Physicochemical properties of whole grain foxtail millet sourdough and steamed bread quality: Co-fermentation of lactic acid bacteria and yeast in whole grain fermented foods

Four strains of lactic acid bacteria (LAB) were selected to explore the physicochemical properties of whole grain foxtail millet (Setaria italica) sourdough and steamed bread quality. Both sourdough properties and steamed bread qualities were determined and compared. The results showed that LAB fermentation released bioactive polyphenol compounds. The pasting properties (PV, BD, FV, SB) decreased. T21 and T23 migrated to semi-bound water T22 and reduced the rheological G′ and G″ during the fermentation process (p < 0.05). LAB fermentation can significantly improve the steamed bread texture characteristics, and enrich the aroma of volatile compounds, especially esters, hydrocarbons, and others. The endogenous metabolites 2-methoxy-4-vinylphenol and 2,4-di-tert-butylphenol were found in the flavor profile and may play a functional effect. These results indicated that the LAB fermentation for whole grain foxtail millet functional steamed bread was practical and useful, which may lead to future innovations in the area of whole grain functional products.