Effect of Packaging Material on the Non-enzymatic Browning of Litchi Juice

摘要

A storage study of litchi juice packed in glass bottles and plastic pouches at 40°C to analyze effects of packaging material on ascorbic acid, browning and total phenol in litchi juice. The initial concentration of ascorbic acid in litchi juice was 150.74 mg/L and this was found to decrease by 30.56 and 26.12 mg/L after six weeks in glass bottles and plastic pouches. Dissolved oxygen concentration of litchi juice was decreased continuously in glass bottles and decreased fast first, then increased slowly in plastic pouches. Total phenol of litchi juice packed in glass bottles and plastic pouches decreased continuously. Litchi juice non-enzymatic browning attributed to ascorbic acid degradation, mail lard reactions and polyphenol oxidation polymerization. The oxygen which permeated through plastic packaging material and dissolved in litchi juice promoted ascorbic acid degradation.