LAUSR

The aim of the study was to analyze the correlation between the key aroma compounds and gDNA copies of Bacillus natto during fermentation and maturation of natto. Solvent-assisted flavor evaporation (SAFE) techniques were employed to extract volatile organic compounds. Aroma compounds were separated and analyzed through gas chromatography-olfactometry-mass spectrometry (GC-MS/O) using DB-5 and DB-Wax capillary columns. Seventy-nine compounds were extracted and identified, including 17 ketones, 17 alcohols, 9 aldehydes, 6 acids, 7 esters, 8 pyrazines, 8 aromatics, and 7 others. Twenty-two compounds were identified as the key aroma compounds of natto by aroma extraction dilution analysis (AEDA). Pyrazines played a key role in the flavor of natto both during the fermentation and maturation. 2,5-Dimethylpyrazine, 2,3,5-trimethylpyrazine, 2,3,5,6-tetramethylpyrazine, and 2,3,5-methyl-6-ethylpyrazine contributed substantially to natto flavor. They presented significant positive and negative correlations with the gDNA copies of Bacillus natto during fermentation and maturation, respectively.