Influenţa procesării culinare asupra conţinutului în acid ascorbic al unor produse vegetale

Abstract

This work analyses the modification of the ascorbic acid (vit. C) content within some vegetable species (potato, tomato, cabbage and parsley) during culinary processing. The vegetable products have been subjected to some operations, such as: wetting, cutting (finely chopping), boiling, frying, sterilizing, pickling, determining the values of vit. C, before and after processing. It also has analysed the water where culinary processing was accomplished, that is the water in which the legumes were introduced and maintained, for a period of time (before thermic processing), as well as the water where all studied vegetable products have been boiled. The evaluation of the tests effected during experiments has shown, in all cases, greater or smaller modifications of this bioactive component. Thus, the thermic processsing, depending on its type and on analysed vegetable products, has determined modifications of the acid ascorbic content, in the sense of reducing of this one. Also, within the water where the vegetables were boiled, the biochemical tests have pointed out a variable content of ascorbic acid. Subjected to the thermic processing, potato tubers have lost some 25% ascorbic acid through boiling and 17% through frying process. Analysing the potatoes boiling water, it has find ascorbic acid representing over 20 % of the initial content of the potato tubers. In tomatoes, the thermic process has reduced the vit. C up to about 73% of the initial content, the boiling water having some 17% of the same vitamine. The tomatoes boiling water is usually valued, so that the vitamine loss is only 10%. The thermic processing of cabbage has modifyed the ascorbic acid content, reducing it with some 35%. Because some 27% of the ascorbic acid was found within boiling water, the total loss of this vitamine was around 7%. As to the parsley, the boiling process has decreased the ascorbic acid content more (with 10%) in root tissues then leaves