Study on L-ascorbic acid contents from exotic fruits

Abstract

Four commonly consumed exotic fruits from market were analysed for their Vitamin C content. Extracts of fruits were investigated at different temperatures. In order to evaluate the Vitamin C from fruit extracts, the redox iodometric titration with iodine/iodide method was used. The redox titration was preferable to acid-base titration, because of the number of other species present into citrus extract, which could act as acids, but relatively few interfered with the oxidation of ascorbic acid by iodine. The content of Vitamin C depended on the variety, location of cultivation and growing season. The effects of cooking were also noticed in this experimental work. Cooking processes have commonly destroyed the large quantities of ascorbic acid. Frozen fruits presented low differences as concerns the Vitamin C content. The fruits stored at 10° C have shown stability for Vitamin C.