Study on the flavor of brown milk fermented by Lactobacillus paracasei K56 in different strain states

A comprehensive investigation of the differences in flavor profiles among different strains of fermented brown milk (FBM) is important to guide the improvement of the flavor quality of FBM. Seven samples were analyzed by dynamic headspace extraction (DHS) and gas chromatography–olfactometry–mass spectrometry (GC–O–MS), and a total of 73 odor compounds were identified. Key odor compounds including 3-methyl-1-butanol, ethyl acetate, linalool, furfuryl alcohol, 2-pentylfuran, hexanal, and 1-octen-3-ol, were screened by multivariate statistical analysis to reveal the flavor differences of FBM from different strains. 3-Methyl-1-butanol and ethyl acetate were found to be the key odor compounds distinguishing FBM by strain K56 from other strains, and the fermentation strains were found to be the key factors affecting the flavor of FBM compared to the fermentation substrate and fermentation process. This study provided a relatively systematic investigation of the flavor of FBM and could be used to monitor changes in odor components and sensory characteristics for product quality control.