Assessment of the Extent of Losses in Ascorbic Acid Content of selected Vegetables subjected to Common Cooking Methods

The effect of different cooking methods, that is, covered lid cooking (CLC), microwave cooking (MW) and stir frying (SF) on the ascorbic acid (AA) content of selected vegetables was studied. The optimum cooking time was adjudged by the sensory evaluation of the vegetables. The maximum overall acceptability of vegetables, that is, spinach, fenugreek, broccoli, cabbage and capsicum was at 15, 10, 5, 10 and 10 min during CLC and MW, while it was at 10, 15, 5, 10 and 10 min during SF, respectively. The ascorbic acid content of vegetables ranged between 28.0–109.9 mg/100g, the maximum and minimum values being for capsicum and spinach, respectively. Ascorbic acid content in cabbage was 105.3mg, which was comparable to capsicum while intermediate values were found for broccoli (45.7mg) and fenugreek leaves (42.0mg). The maximum loss of AA in spinach and fenugreek leaves was during SF, that is, 35.7% and 43.8%, respectively. MW resulted in 29.7% and 34.7% losses in two vegetables while CLC caused 30.9% and 31.4% loss respectively. In comparison to other analysed vegetables, broccoli showed the least loss of AA when subjected to different cooking methods. The losses were 19.0% and 18.4% for CLC and SF, respectively. The minimum loss was during MW (14.8%). Cabbage and capsicum showed maximum losses of AA, that is, 39.1% and 36.9% during SF, while least losses were during MW, that is, 27.2% and 26.6% respectively. The results revealed that SF caused maximum loss in all the vegetables except broccoli, where it was comparable to CLC. MW resulted in minimum loss of AA in the case of spinach, broccoli, cabbage and capsicum. The present study concluded that MW is a better method as it resulted in the least loss of ascorbic acid as compared to CLC and SF.