Abstract

                                Mango pulp (Totapuri variety) was foamed by adding egg albumen (5, 10 and 15%) and stabilized with methyl cellulose (0.5%). The foamed pulp was dried at four drying temperatures viz. 60, 65, 70 and 75°C in a batch type cabinet dryer by maintaining three foam thicknesses viz. 1, 2 and 3 mm. From the drying study, it was observed that, the drying time required for foamed mango pulp was lower than non-foamed pulp at all selected temperatures. The drying rate constant ‘k’ value decreased with increase in pulp thickness during drying. The results of the biochemical analysis showed a significant reduction in ascorbic acid, total soluble solids and (b-carotene in the mango flakes dried at higher temperatures when compared to the pulp dried at lower temperature of 60°C. Also, these biochemical changes were significantly higher in 2 and 3 mm than in 1 mm thick foam dried samples. The study also revealed that there was no significant change in other biochemical constituents such as pH, acidity and total sugar due to the increase in drying temperature and foam thicknesses. From the foam mat drying study, it was concluded that the mango pulp treated with egg albumen (10%) with methyl cellulose (0.5%) and dried at 60°C with one mm foam thickness retained significantly higher quality traits (P < 0.05) than that of other foaming and drying treatments.

Key words : Totapuri mango, egg albumen, methyl cellulose, foam mat drying, foam thickness, drying rate constant, mango pulps, mango flakes and powder