LAUSR

BACKGROUND Oenological tannins are commercial natural products extracted from different botanical sources, which were widely reported as prominent contributors to wine quality. Research on wine quality affected by tannins extracts promoted the development of new oenological products with low cost and high accessibility. In the present study, the structure and concentration of tannin in polyphenols extracts, as well as their correlation with astringency and color of model wine was investigated by UV spectrophotometer, high-performance liquid chromatography (HPLC), fluorescence quenching, SDS-PAGE, colorimeter, and sensory evaluation. RESULTS Sixteen of 44 plants resources extracts were screened as wine oenological tannins, according to the total polyphenol and total flavanol, as well as the intensity of astringency and bitterness. Wherein, polyphenols extract from grape seeds and green tea were more effective in increasing the wine astringency than that of other plant tannins. CONCLUSION Total flavanol content and tannin activity were found a strong correlation wine astringency. Condensed tannins with mean degree of polymerization also exhibited strong color stability, and the concentrations of EGC are associated with a* value, a negative qualitative factor for wine color. This work provides new clues of developing low-cost and highly accessible sources of polyphenol extracts and is supposed to lay a theoretical foundation for the development of the oenological product. This article is protected by copyright. All rights reserved.