[Quality changes of Gardeniae Fructus Praeparatus processed by different frying methods: a color-component...

The chromatic values of the broken-fried and single-fried Gardeniae Fructus Praeparatus(GFP) were measured by the color analyzer to analyze the color variation rule, and the contents of 10 main components were determined by ultra-high performance liquid chromatography(UPLC). The multivariate statistical analysis, Pearson correlation analysis, and discriminant analysis were conducted to investigate the color and components of GFP samples. The experimental results revealed that L~*, a~*, b~*, and E~*ab decreased continuously during processing, and the color of samples gradually deepened. The trend and range of chromatic values during broken-frying and single-frying processes were basically identical. Gardenoside, crocin-Ⅰ(C-Ⅰ), and crocin-Ⅱ(C-Ⅱ) showed an obviously downward trend, while the contents of geniposidic acid and 5-hydroxymethylfurfural(5-HMF) increased significantly. Shanzhiside, deacetyl-asperulosidic acid methyl ester, and geniposide(G2) showed a downward trend. Scandoside methyl ester rose first and fell later. Genipin-1-O-gentiobioside(G1) went through a decrease-increase-decrease trend. The change trends of component contents during broken-frying and single-frying processes were generally consistent, but the change range was different. Among all the components, scandoside methyl ester and G1 showed obvious change. Because of different stir-frying time, the change rate of each component content in the process of broken-frying was higher than that in single-frying process. Additionally, geniposidic acid, gardenoside, scandoside methyl ester, C-Ⅰ, C-Ⅱ, and 5-HMF exhibited a higher correlation with apparent color. On the basis of above findings, the discriminant function of two frying processes was established, which could be applied to the discrimination of broken-fried and single-fried samples. This study analyzed the dynamic quality change rule of GFP during broken-frying and single-frying processes based on color-component correlation analysis, and found the two methods showed consistent change trend, yet with slight difference in the quality of samples. This study can provide data support for the processing of GFP.