Influence of antioxidant spices on the retention of beta-carotene in vegetables during domestic cooking processes

Considerable amounts of beta-carotene were lost during the two domestic methods of cooking commonly used, namely, pressure cooking and open pan boiling, the loss ranging from 27 to 71% during pressure cooking and 16-67% during boiling for the four vegetables examined in this study. Pressure cooking of green leafy vegetables resulted in a greater retention of this provitamin. In the presence of red gram dhal, which is a common ingredient in the diet, there was an underestimation of beta-carotene due to poor extractability. Inclusion of acidulants-tamarind and citric acid-along with these vegetables brought about some changes in the level of retention of beta-carotene. The antioxidant spice turmeric generally improved the retention of beta-carotene in all four vegetables studied. Onion also had a similar effect. The combinations of acidulants and antioxidant spices also improved the retention of beta-carotene during cooking. This effect seemed to be additive in the case of processing of amaranth by boiling.