Frozen peas and frozen carrots were obtained from a local supermarket and cooked in a consumer microwave oven (550 watts of cooking power) and in an institutional microwave oven (1150 watts of cooking power). Non-volatile organic acids of each vegetable were identified and quantitated by gas-liquid chromatography. Lactic, succinic, malic and citric acids were identified in peas. Relative concentrations of these acids increased after cooking, particularly in samples cooked without water in a consumer microwave oven. Only malic acid was identified in carrots. Concentration of this acid was not affected by any cooking treatments used in the study. The non-volatile organic acids found in both peas and carrots were not correlated with the sensory scores for flavor of these vegetables. However, total non-volatile organic acids found in peas tended to be negatively correlated with the total chlorophyll retention of all the cooked pea samples.
1Contribution from the Missouri Agricultural Experiment Station Journal Series No. 8093. Approved by the Director.
2Department of Food Science and Nutrition.
3Department of Biochemistry.