Through sensory experiments, 171 aroma and taste descriptors for four representative brands of Jiangxiangxing Baijiu were selected and a flavor wheel for Jiangxiangxing Baijiu was developed. The aroma and taste of the samples were described and evaluated by means of quantitative description analysis (QDA) and electronic tongue. Using principal component analysis (PCA), partial least square-discriminant analysis (PLS-DA) and analysis of variance (ANOVA), 14 descriptors such as Jiang-aroma, Chen-aroma, Qu-aroma, and grain-aroma were selected to distinguish different brands of Jiangxiangxing Baijiu, and five descriptors such as Jiang-aroma, Qu-aroma, softness, fullness and harmony were selected to distinguish different grades of Jiangxiangxing Baijiu. The findings of this study not only provide powerful scientific data support for the new national standard for Jiangxiangxing Baijiu, but also help improve the stability of Baijiu quality and innovation in the development and design of Baijiu body, thereby promoting technological progress and enhancing market competitiveness in the Jiangxiangxing Baijiu industry.

Light-flavor Baijiu is one of the four basic aroma types of Baijiu, and the succession and metabolism of the microbial community during the fermentation process is closely related to physical and chemical factors. Fermentation temperature is one of the most important factors. In this study, the fermentation process of light-flavor Baijiu at two different initial temperatures, (7.5 ± 1.0) and (15.5 ± 1.0) ℃, was analyzed using Illumina MiSeq sequencing and gas chromatography-mass spectrometry (GC-MS). The results showed that there were significant differences (P < 0.05) in the acidity of fermented grains at different initial temperatures; higher initial temperatures caused a more rapid increase in the relative abundance of Lactobacillus and Saccharomyces in the fermented grains. A total of 62 volatile compounds were detected in the fermented grains, and 12 compounds were identified as important contributors to the differences in the sensory quality of the raw Baijiu. Lactobacillus and Saccharomyces were significantly positively correlated with ethyl acetate, ethyl lactate, ethyl 3-phenylpropionate, furfuryl alcohol, ethyl caprate, ethyl butyrate, isoamyl acetate, and isobutyl alcohol and were the key microorganisms contributing to the formation of differential compounds. The microbial community structure and volatile compound composition during the fermentation process of light-flavor Baijiu can be effectively regulated by changing the initial fermentation temperature. This study is of great value in guiding the quality control and management strategies during the fermentation process.

This study investigated the aroma-active compounds and compared the differences of three different grades of sesame-flavor Baijiu by headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-olfactometry-mass spectrometry (GC-O-MS). A total of 54 aroma-active compounds were detected. Principal component analysis showed that JZ1, JZ2, and JZ3 were well separated from each other. JZ1 as the premium-grade Baijiu had the highest aroma intensities, concentrations. According to aroma intensities and concentrations, dimethyl trisulfide, butanoic acid, phenylacetaldehyde, 2-furylmethanethiol, ethyl hexanoate, 2,6-dimethylpyrazine, etc. could be potentially applied as volatile makers to distinguish the three different grades of sesame-flavor Baijiu as their significant difference (P < 0.05) in three Baijiu samples. Roasted aroma had the significant difference (P < 0.05) in three sample base on aroma profiles. Meanwhile, 2-furylmethanethiol, 2,6-dimethylpyrazine were related to the roasted aroma, they may be had a significant contribution to the differences of three different grades of sesame-flavor Baijiu. This study has provided a comprehensive understanding of the differences of three different grades of sesame-flavor Baijiu.