DETERMINATION OF THE PROTEIN-QUALITY OF 3 NEW NORTHERN ADAPTED CULTIVARS OF COMMON AND MISO TYPE SOYBEANS BY AMINO-ACID-ANALYSIS

The total protein and amino acid contents of three new northern adapte d soybean cultivars, namely Apache, Baron, and a mise type Maple Belie and its older male recurrent parent Evans, were compared as potential ly useful indices for assessing their protein quality from their FAO/W HO amino acid scoring pattern. The total protein contents, although si milar, were statistically significantly different (P > 0.05), varying from 30.1% in Baron to 31.2% in Evans, 32.3% in Apache, and 31.5% in M aple Belie. All four soybean cultivars contained an excellent balance of essential amino acids (EAA), i.e., EAA(9) = 46-46.6% compared to th e FAO/WHO reference protein pattern value of 33.9% for a 2-5-year-old child. All were limited only in methionine, and to a lesser extent in isoleucine and valine, and had a protein digestibility corrected amino acid score of 91% compared to the values obtained for hen's whole egg (97%). These results indicate that an accurate calculation of protein quality of soybean seeds and other legumes can be made from their amin o acid composition.