AMINO ACID COMPOSITION OF GRAIN PROTEINS OF VARIETIES AND LINES OF SPRING SOFT WHEAT IN THE CONDITIONS OF NORTHERN KAZAKHSTAN

Abstract

The article is devoted to a comprehensive study of biochemical and technological quality indicators of grain and flour of promising varieties and lines of spring soft wheat grown in Northern Kazakhstan. The amino acid composition of grain from 28 breeding lines and 30 varieties of spring soft wheat has been studied. The protein content, quantity and quality of gluten, nature, weight of 1000 grains, and vitreousness were determined in the grain of the studied samples. After determining the number of essential and non-essential amino acids, the biological value of the protein was assessed by the amino acid score method. The physical properties of the dough were studied, the baking and color characteristics of bread were determined by the method of trial laboratory baking. The total amount of interchangeable and essential amino acids in the grain ranged from 3.37% to 4.41% and from 5.34% to 7.16%, respectively. The lines with a high content o  essential amino acids are highlighted 53/14 (4,41%), 29/13 (4,23%), 221/14 (4,02%), 256/14 (3,97%), 3/14 (3,80%), of interest for increasing the nutritional value of wheat grains. The limiting amino acids in the grain of the studied varieties are lysine (on average 74%), leucine and isoleucine (81%). The lines 53/14 (lysine - 85%, leucine and isoleucine - 92%), 147/14 (lysine - 87%, leucine and isoleucine - 91%), 221/14 (lysine - 85%, leucine and isoleucine - 90%) were identified with the most balanced amino acid composition. The Virgin 50 variety with the maximum amount of essential amino acids (4.05%) was noted. The amount of amino acids in grain and bread is determined, and a comparative characteristic is given. According to the correlation analysis, a very high relationship was found between lysine and phenylalanine (r = 0.98), leucine, isoleucine and valine (r = 0.96).