Use of biopolymeric coating hydrophobized with beeswax in post-harvest conservation of guavas.

Biopolymeric coatings are effective in maintaining the chemical and sensory characteristics of fruits and vegetables because they preserve innumerable nutrients effectively for long periods of storage. Coatings based on cornstarch (3%), cassava starch (2%) and gelatin (5%) were synthesized. Beeswax (BW) was added as a hydrophobic agent in the polymeric network at different concentrations relative to the dry base of biopolymer. The biofilm containing 10% BW presented the best results in the water vapor transmission rate (WVTR) and the effect of the BW incorporation was also evaluated from surface roughness and SEM. An 80% increase in elasticity and 15% decrease in solubility indicated resistance against unfavorable environmental conditions. Physical-chemical analysis showed that its use minimized weight loss, guaranteeing adequate ripening of the fruits during 15 days in a regulated environment: 15 °C ± 2 °C, 90% ±2% RH. The sensorial attributes indicated better acceptability of these fruits, demonstrating the potential of this coating.