Saperavi Wine By-Products as a Sustainable Source of Bioactive Polyphenols: Phenolic Composition and Antioxidant Potential

Comparative Analysis of Fermented and Unfermented Grape Skins and Seeds from the Kakheti Region

Authors

DOI:

https://doi.org/10.66636/gmj.v1.i2.a121

Keywords:

Saperavi, Vitis vinifera, polyphenols, antioxidant activity, grape by-products, grape seeds, grape skins, circular bioeconomy, nutraceuticals

Abstract

Grape-derived polyphenols have gained increasing attention due to their antioxidant, anti-inflammatory, and cardioprotective properties, which are relevant in the prevention of cardiovascular and neurodegenerative diseases. This study investigates the phenolic composition and antioxidant activity of Saperavi (Vitis vinifera L.) winemaking by-products obtained from the Kakheti region of Georgia. Unfermented and fermented grape skins and seeds were analyzed for total phenols, flavonoids, catechins, leucoanthocyanins, and DPPH radical-scavenging activity. The results demonstrate that unfermented materials retain significantly higher concentrations of bioactive compounds compared to fermented residues, indicating substantial transfer of phenolics into the wine matrix during fermentation. Unfermented grape seeds exhibited the highest phenolic content, while grape skins showed strong antioxidant activity. These findings highlight the potential of Saperavi by-products as sustainable raw materials for the development of natural antioxidant formulations. The study supports the valorization of winemaking residues within a circular bioeconomy framework and their potential application in nutraceutical and functional food industries.

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Cover of the Georgian Medical Journal (GMJ), Volume 1, Issue 2 (2026), titled “Health Systems Performance and Quality of Care: Measurement, Improvement, and Outcomes,” with a blue world map background representing global health connectivity. Includes the themes “Quality, Safety, Results” and the publisher Public Health Institute of Georgia.

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Published

05/08/2026

How to Cite

Diasamidze, K., Kalandia, A., Jafaridze, I., & Vanidze, M. (2026). Saperavi Wine By-Products as a Sustainable Source of Bioactive Polyphenols: Phenolic Composition and Antioxidant Potential: Comparative Analysis of Fermented and Unfermented Grape Skins and Seeds from the Kakheti Region. Georgian Medical Journal, 1(2), 1–8. https://doi.org/10.66636/gmj.v1.i2.a121

Issue

Vol. 1 No. 2 (2026): Health Systems Performance and Quality of Care

Section

Original Research

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Copyright (c) 2026 Khatuna Diasamidze, Aleko Kalandia, Indira Jafaridze, Maia Vanidze

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