New Biotechnology for the Production of Phytocompounds from Secondary Products of Grain Processing

The present research features a new biotechnological approach for complex processing of secondary cereal products. The approach makes it possible to obtain new functional foods and ingredients, such as carbohydrate-protein concentrate, dietary fiber concentrates, biologically active substances, polyphenols, and xylo-oligosaccharides. The complex biotechnology involves oat bran biotransformation and includes chemical, hydrothermal, and enzymatic methods of extraction, which allows manufacturers to obtain functional ingredients with antioxidant and prebiotic properties. The concentrates obtained as a result of the study contained a significant amount of protein, hydrolysis products of polysaccharides (glucose, maltodextrins), and free polyphenols. The experiment produced concentrates of biologically active substances containing xylo-oligosaccharides and phenolic compounds. The content of polyphenols was 67% of the total amount in oat bran, protein – 6.9%, carbohydrates – 80.7% xylo-oligosaccharides whith prebiotic properties 35.3%–71.5%, and ash 11.3%. The obtained data indicated a high antioxidant activity of polyphenol extracts. The differences in antioxidant activity between various methods of extraction are associated primarily with the completeness of extraction and the stability of the extracted phenolic compounds. Ultrasonic treatment proved beneficial for the extraction kinetics and the polyphenol yield at the initial stage, with an increase in antioxidant properties. As for the antioxidant activity of polyphenol concentrate during storage, the research did not reveal changes for 8 months at a temperature of 20 ± 1°C and a relative humidity of 70 ± 5%. The study of the growth dynamics of Lactobacillus acidophilus and Bifi obacterium bifi um in media containing xylo-oligosaccharide concentrate confirmed the presence of prebiotic properties and their selectivity. The accumulation of biomass of prebiotic cultures occurred faster with the use of nutrient media with the use of xylo-oligosaccharide concentrate and lactulose, as compared with milk. Thus, the research confirmed the feasibility of biotechnology for transforming oat bran into functional ingredients, which makes it possible to use them in new technological solutions for products with bifidogenic properties.