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The triglyceride and phosphatide contents of seven varieties or types of dry beans and the Alaska pea were determined. The triglyceride content ranged from 0.89% for Alaska peas to 1.54% for Michelite beans. The phosphatide content averaged near 1 %, except for lima beans which averaged 0.88%. Gas-liquid chromatography was used to study the component fatty acids of the triglycerides and phosphatides. The main fatty acids of the triglycerides were palmitic, oleic, linoleic, and linolenic. Small amounts of myristic acid were found in all varieties except Great Northern beans. Lauric acid was found in Alaska peas. The list of component fatty acids of the phosphatides was similar to the triglycerides, except for the omission of linolenic acid in the phosphatides of the Great Northern, Michelite, Pinto, and lima beans. Palmitic acid constituted about 50% of the fatty acids in the phosphatides of the eight types of beans and peas studied. No significant simple correlation coefficients were obtained between triglyceride, phosphatide, or crude lipid content and the cooking time for the dry beans.

SUMMARY The possible sites of cysteine inhibition of enzymatic blackening using polyphenol oxidase from potatoes were studied. The initial site of cysteine inhibition of enzymatic blackening caused by tyrosine oxidation occurred at the oxidation of tyrosine to 3,4‐dihydroxyphenylalanine (dopa). Following the initial induction period, the oxygen uptake paralleled those treatments with no cysteine. Concentrations of cysteine (9.5 × 10‐3M) which inhibited tyrosine oxidation for 100 min did not inhibit dopa oxidation significantly. However, higher concentrations (1.9 × 10‐2M) inhibited dopa oxidation. Cysteine did not inhibit chlorogenic acid oxidation under the conditions of our study. Oxygen uptake with chlorogenic acid plus cysteine was higher than in the absence of cysteine. Cysteine concentrations which effectively inhibited tyrosine oxidation did not inhibit oxidation in the presence of tyrosine plus chlorogenic acid.