Evaluation of biochemical composition of soy grain in comparative and varietal aspect

The goal of the research was to conduct a comparative analysis of the grain of new soybean varieties selected in the All-Russian Scientific Research Institute of Soybean (ARSRI of Soybean) for a number of indicators of biochemical composition. The research tasks were to study biochemical composition of soya bean, to conduct a comparative analysis according to its main indicators. The objects of the research were new soybean varieties selected by ARSRI of Soybean and grown on the selection experimental fields of the Institution in Sadovoe village, Tambov District, Amur region: Kruzhevnitsa, Zhuravushka, Nevesta, Kukhanna, Lebyodushka, Pepelina, Kitrossa, Sentyabrinka, Statnaya, Zolushka, Topaz and Charodeika. The sampling of the being studied varieties was carried out in the phase of full grain ripeness according to State Standard 17109-88, State Standard 13586.3-2015. The determination of biochemical composition of soya bean with a moisture content of 9-10 % was conducted in four-fold replication using “FOSSNIRSistem 5000” analyzer, “Cary 50 Scan” spectrophotometer (“Varian” company) with CaryWinUV software: oil-protein, amino acid, fatty acid compositions - in accordance with State Standard 32749-2014, trypsin-inhibitory activity (TIA) - State Standard 33427-2015. It was found that mainly all soybean varieties had average protein content of 35.61-38.68 % and oil content - 17.79-19.78 %. A negative strong correlation was found between the protein and oil content (r = - 0.80). TIA of soya grain ranged from 21.58-25.08 mg/g. Low content of methionine+cystine (1.53-1.99 %), significant intervarietal variation of histidine (4.87 %) and valine (1.67 %) were noted in the amino acid composition of soya protein. A wide range of variation of oleic acid - within 8.35 %, linoleic (ω-6) - 2.39 %, linolenic (ω-3) - 5.67 % was observed in the fatty acid composition. Optimal linoleic-linolenic ratio (ω-6: ω-3) from 4.6 : 1 to 10.4 : 1 was marked. The results of research give evidence of the varietal specificity of biochemical indicators of soya grain in the being studied varieties, corresponding to general characteristics of the food industry demands required of soy raw materials.