Caracterização de filmes comestíveis do amido fosfatado da Swartzia burchelli para aplicação pós-colheita em tomate cereja

Abstract

Conventional corn and cassava starches are being increasingly demanded in the market due to its high demand for edible purposes, the production of biofuels, biodegradable plastics in soil covers cultivation, films and edible coatings for fruits and seeds. Therefore, it is necessary to search for unconventional starches, such as the S. burchelli , to meet part of the demand in the market. The present study aimed to modify the starch phosphate by S. burchellli in order to prepare and characterize edible films for their application in post-harvest technology in cherry tomato. Starch was extracted from seeds of the fruits of S. burchelli and phosphatic acid with different concentrations of sodium tripolyphosphate (ATPS) at different reaction times (t), conducted randomized in double factorial design 22 with additional treatment with four repetitions. Of treated starches were determined phosphorus content. Edible films were made based on native starch and phosphate using the scattering technique, a double factorial: type starch [TA: native starch (ANSB) and phosphate starches (AF1, AF2 and AF3), previously selected] and plasticizer (GLI: 5, 10, 15, and 20% glycerol). The prepared films were characterized for their thickness, permeability to water vapor (Pva), water solubility, and mechanical testing (strength and deformation). Selected as Pva, movies edible coatings were applied to cherry tomato. Completely randomized factorial design was applied 4x8, being three treatments with different Pva of edible coatings and other uncoated (control), and eight times of assessment. The edible coatings were prepared using the same spreading technique with modifications. After the fixed and dried toppings, fruits were stored for 21 days at 10±2°C and 80±5% relative humidity. The mass loss, soluble solids, titratable acidity, maturation index and firmness were measured every three days in storage. The results of phosphate were subjected to analysis of variance at the level of 6% probability. Phosphate starches showed phosphorus content within the set by law and may be used in foods. Edible films showed good appearance without fixuras or brittle. The glycerol concentration and type of starch influence the characteristics of the Pva films and increasing deformation and reduced water solubility and strength at break of the processed edible films. The application of the edible tomatoes coverage provided the stability of the maturation index and delayed loss of the firmness of the fruit during storage. Therefore, it was noted that with higher concentrations of glycerol (20%) films were more permeable to water vapor and less soluble in water. The edible coatings S. burchelli left most brilliant and attractive fruits of cherry tomato. And for the maintenance of these postharvest fruit toppings with higher Pva were more effective in providing better storage conditions.