IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Valorization of wine lees for oenological interest by eco-responsible processes

Valorization of wine lees for oenological interest by eco-responsible processes

Abstract

Wine lees are the second most important wine by-product in terms of quantity after grape stalk and marc. During aging on lees, it is well known that wine lees yield compounds that act as antioxydant. However the chemical nature of the compounds involved in this behavior (except polyphenols and glutathione) has not yet been totally elucidated. The scarce knowledge of wine lees composition and their potential exploitation make them a promising candidate to obtain new antioxidant products to be used in winemaking. In this study, an eco-sustainable approach to obtain lees extracts exhibiting antioxidant capacity is proposed. Such extracts could be used in a global enological strategy of sulfites level reduction.

During this work, lees extraction has been carried out with conventional solvent and subcritical water extraction. The solid/liquid ratio and the influence of extraction duration were studied for each solvent. The total composition of lees extracts was assessed. Proteins, lipids, polysaccharides, polyphenols, and glutathione analyses were performed by spectrophotometry and HPLC. Antioxidant capacity of each extracts was evaluated by three methods: the ability of antioxidants to scavenge a radical by DPPH, ferric reducing antioxidant power by FRAP and Oxygen Consumption rate (OCR) by direct oxygen consumption measurement.
Results show an important effect of operational conditions, solvent and matrice on the diversity of extracts in terms of composition and bioactivity. For the first time, an eco-sustainable process has been proposed for the valorization of white wine lees to obtain extracts with high antioxidant activity. The extracts antioxidant capacity is promising to their target application in vinification as well as in food industry in order to reduce doses of sulfites.

DOI:

Publication date: June 24, 2022

Issue: IVAS 2022

Type: Poster

Authors

Poulain Benjamin1 and Nioi Claudia1

1Université de Bordeaux, Unité de Recherche Œnologie EA 4577

Contact the author

Keywords

Wine lees, By-product, antioxydant, extraction

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Understanding sweetness of dry wines: first evidence of astilbin isomers in red wines and quantitation in a one-century range of vintages

The gustatory balance of wines relies on sweetness, bitterness and sourness. In dry wines, sweetness does not result from the presence of residual sugar as in sweet wines, but is due to other non-volatile compounds. Such taste-active compounds are released during winemaking, by grapes, yeasts or oak wood and belong numerous chemical families [1]. Beyond this diversity, stereochemistry of molecules can also influence their sensory properties [2]. However, the molecular determinants associated with this taste have only been partially elucidated. Astilbin (2R, 3R) was recently reported to contribute to wine sweetness [3]. As its aglycon contains two stereogenic centers, three other stereoisomers may be present: neoisoastilbin (2S, 3R), isoastilbin (2R, 3S), and neoastilbin (2S, 3S). These compounds have already been observed in natural products, but never in wine. This work aimed at assaying their presence for the first time in wines as well as their taste properties.The isomers were synthesized from astilbin and purified by semi-preparative HPLC.

Variability of Constitutive Stilbenoid Levels and Profiles in Grape Canes (Vitis spp.) depending on Genetic and Environmental Factors

Grape cane is a viticultural by-product that is currently underused or not used at all. Therefore, it bears a high potential for valorization due to the presence of anti-microbially active stilbenoids, being biologically relevant for plant defense. These compounds are highly interesting for applications in the agricultural sector as well as for the food and feed industry.

Yield prediction assessment before bloom and at veraison in a cv. Airén high yielding vineyard in Toledo (La Mancha, Spain)

Anticipation in the possible responses of grapevines to environmental variations is key to adjust field work in view of a more effective management. This idea has been the driving force behind the current work, which seeks to understand the interaction patterns of the vine with its habitat throughout the growing cycle.

Effect of irrigation in cover cropping vineyards

Cover cropping in vineyard is a sustainable and alternative soil management system to conventional tillage that is gaining more and more importance among winegrowers and is being promoted, among other organizations, by the European Union through the eco-schemes of the Common Agricultural Policy.
However, the use of cover crops in Mediterranean viticultural environments is conditioned, to a large extent, by the availability of irrigation water which, in a context of global warming like the one we are experiencing, must be adjusted to savings strategies, supplying to the vine only what it needs in each moment.

Distinctive flavour or taint? The case of smoky characters in wine

Forest fires in the vicinity of vineyards have significantly increased in the last decade and are a concern for grapegrowers and winemakers in many wine producing countries. The fires cause smoke drift throughout vineyards which cannot be avoided and may result in the production of wines described as ‘smoke tainted’. Such wines are characterized by undesirable sensory characters described as ‘smoky’, ‘burnt’, ‘ash’ aromas and flavours, and also may cause a lingering, unpleasant ashy aftertaste [1; 2].