The difference of the interaction between phenolic compounds and protein with diverse polymerization degrees in different red wines was investigated to find out the key components of astringency for improving the wine-making process and selecting grape varieties. Using the different varieties of red wines as material, the phenolic substances of wine were divided into three parts by C18 solid phase extraction column: monophenols, oligomers and polymers. The contents of total phenols and total flavanols were determined. The interactions of different phenolics and protein were investigated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and fluorescent spectrometry. There were significant differences in total phenols and total flavanols contents in red wines. The contents of total phenols and total flavanols of phenolic fragments with different degrees of polymerization in red wines were as follows: monophenols < oligomer < polymer. The results of SDS-PAGE and fluorescence spectrometry showed that the effect of high polymers on the protein was the strongest, and the effects of monophenols and oligomers in different wines on the protein presented variance. The composition with different degrees of polymerization in the wine had different effects on the wine astringency. In the process of selecting grape varieties and improving the wine-making process, the control of the phenolic substance could be considered, especially for the regulation of the polymer.
