The preservative effect of bee wax and calcium chloride coating on the quality and firmness of graviolas (Annonamuricata L.)

The ripening of soursop is marked by significant changes in the firmness of the fruit, with pulp softening being the main cause of quantitative and qualitative losses during commercialization. To minimize this problem, fruits of the 'Morada' soursop were immersed in solutions of distilled water (control), beeswax (3%), CaCl2 (3%) and the combination of beeswax + 3% CaCl2 for a period minutes and then stored at 15ºC for 16 days. Analyzes of physical-chemical and biochemical quality were investigated at four-day intervals. Considering the immersion solutions using isolated beeswax (3%) and CaCl2 (3%) resulted in satisfactory quality aspects in relation to the control, but it is in the combined use (beeswax + 3% CaCl2) that results were observed significant (p<0.05) such as less loss of fresh weight (6.93%), greater firmness (32.18 N), better balance of soluble solids (11.98ºBrix), titratable acidity (0.82 g. 100 g-1 citric acid), SS / AT (14.60), pH(5.58) and less degradation of starch (8.98 g.100g-1) and total pectin (0.25 g.100g-1), in addition to less activity of the enzymes amylase, pectinamethylesterase and polygalacturonase in relation to the other treatments, especially the control. These results indicate that the combined use of 3% beeswax + 3% CaCl2 preserves the physical-chemical quality and firmness of the pulp by reducing the activity of enzymes associated with the cell wall, thus suggesting a delay in fruit ripening.