Soybean processing by-products as a promising raw material for obtaining valuable substances

This review summarizes information published in recent years on methods of extraction of valuable substances from by-products of soybean processing. The three main products derived from soybean processing are: soy molasses, soybean meal and soy whey. In recent years, interest in soybean processing waste has grown significantly, as these products are rich in isoflavones, proteins and carbohydrates, which opens great potential for their processing. In this article, we focused on various methods for extraction of beneficial compounds from soy by-products. Nowadays, most scientists have focused on the extraction of isoflavones, compounds that have anticancer, antidiabetic, antiallergic effects. Because conventional extraction methods are expensive, time consuming, and use toxic, volatile, and highly flammable solvents, the global community is now moving toward to green extraction methods. Extraction with natural deep eutectic solvents (NADES) is presented as the most promising, since it does not have the disadvantages outlined above. However, to extract the maximum amount of isoflavones, molasses should be pre-treated with β-glucosidase to increase the yield of aglycone forms of isoflavones. Soybean by-products are a vast and under-researched topic. Research in the field of industrial waste disposal will solve problems not only with the environmental but will also affect the economic performance of manufacturing enterprises.