Discrimination of Chinese Baijiu grades based on colorimetric sensor arrays

Food Sci Biotechnol. 2020 Apr 19;29(8):1037-1043. doi: 10.1007/s10068-020-00757-z. eCollection 2020 Aug.

Abstract

In this study, a novel colorimetric sensor array based on chemo dyes including porphyrins and pH indicators were developed to analyse the volatile organic compounds of Chinese Baijiu with different grades. Ethyl acetate, ethyl butyrate and ethyl caproate appeared by significantly different concentration in different Baijiu grades measuring by gas chromatography and mass spectrometry and they were chosen as characteristic volatile organic components. The olfactory visualization system based on colorimetric sensor arrays was used to identify different Baijiu grades. The data were processed by building the principle components analysis, linear discriminant analysis and K-nearest neighbor classification models with the results of sensory evaluation and olfactory visualization system. This work presents a new-style colorimetric sensor using sensitive chemo dyes which has significant potential in quantitative analysis of volatile organic compounds, afterwards identifying different grades of Baijiu.

Keywords: Baijiu grades; Colorimetric sensor; K-nearest neighbor classification; Linear discriminant analysis; Principle components analysis.