EDIBLE COATING, BASED ON CASSAVA STARCH, INCORPORATED WITH POTASSIUM SORBATE IN THE POSTHARVEST PRESERVATION OF PAPAYA

Papaya has intense metabolic activity, resulting in a short shelf life after harvest. Studies have shown that the use of edible coating (EC) extend the postharvest shelf life of climacteric fruits. This study evaluated the effect of EC based on starch (S) with and without incorporation of potassium sorbate (PS) at 0.1%, in papaya fruits. The treatments were A2%, A2%PS, A4% and A4%PS, in addition to a control (uncoated fruit), being later stored at room temperature (25°C) and relative humidity of 85% for 12 days. During the experiment, every 2 days the physicochemical parameters of weight loss (WL), total soluble solids (TSS), skin color (L*y ΔE), pulp firmness (PF), pH and titratable acidity (TA) (% citric acid) were measured. The results showed that, the EC had a significant effect (p≤0.05) on the parameters evaluated, in comparison with the control treatment. Being A4%PS, which reduced WL (7.6%), and maintained PF (2.33 N) to a larger extent, compared to the control (18.7% and 0.31 N) and the other treatments, because the EC exerts a barrier to water vapor and gases (O2, CO2, among others), improving this property with the incorporation of low levels of PS in the matrix. On the other hand, it also maintained the quality parameters of the fruit such as color (L*= 32.12 and ΔE= 12.07), TSS (8°Brix), pH (4.97) and TA (1.32%), while the control (color: L*= 50.20 and ΔE= 52.04; TSS= 10.50°Brix; pH= 5.13 and TA= 1.80%). The results suggest that the use of EC, specifically A4%PS, prolonged the shelf life of the fruit, improving its postharvest storage capacity for 12 days compared to the control, which matured in 8 days, after which it lost its marketability.