Macrowine 2021
IVES 9 IVES Conference Series 9 Phytosterols and ergosterol role during wine alcoholic fermentation for 27 Saccharomyces cerevisiae strains

Phytosterols and ergosterol role during wine alcoholic fermentation for 27 Saccharomyces cerevisiae strains

Abstract

Sterols are a class of the eukaryotic lipidome that is essential for the maintenance of the cell membrane integrity and their good functionality (Daum et al., 1998). During alcoholic fermentation, they ensure yeast growth, metabolism and viability, as well as resistance to osmotic stress and ethanol inhibition (Mannazzu et al., 2008). Musts clarified in excess lead to the loss of solid particles rich in sterols, resulting in sluggish and stuck fermentations (Casalta et al., 2013). Two sterol sources can support yeasts to adapt to fermentation stress conditions: ergosterol, produced by yeast in aerobic conditions, and phytosterols, plant sterols found in grape musts imported by yeasts in the absence of oxygen (Nes, 1987). Little is known about the physiological impact of the assimilation of phytosterols in comparison to ergosterol and the influence of sterol nature on fermentation kinetics parameters. Moreover, studies done until today analyzed a limited number of yeasts strains. For this reason, the aim of this work is to compare the fermentation performances of 27 Saccharomyces cerevisiae strains with phytosterols and ergosterol on two conditions: sterol stress (sterol starvation) and osmotic stress (the most common stress during fermentation due to high concentrations of sugars).Experiments were performed in 300 mL fermenters without oxygen. Fermentation kinetics were monitored continuously through CO2 production in order to obtain parameters, such as the maximum fermentation rate (Vmax) or total CO2 production. Cell count and cell viability were measured around 80% of fermentation progress. Central carbon metabolism (CCM) metabolites (acetate, glycerol, succinate and residual sugars) were quantified at the end of fermentation.Principal Component Analysis with biological, kinetic and CCM variables revealed the huge phenotype diversity of strains in this study. Analysis of variance (ANOVA) indicated that both the strain and the nature of sterol explained the differences on yeast performances in fermentation. It should be noted that cellular viability is a key parameter in both sterol and osmotic stress. Indeed, strains with a high viability at the end of the fermentation finished fermenting earlier. Finally, ergosterol allowed a better completion of fermentation in both stress conditions tested.These results highlighted the role of sterols in wine alcoholic fermentation to ensure yeast growth and avoid sluggish or stuck fermentations. Interestingly, sterol nature affected yeast viability, biomass, kinetics parameters and biosynthesis of CCM metabolites

DOI:

Publication date: September 7, 2021

Issue: Macrowine 2021

Type: Article

Authors

Giovana Girardi Piva 

SPO, Univ Montpellier, INRAE, Institut Agro, Montpellier, France,Jean-Roch MOURET (SPO, Univ Montpellier, INRAE, Institut Agro, Montpellier, France)  Virginie GALEOTE (SPO, Univ Montpellier, INRAE, Institut Agro, Montpellier, France) Jean-Luc LEGRAS (SPO, Univ Montpellier, INRAE, Institut Agro, Montpellier, France) Erick CASALTA (SPO, Univ Montpellier, INRAE, Institut Agro, Montpellier, France) Anne ORTIZ-JULIEN (Lallemand SAS, Blagnac, France)

Contact the author

Keywords

wine yeast, sterol starvation, osmotic stress, yeast membrane, alcoholic fermentation

Citation

Related articles…

Elaboration des cartes conseils pour une gestion du terroir à l’échelle parcellaire: utilisation d’algorithmes bases sur des paramètres physiques du milieu naturel

The “Anjou Terroirs” programme aims at bringing the necessary scientific basis for a ratio­nal and reasoned exploitation of the technical itinerary of the terroir. The scale study is 1/12500. For the mapping, many parameters, such as the granulometry or the depth of soil are observed to each point of caracterisation.

Développement de l’appareil végétatif et maturation du raisin sur quatre sols de Pomerol en 1995

The Pomerol vineyard, located 35 km east of Bordeaux, covers around 800 ha on the left bank of the Isle. There is a system of fluvial terraces with more or less coarse gravel and pebble spreading, resting on a Tertiary substratum ranging from the Middle to Upper Eocene to the Lower Oligocene (Dubreuilh, 1993). This interweaving of terraces of varying thickness results in a brutal superposition of differentiated materials which give rise to various types of soil. Several site studies in this sector of the Libounais show significant morphological and analytical differences from one point to another (Guilloux et al ., 1978; Duteau, 1982; Van Leeuwen et al.., 1989). The distribution of the soils of the Pomerol vineyard was studied and resulted in a cartography at 1/25000th (Merouge, 1995).

Grape pomace, an active ingredient at the intestinal level: Updated evidence

Grape pomace (GP) is a winemaking by-product particularly rich in (poly)phenols and dietary fiber, which are the main active compounds responsible for its health-promoting effects. GP-derived products have been proposed to manage cardiovascular risk factors, including endothelial dysfunction, inflammation, hypertension, hyperglycemia, and obesity. Studies on the potential impact of GP on gut health are much more recent. However, it is suggested that, to some extent, this activity of GP as a cardiometabolic health-promoting ingredient would begin in the gastrointestinal tract as GP components (i.e., (poly)phenols and fiber) undergo extensive catabolism, mainly by the action of the intestinal microbiota, that gives rise to low-molecular-weight bioactive compounds that can be absorbed and utilized by the body.

Physiological and growth reaction of Shiraz/101-14 Mgt to row orientation and soil water status

Advanced knowledge on grapevine row orientation is required to improve establishment, management and outcomes of vineyards on terroirs with different environmental conditions (climate, soil, topography) and in view of a future change to more extreme climatic conditions. The purpose of this study was to determine the combined effect of row orientation, plant water status and ripeness level on the physiological and viticultural reaction of Shiraz/101-14 Mgt.

Polyphenol content of cork granulates at different steps of the manufacturing process of microagglomerated stoppers treated with supercritical CO2 used for wine bottling

The wine closure industry is mainly divided into three categories: screw caps, synthetic closures, and cork-based closures. Among this latter, microagglomerated cork stoppers treated with supercritical CO2 are now widely used, especially to avoid cork taint contaminations[1]. They are designed with cork granules obtained from cork offcuts of the punching process during the natural cork stoppers production. A previous study[2] showed that these stoppers released fewer polyphenols in 12 % (v/v) hydroalcoholic solution than natural cork stoppers.