[Correlation analysis of color change and Maillard reaction during processing of Gardeniae Fructus Praeparatus]

The chromaticity space parameters of the samples during the processing of Gardeniae Fructus Praeparatus(Jiaozhizi in Chinese herbal name, JZZ) were measured by the visual analyzer to analyze the color variation rule during the processing of JZZ, and the content changes of total reducing sugar, total amino acid and 5-hydroxymethylfurfural(5-HMF) related to Maillard reaction were measured. Pearson correlation analysis and linear regression analysis of the data were carried out by SPSS 24.0 software. The experimental results showed that the objective coloration of the samples in the processing of JZZ was basically consistent with the traditional subjective color judgment; the contents of total reducing sugar and total amino acids showed a decreasing trend during the processing of JZZ, and the content of 5-HMF showed an increasing trend, which was in line with Maillard reaction law. Pearson correlation analysis results showed that there was a significant correlation between the chromaticity space parameters L~*(lightness value), a~*(red green value), b~*(yellow blue value), E~*ab(total color value) and the contents of total reducing sugar, total amino acid and 5-HMF(P<0.01), among which the values of L~*, a~*, b~*, E~*ab were positively correlated with the contents of total reducing sugar and total amino acid, and negatively correlated with the contents of 5-HMF. The results of linear regression analysis also showed that these two were highly correlated. In this study, by establishing the correspondence relationship between the color change of JZZ processing and Maillard reactants, wecan not only provide a basis for the objective digital expression of subjective color of JZZ, but also provide a reference for explaining the processing mechanism of JZZ from a new perspective.