[Rapid identification of honey-processing degree of Astragali Radix based on intelligent sensory technology and...

To analyze the differences and dynamic changes in the color, odor, and major chemical components of Astragali Radix during honey processing, this study used a CM-5 spectrophotometer and Hercules NEO ultra-fast gas phase electronic nose for analysis. High performance liquid chromatography was employed to determine the content of calycosin, calycosin-7-glucoside, formononetin, and ononin in the Astragali Radix decoction pieces processed with honey to different degrees. Multivariate statistical analyses including partial least squares-discriminant analysis(PLS-DA), orthogonal partial least squares-discriminant analysis(OPLS-DA), differential factor analysis(DFA), and Bayesian discriminant analysis were adopted to differentiate the Astragali Radix decoction pieces processed with honey to different degrees and evaluate the correlations between visual characteristics and chemical composition. The results showed that chromatic values c~*, b~*, and L~* were the main color difference variables distinguishing raw and honey-processed Astragali Radix decoction pieces. The reference ranges for the chromatic values of raw and honey-processed Astragali Radix decoction pieces were determined based on these key color parameters. A total of 18 odor components were identified in Astragali Radix during the honey-processing process, with cyclohexane and dimethyl sulfoxide identified as odor markers for distinguishing Astragali Radix decoction pieces with different honey-processing degrees. The content of calycosin had a significant correlation with that of 2-methylfuran and delta-nonalactone, two odor components. This study successfully and rapidly differentiated the Astragali Radix decoction pieces processed with honey to different degrees, providing a reference for the quality control and the quality evaluation of Astragali Radix decoction pieces based on the appearance traits during the process of honey processing.