Integration of E-tongue, GC-IMS and chemometrics for unraveling the disparities in volatile profiles of optimized jujube craft beers.

Jujube, possessing a delightful flavor and unique nutritional value, is suitable as an adjunct in brewing jujube craft beer. In this research, through the optimization of brewing conditions, the E-tongue, gas chromatography-ion mobility spectrometry (GC-IMS) coupled with chemometrics were adopted to conduct the analysis of the differences in the contents of volatile organic compounds (VOCs) between jujube craft beer and non-jujube craft beer. Notably, the ANS and CTS sensors of the E-tongue were capable of clearly distinguishing the aroma differences among various varieties. By integrating orthogonal partial least squares discriminant analysis (OPLS-DA) and relative odor activity value (ROAV), four key volatile compounds were successfully identified. Furthermore, through the construction of weighted gene co-expression network analysis (WGCNA), two modules and six hub volatile organic compounds were identified within the samples. The findings revealed that the optimal brewing process for jujube craft beer was as follows: the addition amount of jujube was 12 %, the addition amount of yeast was 0.5 g/L, and the fermentation temperature was 18 °C. The contents of these key VOCs were significantly distinct from those of non-jujube craft beer, and they exerted a significant influence on presenting the flavor of jujube craft beer.