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Previous issue date: 2016-06-02 / CAPES / Banana is a perishable fruit, as it ripens fast and cannot be adequately preserved by the cold, resulting in large post-harvest losses. The application of preservation techniques, such as osmotic dehydration, reduces losses of the commodity in post-harvest stage, extend its shelf-life, while not severely affecting its nutritional values, and functional and sensorial properties, which makes it at processing alternative for the fruit. The aim of this study is to evaluate the kinetics of osmotic dehydration, as well as the quality of the osmotically dehydrated samples in terms of color, texture, and antioxidant capacity, using fructo-oligosaccharide, corn syrup and the mixture of both, under different temperatures. To determine the kinetics, the fruit, cut in cubes, was dehydrated in different solutions, under temperatures of 40, 50 and 60 ? C. The kinetics of water loss (WL) and solid gain (SG) were evalueted at 30, 60, 90, 120, 180, 240, 360, 720 to 1440 minutes. The analysis of variance was used to verify the effect of each solution and temperature on kinetics. The kinetic parameters were modeled based on the equations of Peleg, Page modified and Barbosa Junior et al. using non-linear regression. The time to reduce the dehydration rate or penetration to one third of its initial values (t(1/3)) and the process average time (t(average)) were obtained on the Barbosa Junior et al. model The quality of the samples was accessed at these two times, in different solutions under different temperatures. For such, the variation of the instrumental parameters of color, antioxidant capacity (FRAP, DPPH and total phenolic content), and texture (axial compression tests) of samples, in nature as well as processed, were verified. The WL was not affected significantly by the type of solute used, however, the temperature presented significant influence over these parameters (p < 0.05). The experimental data for the WL was adequately adjusted to the Peleg and Page modified models with coefficients of determination (R?) superior than 0.98, mean relative error (E) inferior than 6.5% in all treatments. The water loss content values varied from 15.75 to 28.79% at time t(1/3), while for the time t(averege) 15.75 to 30.27% between treatments. The process of osmotic dehydration had affect on the quality of the final product, showing significant differences between the fruits in natura and processed state, in terms of color, antioxidant capacity and texture of the samples. / A banana ? um fruto perec?vel, pois sofre r?pido amadurecimento, n?o pode ser devidamente conservado pelo frio, sendo acometido por grandes perdas p?s-colheita. A utiliza??o de t?cnicas de conserva??o, como a desidrata??o osm?tica, reduz as perdas p?s-colheita, estende a validade comercial, n?o acarreta em severas altera??es nas caracter?sticas nutricionais, funcionais e sensoriais e mostra-se como uma alternativa de processamento para este fruto. O objetivo desde trabalho foi avaliar a cin?tica da desidrata??o osm?tica, bem como, a qualidade das amostras desidratadas osmoticamente em termos de cor, textura e capacidade antioxidante, utilizando fruto-oligossacar?deo, xarope de milho e a mistura de ambos, em diferentes temperaturas. Para determina??o da cin?tica, a banana, cortada em cubos foi desidratada nas diferentes solu??es, sob as temperaturas de 40, 50 e 60 ?C. As Cin?ticas de Perda de ?gua (PA) e ganho de s?lidos (GS) foram avaliadas nos tempos 30, 60, 90, 120, 180, 240, 360, 720 e 1440 minutos. A an?lise de vari?ncia foi usada, a fim de verificar o efeito do tipo de soluto e da temperatura na cin?tica. Os par?metros cin?ticos foram modelados de acordo com a equa??o Peleg, Page modificado e Barbosa J?nior et al. utilizando regress?o n?o-linear. A partir do modelo de Barbosa J?nior et al., obteve-se o tempo para reduzir a taxa de desidrata??o ou impregan??o a um ter?o de seus valores iniciais (t(1/3)) e o tempo m?dio de processo (t(m?dio)). A qualidade das amostras foi avaliada nestes dois tempos, nos diferentes solutos e temperaturas. Para tal, foram verificadas a varia??o dos par?metros instrumentais de cor, a capacidade antioxidante (FRAP, DPPH e teor de fen?licos totais) e a textura (ensaios de compress?o axial) das amostras in natura e processadas. A PA n?o foi afetada significamente pelo tipo de soluto empregado, no entanto, a temperatura apresentou influ?ncia significativa neste par?metro (p < 0,05). Os dados experimentais para a PA se ajustaram adequadamente ao modelo de Peleg e Page modificado e obtiveram-se coeficientes de determina??o (R?) maiores do que 0,98, desvio relativos m?dios (E) inferiores a 6,5% em todos os tratamentos. O modelo do tempo de n-redu??o da taxa de desidrata??o se mostrou uma boa alternativa na defini??o do tempo de processamento das amostras submetidas ? desidrata??o osm?tica. Os valores de perda de ?gua variaram de 15,70 a 28,79% no tempo t(1/3), enquanto que para o tempo de t(m?dio) de 15,75 a 30,27% entre os tratamentos. O processo de desidrata??o osm?tica influenciou na qualidade final dos produtos, apresentando diferen?as significativas entre a fruta in natura e a processada para varia??o dos par?metros de cor, a capacidade antioxidante e a textura das amostras in natura e processadas.
| Identifer | oai:union.ndltd.org:IBICT/oai:localhost:jspui/1609 |
| Date | 02 June 2016 |
| Creators | LANDIM, Ana Paula Miguel |
| Contributors | Barbosa, Maria Ivone Martins Jacintho, Barbosa, Maria Ivone Martins Jacintho, Manh?es, Luciana Ribeiro Trajano, Mancini, Maur?cio Cordeiro |
| Publisher | Universidade Federal Rural do Rio de Janeiro, Programa de P?s-Gradua??o em Ci?ncia e Tecnologia de Alimentos, UFRRJ, Brasil, Instituto de Tecnologia |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | Portuguese |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/doctoralThesis |
| Format | application/pdf |
| Source | reponame:Biblioteca Digital de Teses e Dissertações da UFRRJ, instname:Universidade Federal Rural do Rio de Janeiro, instacron:UFRRJ |
| Rights | info:eu-repo/semantics/openAccess |
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