Analysis of volatile compounds in Xiangjiao baijiu from different storage containers and years based on HS-GC-IMS and DI-GC–MS

Abstract

The volatile compounds in 16 different storage containers and years of Xiangjiao Baijiu (XJBJ) were compared and analyzed via direct injection (DI) combined with gas chromatography–mass spectrometry (GC–MS) and headspace extraction (HS) coupled with gas chromatography-ion mobility spectrometry (HS-GC-IMS) for the first time. Through HS-GC-IMS analysis, it was found that the succession rules of 14 compounds such as furfural during aging process. A total of 60 compounds were identified using DI-GC–MS. Twenty-five of these compounds were further quantified, and 19 compounds had odor activity values (OAVs) > 1, which were important contributor to aroma of XJBJ. Among them, those with OAVs >1000 included ethyl hexanoate, ethyl octanoate, ethyl butanoate, and ethyl pentanoate. Combining the results of quantitative, OAVs and partial least squares-discriminant analysis (PLS-DA) revealed that 10 compounds such as ethyl octanoate were the important compounds that lead to the differences between different storage types of XJBJ.

Keywords

• Xiangjiao baijiu
• Volatile compounds
• Headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS)
• Direct injection-gas chromatography–mass spectrometry (DI-GC–MS)
• Odor activity values (OAVs)
• Partial least squares-discriminant analysis (PLS-DA)