Aplica??o de revestimentos comest?vel em caqui "Mikado" (Diospyros kaki) minimamente processado

• Autor(a) principal: Neves Junior, Augusto C?sar Vieira
• Data de Publicação: 2009
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFRRJ
• Texto Completo: https://tede.ufrrj.br/jspui/handle/tede/536
• topic: processamento m?nimo; destaniza??o; filme comest?vel; minimal processing; astringency reduction; edible coating; Agronomia

Minimally processed products are safe and ready to eat, in spite of adding value, has a short life. Edible coatings can be an important tool to ensure the quality and increase the shelf life of minimally processed products, including persimmon. The 'Mikado' variety Persimmon has astringency and need a specific astringency process to get a minimally processed product with quality. Therefore, the objective of this work was to develop and characterize the edible coatings for use in 'Mikado' minimally processed persimmon. It was necessary to determine the exposure time of the fruit to alcohol vapor until the decrease of astringency. It was performed the flowchart for the fresh-cut of persimmon evaluating the quality of the final product. Evaluations of thickness, gas permeability, mechanical properties of coatings applied were also performed. It was also verified the efficiency of use 70% alcohol (7.00 mL ?lcool.Kg-1 fruit) to reduce astringency. There were performed the following analysis: firmness, pH, total soluble solids (? Brix), total titratable acidity, total tannins and weight loss and sensory analysis during the process. These analyses were necessary to determine the time of exposure to the alcohol vapor to decrease the concentration of soluble tannic acids in fruit that it was not tasted by panelists and determine that concentration. It was evaluated persimmon storage with and without coatings. Three experiments were conducted during this work. In the first experiment, it was set up two coatings which were used in the second trial of minimally processed. It was evaluated four different types of coatings: cassava starch, sodium alginate, carboxymethyl cellulose (CMC) and bovine gelatin. In the first experiment (edible coating), it was set up two coatings which were used in the experiment of minimally processed. Four different types of coatings were evaluated: cassava starch, sodium alginate, carboxymethyl cellulose (CMC) and bovine gelatin. In the second experiment (astringency reduction) it was defined the time required to keep the fruits in alcohol atmosphere to reduce total soluble tannins tasted by panelists. The times tested were: 10 hours, 36 hours, 55 hours, 83 hours, 107 hours, 130 hours and 155 hours. It was defined a flowchart for persimmon minimally processed. The best coatings applied in minimally processed persimmon were the cassava starch and CMC. The firmness of the fruit remained until to 55 hours of exposure to alcohol vapor. Fruits were exposure to 83 hours or up caused loss firmness below that it is commercially tolerated. The astringency was not tasted by panelists from 55 hours exposure of alcohol vapor. The threshold detection of total soluble tannin in the pulp of fruit was 0.8161 ?g.100g-1. The tannins content decrease with the increasing exposure of fruit to alcohol vapor. The reduction of astringency with 70% alcohol vapor may not be the most indicated method due to high losses in this step (21.76%). The minimally processed fruits treated with CMC coating showed less dark spots in the pulp than the other treatments and all treatments were microbiological adequates.