Chemical and Electrochemical Assessment of Wine Lees Extracts Tested as Novel Antioxidant Additives in Model Wine

Abstract

Yeast derivatives are used in winemaking for a variety of purposes, including the protection of wines from oxidation. In this work, by the application of an autoclave extraction method, different fractions were obtained from red wine lees and a labgrown culture of the same yeast strain. Each extract was characterized for their protein, polysaccharide, glutathione, thiol, and polyphenol contents. The antioxidant activity was tested by adding each extract in a model wine enriched with catechin and saturated with oxygen. The presence of both wine lees and lab-grown yeast extracts delayed oxygen consumption when compared to the untreated control. This delay was confirmed by the development of a yellow color, which was lower in 5 out of 6 of the samples added with yeast/lees extracts. The electrochemical behavior of the samples also showed a greater resistance to oxidation, thus suggesting a protective role of the wine lees extracts against wine oxidative phenomena.

Optimized extraction technology of glutathione from ‘Haidao 86’ germ rice by response surface methodology

“…Natural glutathione was mainly extracted from plant seeds, yeast, and chicken blood, among which cereal germ was a good source of glutathione. The content of GSH from different sources was quite different, with 51.55 mg/100 g of glutathione from wheat germ (Li, Xu, & Dong, 2015 ), 145 mg/100 g from corn germ (Zare et al, 2023 ), 8.8213 mg/100 g from wine mud (De et al, 2023 ), and 29.94 mg/100 g from yeast (Roswag et al, 2022 ). In this study, the GSH content of HDGRP (up to 139.68 mg/100 g) was higher than that of wheat germ and yeast and slightly lower than that of corn germ.…”

“…GSH (often referred to as reduced glutathione) is an acidic peptide with an isoelectric point of 5.93. It was stable under acidic conditions (Zare et al, 2023 ) and soluble in polar solvents such as water, dilute alcohol, and dilute acid (De et al, 2023 ). The common extraction methods of GSH were formic acid, ethanol, sulfuric acid, hot water extraction, and other extraction methods (Altemimi et al, 2023 ; Chen et al, 2009 ; Li, Wang, & Tian, 2015 ; Wang et al, 2020 , 2021 ), and the content of seed germ could reach 100–1000 mg/100 g (Wang et al, 2021 ).…”

The effect of yeast autolysis on the composition of wine

“…Grapes are fruits with a high level of antioxidant activity [21]. However, after fermentation, phenolic compounds were lost, which are primarily responsible for antioxidant activity [22], [23]. It can be seen from Figures 7-9 that the with sludge variants had a higher decrease in antioxidant activity than the without sludge variants.…”