Nutritive Value of Central American Beans. IV. The Essential Amino Acid Content of Samples of Black Beans, Red Beans, Rice Beans, and Cowpeas of Guatemalaa

摘要

SUMMARYThe rice bean (Phaseolus calcaratus), cowpea (Vigna sinensis), red bean, and three black bean (Phaseolus vulgaris) samples grown in Guatemala, were found to be fairly similar in chemical composition. Average percentage values were: moisture 14.5, protein 22.3, ether extract 1.3, ash 3.5, crude fiber 6.0, and carbohydrate 52.4. The range in amino acid content, expressed as mg of amino acid per gram of nitrogen, was: arginine 356‐528, histidine 159‐232, isoleucine 143‐339, leucine 189‐260, lysine 322‐544, total sulfur‐containing amino acids 80‐94, phenylalanine plus tyrosine 362‐471, tryptophan 52‐73, threonine 215‐348, and valine 191‐383. The cowpea sample was higher in lysine; the rice bean and red bean samples were higher in tryptophan. The isoleucine and valine contents were lower, and the leucine higher, in the red beans than in the other samples. When compared with the amino acid pattern of the FAO Reference Protein, methionine plus cystine was the most‐limiting amino acid, and leucine and tryptophan respectively the second‐ and third‐most limiting. All the samples contained high amounts of lysine, making beans a goo