Evaluating the Headspace Volatolome, Primary Metabolites, and Aroma Characteristics of Fermented with and .

Production of good primarily depends upon the selection of substrate materials and fermentative microflora, which together influence the characteristic flavor and aroma. Herein, we performed comparative metabolomic analyses of volatile organic compounds (VOCs) and primary metabolites for samples fermented individually with and . The VOCs and primary metabolites were analyzed using headspace solid phase microextraction (HS-SPME) followed by gas chromatography time-of-flight mass spectrometry (GC-TOF-MS). In particular, alcohols, ketones, and furans were mainly detected in -fermented (, BK), potentially due to the increased levels of lipid oxidation. A cheesy and rancid flavor was characteristic of , which is attributable to high content of typical 'off-flavor' compounds. Furthermore, the umami taste engendered by 2-methoxyphenol, (E,E)-2,4-decadienal, and glutamic acid was primarily detected in . Alternatively, malty flavor compounds (2-methylpropanal, 2-methylbutanal, 3-methylbutanal) and sweet flavor compounds (monosaccharides and maltol) were relatively abundant in -fermented (, AK). Hence, we argue that the VOC profile of is largely determined by the rational choice of inocula, which modifies the primary metabolomes in substrates, potentially shaping its volatolome as well as the aroma characteristics.