DOI: 10.36347/sjavs.2016.v03i06.004

Pages: 416-423

This study was designed to determine the effect of processing on the Vitamin C content of five Indian green leafy vegetables namely, Spinach (Spinacia oleracea), Methi (Trigonella foenum-graecum), Lal maath (Amaranthus cruentus), Chauli (Thotakur avepudu) and Bhathua (Chenopodium album). The Vitamin C content of the lemon sample was also estimated using DNPH colorimetric assay, DCPIP, Iodometry and N-Bromosuccinimide titration methods. Among the methods used for Vitamin C estimation of lemon, N-Bromosuccinimide method was found to be most accurate and sensitive. Hence, it was further used to estimate the Vitamin C content in the above mentioned vegetables. Processing methods employed were boiling, blanching and microwave heating the vegetables for particular time interval. The vegetable extracts were subjected to 0.01% N-Bromosuccinimide titration to estimate their Vitamin C content before and after the treatment. Results revealed that maximum reduction in Vitamin C activity of vegetable samples were observed with microwave heating followed by boiling and blanching. Vitamin C content of boiled vegetable samples showed 40-50% reduction in their vitamin C activity, microwave heated samples resulted into 50-75% reduction and blanching lead to minimum reduction i.e. 20-35% as compared to unprocessed vegetable samples. Vitamin C is easily destroyed by excessive heat and water as well as exposure to air. For retention of Vitamin C in cooked foods, it is recommended that foods containing Vitamin C be cooked as fast as possible with less heat and small amount of water.