Project description:Rice is one of the main raw materials for Baijiu fermentation and plays an important role in the process of Baijiu brewing. Different varieties of rice may have different compositions of aroma substances in Baijiu due to different contents of physical and chemical components (amylopectin, tannin, fat, etc.), which may affect liquor quality. However, there is currently no systematic understanding of the differences in the types and contents of physicochemical components among different varieties of rice. This study mainly uses modern technological methods to conduct in-depth analysis and precise determination of the physicochemical components of different rice varieties, exploring the differences in physicochemical components of different rice varieties. This study will lay the foundation for the directional breeding of rice for liquor making, and strongly promote the Baijiu industry to accurately screen rice raw materials with higher quality and adaptability.
Project description:Gluten-containing grains cause adverse health effects in individuals with celiac disease. Fermentation of these grains results in gluten-derived polypeptides with largely uncharacterized sizes and sequences, which may still trigger an immune response. This research used N-terminal labeling mass spectrometry to characterize protein hydrolysates during each stage of bench-scale brewing, including malting, mashing, boiling, fermentation, and aging. Gluten hydrolysates from each brewing step were tracked and the immunotoxic potential was evaluated in silico. The results indicate that proteolysis and precipitation of gliadins occurring during brewing differ by protein region and brewing stage. The termini of gliadins were hydrolyzed throughout the entire brewing process, but the central regions remained relatively stable. Most hydrolysis occurred during malting, and most precipitation occurred during boiling. The addition of yeast yielded new cleavage sites but did not result in complete hydrolysis. Consistent detection of peptides within the clinically important regions of gliadin corroborated the hydrolytic resistance of this region. N-terminal labeling mass spectrometry served as a novel approach to track the fate of gliadin/gluten throughout bench-scale brewing. Consistently identified fragments could serve as improved targets for detection of hydrolyzed gluten in fermented products.