LAUSR

BACKGROUND Steamed bread is a popular staple food in China, and the significant regional differences of the microbiota in traditional starters make the flavor and quality of steamed bread highly variable along with long preparation times. Therefore, analyzing the microbial flora of traditional starters and their influences on the flavor and quality may help to solve the above problems, and it may also be conducive to potentially meet consumer needs and permit industrialization of this traditional fermented food. RESULTS One hundred thirty two fungal and 50 bacterial species were identified in 5 traditional starters, each with a different dominant genus. The fermentation properties of dough showed that total titratable acid, dough volume and gas production increased and the pH decreased with fermentation time. The traditional starters improved the quality of Chinese steamed bread (CSB) including the crumb structure, specific volume and sensory attributes. Thirty-three aroma compounds with a VIP (variable importance for predictive components) >1 were identified as characteristic aroma compounds. The correlations among the microbiota, aroma and qualities of CSB showed a greater contribution from the bacteria, which was consistent with the predictions of metabolic pathways in the sequenced genomes. CONCLUSION The quality of CSB fermented with traditional starters was improved induced by their different microbial profiles, and bacteria made a greater contribution than fungus to the aroma and qualities of CSB. This article is protected by copyright. All rights reserved.