Study on the characteristics and nutritional properties of germinated highland barley treated by different thermal processing based on quasi-targeted metabolomics

This study investigated the effects of four thermal processing methods (microwave, baking, stir - frying, steaming) on germinated highland barley (GHB). It assessed the nutritional and physicochemical properties, as well as starch digestion characteristics of GHB, and conducted quasi-targeted metabolomic analysis. The findings indicate that thermal processing alters the nutrient composition and hydration properties of GHB while preserving the integrity of its crystal and functional group structures. Short-duration or low-temperature treatment (microwave and steaming) can effectively maintain the nutritional and bioactive components in GHB. Quasi-targeted metabolomics analysis identified 1605 different metabolites, including organic acids, phenylpropanoids and polyketides. Notably, caffeic acid, apigenin, chrysin, 3-hydroxyphenylacetic acid and 3-methoxytyramine emerged as markers with potential health benefits from the thermal processing of GHB. This study provides a scientific reference for selecting appropriate thermal processing methods for GHB.