Abstract: Solid-phase support-liquid-liquid extraction (SLE) technique and chiral cyclodextrin column were used to identify two enantiomers (optical isomers) of ethyl lactate and three enantiomers of 2, 3-butanediol in Baijiu. The internal standard curve was used for quantification. The results showed that the linear relationship of ethyl lactate and 2, 3-butanediol was good in certain ranges, the recovery rate in matrix samples was more than 80%, and the relative standard deviation was 1.34%-8.5%. The limits of detection (LODs) of D-ethyl lactate, L-ethyl lactate and S-2, 3-butanediol, R-2, 3-butanediol, meso-2, 3-butanediol were 64.32, 47.74, 62.70, 59.08 and 26.58μg/L, respectively. This method was used to detect six liquor samples of three flavor types. The results showed that the content and proportion of chiral enantiomers were different in six liquor samples, and S-2, 3-butanediol (right-handed) was isolated from liquor for the first time. Due to its high accuracy and good reproducibility, the method could be used for detection of chiral substances in liquor, and can provide a new idea for liquor quality monitoring, origin tracing and quality identification by chiral recognition.
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