Objective By systematically analyzing the polyphenolic composition content, astringency intensity, astringency mechanism, and their inherent correlations in Hezi (Chebulae Fructus, CF) pieces with different comminution degrees, this study aims to lay a foundation for its further development and research. Methods The CF was processed into six granule sizes (original granule, extra large granule, large granule, median granule, small granule, fine powder) for sampling. HPLC was employed to quantify the contents of chebulagic acid, gallic acid, chebulinic acid, ellagic acid, corilagin, and 1,3,6-tri-O-galloyl-β-D-glucose. The main chemical composition groups and differences of six kinds of particle size CF samples were analyzed by fingerprint. The astringency intensity of the samples was sensorially evaluated using a visual analogue scale (VAS). These data were utilized to analyze the correlations among comminution degree, polyphenolic composition, and astringency intensity. Furthermore, SDS-PAGE technology was applied to elucidate the underlying astringency mechanism through the protein interaction. Results The total content of six kinds of polyphenolic components displayed significant variation across different granule sizes in the following descending order: median granule > extra large granule > fine powder > large granule > small granule > original granule. The results of fingerprint analysis showed that the main chemical composition groups of the six samples were basically the same. Sensory evaluation revealed that different comminution degrees considerably influenced the perceived astringency intensity, which decreased sequentially as: fine powder > small granule > median granule > large granule > extra large granule > original granule. Correlation analysis identified gallic acid and corilagin as key variables linking comminution degree with astringency perception. SDS-PAGE confirmed that the astringency mechanism primarily involves binding interactions between polyphenolic components and salivary proteins, with the fine powder demonstrating the strongest protein-binding capacity. Conclusion Comminution degree serves as a critical processing parameter governing the dissolution of polyphenolic components and astringency intensity in CF. The sample with a particle size of 4.75—6.70 mm demonstrated the highest content of polyphenolic compounds, whereas the sample with a particle size of 0.15—0.18 mm elicited the most intense perception of astringency. Processing CF to a median granule size (4.75—6.70 mm) is therefore identified as the optimal strategy for balancing polyphenolic component dissolution and oral compliance. This study provides key scientific evidence to support the standardization of CF processing techniques and related product development.

Chebulae Fructus  /  comminution degree  /  polyphenolic components  /  astringency  /  correlation  /  HPLC  /  chebulagic acid  /  gallic acid  /  chebulinic acid  /  ellagic acid  /  corilagin  /  1,3,6-tri-O-galloyl-β-D-glucose  /  SDS-PAGE technology