This work was carried out with the objective to investigate the behavior of the enzymes pectinmethylesterase (PME) and β-galactosidase (β-Gal) during the ripening of the papaya 'Golden'. The fruits with 15% of yellow peel color were stored in a cold chamber at 20ºC and 85-95 % RH for 11 days. During this stored period it was determined the skin color, pulp firmness and pH. The PME activity observed during the papaya storage showed that this enzyme participated in the hydrolyze process of the cell wall mainly at the beginning of the ripening. The β-Gal activity increased from the 1th day to the end of stored period where reached the maximum activity, although this increase was not gradual. A decrease in the pulp firmness and pH occurred until the 3th day of storage. In this same period, the fruits showed peel color with hue angle values around 80, which corresponds to yellow color. It was verified that the PME acts effectively in the ripening of papaya, however, the decrease in the activity of this enzyme in early periods of storage indicates that the β-Gal has an important role in the firmness loss of papaya cv. Golden.
Carica papaya; pectinmethylesterase; β-Galactosidase; pulp firmness
