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Updated: Oct 12, 2025
A Generalized Method for Determining Free Soluble Phenolic Acid Composition and Antioxidant Capacity of Cereals and Legumes
Published on: June 10, 2022
Tocopherol contents and antioxidant activity in grape pomace after fermentation and alcohol distillation
Tamar Goloshvili1, Maia Akhalkatsi1, Gulnara Badridze1
1Institute of Botany, Plant Physiology and Genetic Resources, Ilia State University, Tbilisi, Georgia. tamar.goloshvili.1@iliauni.edu.ge.
Abstract:
The wine industry in Georgia produces vast amounts of grape pomace that is currently mostly wasted, while only a minor amount is used for distilling alcohol. The study was carried out on the grape pomace from the three most widely used grapevine sorts (Vitis vinifera var. Rkatsiteli, V. vinifera var. Saperavi, V. labrusca var. Isabella) in Georgia, and quantities of tocopherols and antioxidants were evaluated. The antioxidant activity was assessed by diphenyl-picrylhydrazyl (DPPH) and measurement of visible light absorption at 515 nm, and tocopherol was measured by absorption at 470 nm via a spectrophotometer. The results indicated that the grape pomace contains considerable tocopherols and antioxidant activity. However, the antioxidant activity had slightly been decreased. These results suggest that grape pomace can be an economically attractive resource for the pharmaceutical and food industries. Utilization of grape pomace for producing pharmaceutical and cosmetic goods with tocopherol and antioxidants can solve two problems: it can recycle waste and develop new profitable businesses in biotechnology.
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