EFFECT OF TRADITIONAL COOKING METHODS ON THE ASCORBIC-ACID CONTENT OF SOME NIGERIAN LEAFY AND FRUIT VEGETABLES

Representative samples of vegetables purchased from a local market, without the age and time of harvest being known, were analysed for ascorbic acid content. The ascorbic acid content in fresh samples was highest in Hibiscus esculentus L. with 203 mg 100 g ± 51·38 and lowest in Vernonia amygdalina with 30·95 mg 100 g ± 4·85. After laboratory preparation and cooking of the vegetables, the loss of this vitamin was significant in all the samples. The use of firewood as the source of heat and of mudpot utensils caused a higher loss of ascorbic acid in all the vegetables than cooking with gas using aluminium pots. © 1979.