The effect of cooking with kanwa alkaline salt on the chemical composition of black beans (Phaseolus vulgaris)

The effect of cooking with kanwa alkaline solution on the chemical composition of black beans (Phaseolus vulgaris) was analyzed. Crude lipids and water-soluble fractions were extracted from three flour samples obtained from raw black beans and black beans cooked in kanwa solution or distilled water. Heat processing resulted in significant reduction in crude lipids, proteins and neutral sugars. Neither heat treatment induced changes in the levels of palmitic, stearic, oleic or linoleic acids, present in the crude lipid fraction. There was a significant change in both the total amino acids and the total essential amino acids. Heat treatment in alkaline solution decreased the levels of isoleucine, lysine, tyrosine, phenylalanine, threonine and valine. There was also a decrease in the galactose content after this heat processing.