Flavor Substances and Harzard Components in Luzhou Strong-aroma Baijiu Using Triticum aestivum L. ZN168 and Glutinous sorghum

To find potential brewing ingredients for Luzhou strong-aroma Baijiu, two Baijiu samples were fermented using Glutinous sorghum (GS) and its mixture with Triticum aestivum L. ZN168 (MGZ) in the ratio of 2:8 (w:w), and their flavor substances and harzard components were tested using headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME-GC-MS). The results showed that the proteins, polyphenols and anthocyanins contents in GS and MGZ were measured to show no significant difference (P>0.05), while the pectins contents of MGZ were down by 9.7% compared with GS. And compared with GS Baijiu, the total ester contents and the total acid contents of MGZ Baijiu were slumped by 7.9% and rising by 8.3% respectively, but both of them satisfied the national standards of superior Baijiu products in China. Meanwhile, being characteristic of high ethyl hexanoate contents, GS Baijiu and MGZ Baijiu both showed typical flavors of strong-aroma Baijiu. In two Baijiu samples, totally 102 volatile components were detected, identified and quantified, and 26 substances were found to contribute to the formation of flavor differences between the two Baijiu samples, using orthogonal partial least-squares discrimination analysis (OPLS-DA) and odor activity values (OAV) analysis. Compared with GS Baijiu, MGZ Baijiu had higher OAVs of middle- and long-chain fatty acid esters, fatty acids and alcohols, and its methanol and ethyl carbamate contents were fell by 20.6% and 39.9% separately, showing good safety with fill-bodied flavor, rich and mellow taste. These findings suggested that ZN168 could be a potential fermentation material for strong-aroma Chinese Baijiu.