Control of Browning During the Thawing of Custard Apple Pulp

Abstract

Pulp from custard apple (Annona atemoya Hort.) was treated with 0.1% ascorbic acid and stored in plastic nylon/LDPE bags at -16.3oC. After 2 weeks, 1 month and 3 months, colour and total ascorbic acid were assessed during 6 h thawing at ambient temperature. Comparison of thawing methods; exposing to air, treatment with ascorbic acid solution before exposing to air, and thawing in sealed package showed that the last method is the best to control discoloration and degradation of ascorbic acid for up to 6 h in pulp that had been frozen for up to 3 months. Immersion of pulp in 0.4% ascorbic acid solution before exposure to air at ambient temperature prevents discoloration for up to 4 h of pulp frozen for 1 month, and up to 2 h of pulp frozen for 3 months.