OENO IVAS 2019 banner
IVES 9 IVES Conference Series 9 OENO IVAS 9 OENO IVAS 2019 9 Grape and wine microorganisms: diversity and adaptation 9 Genetic causes of SO2 consumption in Saccharomyces cerevisiae

Genetic causes of SO2 consumption in Saccharomyces cerevisiae

Abstract

SO2 is used during winemaking for its anti-oxidative and anti-microbial properties. A high SO2 concentration in the wine has negative impacts by hiding wine aromas and delaying malolactic fermentation. SO2 concentration is also a source of health concerns and is therefore legally regulated. During the alcoholic fermentation SO2 can be produced or consumed by the yeast Saccharomyces cerevisiae with a high variability depending on the strain that accomplish the fermentation. The selection of industrial strains leaving less SO2 at the end of fermentation is therefore of great interest. 

In this study we implemented a QTL (Quantitative Trait Loci) mapping program to identify genetic factors that impact SO2 production by yeast during fermentation. This approach requires the study of a large progeny in segregation that must be characterized genetically and phenotypically. The establishment of a statistical link between genotype and phenotype allows the localization of QTLs that have an impact on the characters. 

Small-scale fermentations in 10 ml screw cap vessels coupled with robotized enzymatic allowed us to measure SO2 profile of several hundred individuals from two progenies. These two progenies were also genotyped by whole genome sequencing providing saturated genetic maps of thousands of markers. This experimental design led us to the identification of nine QTLs controlling SO2. Four of them present in MCH1, STR2 and SSU1 genes were molecularly validated. These alleles also show a pleiotropic effect with link between the production of SO2 and acetic acid. In the future, these new alleles can be used in cross breeding programs for the improvement of industrial strains.

DOI:

Publication date: June 10, 2020

Issue: OENO IVAS 2019

Type: Article

Authors

Emilien Peltier (1,2), Maria Martí Raga (1,3), Miguel Roncoroni (4), Vladimir Jiranek (5), Yves Gibon (4), Philippe Marullo (1,2)

(1) Unité de recherche Oenologie, EA 4577, USC 1366 INRA, ISVV, Université de Bordeaux, Bordeaux INP, F33882 Villenave d’Ornon France
(2) Biolaffort, Bordeaux, France
(3) Departament de Bioquímica i Biotecnologia, Facultat d’Enologia de Tarragona, Spain
(4) Wine Science Programme, University of Auckland, New Zealand
(5) Department of Wine and Food Science, University of Adelaide, Australia
(6) INRA, University of Bordeaux, UMR 1332 Fruit Biology and Pathology, Villenave d’Ornon, France

Contact the author

Keywords

Yeast, QTL mapping, SO2 

Tags

IVES Conference Series | OENO IVAS 2019

Citation

Related articles…

Laying footprints on a new path: proper accounting of biogenic fluxes makes viticulture carbon neutral

To limit the acceleration of global warming we need to reduce greenhouse gases emissions (GHG), making our production processes more carbon-efficient and optimizing absorptions.

Novel ATR-FTIR and UV-Vis spectral markers for assessing the Prooxidant/Antioxidant Balance (PAB) in white wines

The browning index (BI), based on the absorbance at 420 nm, is a common oxidation marker in white wines, typically measured after thermal stress (50–60 °C for 5 up to 12 days) in air-saturated wines.

High and extreme high temperature effects on shiraz berry composition 

Climate change is leading to a rise in average temperature and in the frequency and severity of heatwaves, and is already significantly disturbing grapevine phenology and berry composition. With the evolution of the weather of Australian grape growing regions that are already warm and hot, flavonoids, for which biosynthesis depends on bunch microclimate, are expected to be impacted. These compounds include anthocyanins and tannins which contribute substantially to grape and wine quality. The goals of this project were to determine if berry tannin accumulation is sensitive to high temperature and to enhance knowledge on upper temperature limits for viable wine production, in turn informing critical timing for mitigation strategies.

ASSESSING THE ROLE OF 27 KNOWN BITTER COMPOUNDS IN COMMERCIAL WHITE WINES COMBINING LC-MS QUANTIFICATION AND SENSORY ANALYSIS

The balance between the different flavours of a wine largely determines its perception and appreciation by the consumers. In white wines, sweetness and sourness are usually the two poles balancing the taste properties. The bitter flavour, on the other hand, is frequently associated with a loss of equilibrium and all white wines (dry and sweet, young and aged) are affected.
Several bitter compounds are already well-described in wines.

Modeling the suitability of Pinot Noir in Oregon’s Willamette Valley in a changing climate

Air temperature is the key driver of grapevine phenology and a significant environmental factor impacting yield and quality for a winegrape growing region. In this study the optimal downscaled CMIP5 ensemble for computing thegrowing season average temperature (GST) viticulture climate classification index was determined to spatially compute on a decadal basis predictions of the GST climate index and the grapevine sugar ripeness (GSR) model for Pinot Noir throughout the Willamette Valley (WV) American Viticultural Area (AVA). Forecasts for average temperature and a 220 g/L target sugar concentration level were computed using daily Localized Constructed Analogs (LOCA) downscaled CMIP5 historic and Representative Concentration Pathways (RCP) future climate projections of minimum and maximum daily temperature. We explore spatiotemporal trends of the GST climate classification index and Pinot Noir specific applications of the GSR phenology model for the WV AVA. Spatiotemporal computations of the GST climate index and Pinot Noir specific applications of the GSR model enable the opportunity to explore relationships between their computed values with one intent being to provide updated GST ranges that better align with current temperature-based modeling understanding of Pinot Noir grapevine phenology and the viticultural application of LOCA CMIP5 climate projections for the WV AVA. The Pinot Noir specific applications of the GSR model or the GST index with updated bounds indicate that the percent of the WV AVA area suitable for Pinot Noir production is currently at or near its peak value in the upper 80s to lower 90s of this century.