Cereal Chem 52:479 - 484.  |  VIEW ARTICLE
Protein Content and Amino Acid Composition of Maturing Buckwheat (Fagopyrum esculentum Moench).

Y. Pomeranz, H. G. Marshall, G. S. Robbins, and J. T. Gilbertson. Copyright 1975 by the American Association of Cereal Chemists, Inc. 

Kernel weight, hull:groat ratio, protein content, and amino acid composition were determined in two buckwheat cultivars harvested at four stages of maturity in 1971 and 1973. During maturation, a 3.0- to 5.6- fold increase in whole kernel weight was due to an up to eighteenfold increase in weight of the groat and correspondingly smaller (less than twofold) increase in hull weight. In the groat, the large increase in weight was accompanied by a decrease in protein concentration. In the hulls, concentrations of total nitrogenous compounds decreased considerably during maturation. In the hull proteins, the main changes in amino acids were increases in histidine and glycine. In the groat, contents of arginine increased and lysine, proline, alanine, and isoleucine decreased. Amino acid composition changes markedly in maturing cereals (e.g., wheat, barley, and oats), and legumes (e.g., peas), but is remarkably stable in maturing buckwheat. For limiting amino acids (e.g., lysine) and amino acids of storage proteins (e.g., glutamic acid), changes in buckwheat are intermediate between those of true cereals and legumes.