Comparative Metabolomic Analysis of Moromi Fermented Using Different Strains.

() is an important starter in the fermentation of koji and moromi. However, the effect of different strains on the quality of moromi has rarely been studied. For this reason, this study analyzed the physicochemical properties, enzyme activity, sensory quality, and metabolite profiles of moromi samples fermented using two strains ( KCCM12012P (moromi-1) and KCCM12804P (moromi-2)), which were newly isolated from fermented soy foods, and compared them to those of a commercialized strain (control). Amino-type nitrogen contents of moromi-1 and moromi-2 samples were higher than that of control moromi, and their amylase and protease activities were also higher. Moreover, metabolite profiles of moromi were significantly altered according to strains. In particular, the levels of many amino acids, peptides, nucleotides, and acidic compounds were altered, which resulted in changes in the sensory quality of moromi. Although volatile compounds were not investigated, the results suggested that the quality of moromi was significantly different for newly isolated strains, especially KCCM12804P, and they were superior to the commercial strain in terms of taste-related substances. Therefore, these strains could be used as good starters to produce moromi and soy sauce with good sensory quality.