The effect of antifungal hot-water treatments on papaya postharvest quality and activity of pectinmethylesterase and polygalacturonase.

The effect of antifungal hot-water treatments (AHWT) at 55 °C for 0, 3, 6 and 9 min on quality attributes and cell-wall enzymatic activity during storage at 25 °C was investigated in papaya fruit. The total soluble solids (TSS), pH, titratable acidity (TA), firmness and fresh weight loss were not affected, whereas color on skin was negatively affected by the treatments of 6- and 9-min. However, the skin color was not different between the 3-min treated fruit and the untreated fruit during the storage. Decay was delayed and reduced by AHWT. We observed that the 3-min treatment of 55 °C did not affect softening and quality of papaya cv Maradol when applied as a pesticide-free treatment at color-break stage of papaya. PME (Pectinmethylesterase) and PG (Polygalacturonase) activities were not significantly affected by AHWT. We concluded that the AHWT did not affect the softening process from papaya pulp since the cell-wall enzyme activity (PME and PG) was not altered by treatments.