Estudo da atividade de água em co-produtos da indústria de sucos: sementes de maracujá, casca de laranja e cascas de manga

• Autor(a) principal: Souza, Silvio José Ferreira de [UNESP]
• Data de Publicação: 2015
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/127879; http://www.athena.biblioteca.unesp.br/exlibris/bd/cathedra/01-09-2015/000844423.pdf
• topic: Tecnologia de alimentos; Suco de frutas; Resíduos industriais; Histerese; Alimentos; Modelos matematicos

Sorption isotherms are important for predicting the drying kinetics behavior and storage conditions of agroindustrial wastes such as passion fruit seeds, orange skin and mango skin, which are studied as raw material for industrial applications. The knowledge of such properties is useful to design equipment or operations for storage or processing purposes. Thus, the present research aims to determine the water activity content in juice industry waste. For this, the equilibrium moisture content for sorption isotherms of passion fruit seeds, orange skin and mango skin were determined using the static gravimetric method at temperatures between 20 - 70 oC and water activity range of 0.056 - 0.873. All experimental sorption curves show a decrease in equilibrium moisture content as the temperature increasing. Also, curves type III were observed, showing a behavior of materials with high carbohydrate content and, high water content at low water activity. Theoretical and empirical models were used to represent the experimental values of the sorption isotherms. For passion fruit seeds, the empirical Henderson model shows the best fitting accuracy to describe the adsorption isotherms curves. Moreover, the Guggenheim, Anderson, and de Boer (GAB) model presented the best fitting accuracy to modeling the experimental adsorption isotherms of orange skin and the desorption and adsorption isotherms of mango skin. Finally, with the GAB parameters was possible confirm, in energetic terms, the difference between adsorption and desorption isotherms observed in the hysteresis phenomenon in mango skin