Conservação pós-colheita de banana 'Prata Gorutuba' com tratamento hidrotérmico e cloreto de cálcio

Abstract

Refrigerated storage is one of the most commonly used techniques to maintain the postharvest quality of bananas, but depending on the temperature used, it can cause chilling injury. The immersion of the fruits in heated water associated with calcium is an alternative to control this injury. Thus, the objective of the present study was to evaluate the application of calcium chloride after hydrothermia in the maintenance of the post-harvest quality of 'Prata Gorutuba' banana. The experiment was carried out in a Post-Harvest Physiology laboratory, using 'Prata Gorutuba' bananas harvested at maturity stage 2. The experimental design was completely randomized, in a factorial scheme 5 x 7 (concentrations of calcium chloride x periods of evaluations), with four replicates and each repetition composed by a bouquet of four fruits. The fruits were immersed in water at 54° C for five minutes and in a solution of 0, 1, 2, 3 and 4% calcium chloride. Then, packed in low density packages and stored for 30 days in a refrigeration chamber (13.5 ± 1° C and relative humidity of 90 ± 5%), the evaluations were done every five days. They were evaluated for fresh weight loss, peel color, firmness, soluble solids content, pH, titratable acidity, starch and sugars. Starch contents were maintained at the highest concentrations of calcium chloride and chromaticity at concentrations of 2% and 3%. However, the fruits of the control presented lower fresh weight loss, lower soluble solids content and sugars. Firmness, titratable acidity, luminosity and Hue angle were not influenced by calcium chloride concentrations. The treatment with hydrothermia alone shows a better post-harvest quality of the banana 'Prata Gorutuba'. The hydrothermal treatment and immersion in calcium chloride maintained the green coloration of the fruits until fifteen days of storage.