Quality of 'Nam dorkmai', 'Rad' and 'Pimsen Daeng's Mangoes subjected to Vapor Heat Treatment

Abstract

Nam Dorkmai', 'Rad' and 'Pimsen Daeng' mango fruits of two sizes from central and northern porduction areas were subjected to vapor heat treatment (VHT) under saturated condition until fruit centertemperatures were raised to 47.0 C and 48.5 C and maintained for 0, 60 and 120 min. Immediately after treatment, treated fruits were forced-air cooled for 1 hr and then kept ripen in temperature/humidity controlled chamber of 25 C, 70-80% RH. Weight loss was consistently lower in treated fruits. No adverse effect on total soluble soilid (TSS) and acidity was observed on the treated fruits. The incidence of anthracnose and stem end rot was also reducted by the treatment. It was observed that 'Nam dorkmai', 'Rad', and 'Pimsen Daeng' mangoes were all damaged by the VHT. The main injuries to the fruits were due to the presence of white sopt and spongy tissue in the inner portion of the mesocarp. The symptoms were not apparent until the ripe stage and the injured fruits showed no visible external lesions.