceptabilidad del consumidor y aumenta la extracción de los ß-carotenos por lo que se considera más recomendable que el SV. / Iborra Bernad, MDC. (2013). Comparison of vacuum treatments and traditional cooking in vegetables using instrumental and sensory analysis [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/32953