Amur breeding soybean varieties evaluation for lysine content

The aim of research is to assess the content of lysine, a valuable and important amino acid for food and feed purposes, in the composition of soybean protein in varieties bred at the All-Russian Soybean Research Institute in 2003-2020. Lysine is the first of the limiting amino acids that are required for the normal metabolism of proteins from food and feed. If this amino acid is not enough, then regardless of the amount of protein that enters the body, it will not be digested normally. The relatively high need for it (3-5 g per day for a person) makes it one of the most important essential amino acids. A high content of this amino acid is found in amaranth and legumes, especially soybeans. The main task of research is to determine the most suitable varieties for the creation of high-lysine food products and feed additives. Laboratory studies of the amino acid composition of soy protein were carried out in 2018-2020 in the testing laboratory of the Institute by the method of diffuse reflection of light in the infrared region of the spectrum on an IR-scanner model FOSS NIRSystems 5000. It was found that the content of lysine in the grain protein of soybeans of Amur varieties ranges from 6.0 to 6.3 %, which is significantly higher than in varieties of European Russian selection. All studied varieties of the Institute's breeding have a high amino acid index for lysine - from 109 to 113 %, which significantly exceeds the FAO/WHO standard. The highest rates for the content of this important and nutritious amino acid were noted for the early ripening variety Kruzhevnitsa (6.3 %). Such indicators make it possible to classify this variety as high-lysine and recommend it for the preparation of high-quality food products and feed additives of plant origin.