Study of Unpicked Grapes Valorization: A Natural Source of Polyphenolic Compounds and Evaluation of Their Antioxidant Capacity: A Natural Source of Polyphenolic Compounds and Evaluation of Their Antioxidant Capacity
Loading...
Identifiers
Publication date
2022-03-21
Advisors
Journal Title
Journal ISSN
Volume Title
Publisher
Citations
Export
Abstract
Every year great amounts of high-quality wine grapes are left on the vine unpicked, and consequently lost, to control the overproduction in wine areas with limited appellation production yield. In the context of circular bioeconomy, the valorization of these grapes as a potential source of natural antioxidants is of great interest. The study carried out is focused on the polyphenolic profile characterization of different unpicked grape varieties using the ultrasound-assisted extraction technique to extract the polyphenolic fractions. Moreover, the evaluation of the antioxidant capacity by several assays was carried out: oxygen radical absorbance capacity (ORAC), stability of 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), ferric reducing antioxidant capacity (FRAP), cupric reducing antioxidant capacity (CUPRAC) and stability of 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) radical (ABTS) assays. The results showed a strong relationship between total phenolic content and hydroxycinnamic acids (R2 = 0.9088) followed by flavan-3-ols (R2 = 0.8792) and tannins (R2 = 0.7705). The antioxidant capacity of the grapes was dependent on the total phenolic content. These results supply new information for a better understanding of the importance of giving an added value to the unpicked grapes due to their high content of polyphenols. These findings help the wine sector to consider the valorization of the unpicked grapes, classified as wastes, as an interesting source of natural antioxidants to be used as food supplements and with potential applications in the pharmaceutical industry.
Description
Publisher Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland.
Keywords
Unpicked grape , Polyphenols , Antioxidant capacity , Ultrasound-assisted extraction , Grape valorization , Unpicked grape , Polyphenols , Antioxidant capacity , Ultrasound-assisted extraction , Grape valorization , Nature and Landscape Conservation , Management, Monitoring, Policy and Law , Funding Info , This research received no external funding. , This research received no external funding.
Type
Citation
Elejalde , E , Villarán , M , Lopez-de-Armentia , I , Ramón , D , Murillo , R & Alonso , R 2022 , ' Study of Unpicked Grapes Valorization: A Natural Source of Polyphenolic Compounds and Evaluation of Their Antioxidant Capacity : A Natural Source of Polyphenolic Compounds and Evaluation of Their Antioxidant Capacity ' , Resources , vol. 11 , no. 3 , 33 , pp. 33 . https://doi.org/10.3390/resources11030033