Macrowine 2021
IVES 9 IVES Conference Series 9 The future of DMS precursors during alcoholic fermentation: impact of yeast assimilable nitrogen levels on the contents of DMSp in young wines

The future of DMS precursors during alcoholic fermentation: impact of yeast assimilable nitrogen levels on the contents of DMSp in young wines

Abstract

Some red wines develop a “bouquet” during ageing. This complex aroma is linked to quality by wine tasters1. The presence of dimethylsulfide (DMS) in those wines is implicated in the expression of “bouquet typicity”2. DMS is a result of the hydrolysis of its precursors. Several molecules, including S-methylmethionine, could constitute the precursors of DMS3. DMS can be liberated by alkaline hydrolysis and quantified by SPME-GC-MS4. The releasable DMS is designated by “DMSp”. The DMSp levels in grapes are 20 to 30 times higher than those observed in young wines5. Our question is : “What happens during the stages of fermentation?”First, DMSp levels were studied during a small-scale winemaking process and were measured in musts, in wine after alcoholic fermentation (AF) and after malolactic fermentation (MLF). Then, to understand the mechanism of the DMSp degradation, synthetic must was used with various levels of YAN and different pools of inorganic and organic nitrogen such as amino acids. Synthetic musts were supplemented by one of the known DMS precursor (S-methylmethionine), inoculated with S. cerevisiae and the fermentations were monitored by evaluating CO2 evolution.During AF, around 90% of DMSp is degraded by the action of yeast. The MLF consumed a little DMSp but it is negligible compared to AF. The link between DMSp and nitrogen would generate a variable consumption of DMSp during AF. Then, DMSp is consumed at the beginning of alcoholic fermentation during the yeast growth step and the level of consumption depends of the constitution of YAN. The several pools of nitrogen substances of YAN tested shows various results about the consumption or conservation of DMSp during AF.Finally, the assays in laboratory to try to control DMSp levels in young wine will help the winemakers to keep the ageing potential of red wine and maintain a high quality of wine.

DOI:

Publication date: September 14, 2021

Issue: Macrowine 2021

Type: Article

Authors

Justine Laboyrie

University of Bordeaux, ISVV, EA 4577, INRA, USC 1366 OENOLOGIE, 33140 Villenave d’Ornon, France,Marina Bely, University of Bordeaux, ISVV, EA 4577, INRA, USC 1366 OENOLOGIE, 33140 Villenave d’Ornon, France Nicolas Le Menn, University of Bordeaux, ISVV, EA 4577, INRA, USC 1366 OENOLOGIE, 33140 Villenave d’Ornon, France Stéphanie Marchand, University of Bordeaux, ISVV, EA 4577, INRA, USC 1366 OENOLOGIE, 33140 Villenave d’Ornon, France

Contact the author

Keywords

wine ageing potential, dimethylsulfide, s-methylmethionine, alcoholic fermentation, yeast assimilable nitrogen

Citation

Related articles…

La haie bocagère comme critère de zonage à l’échelle parcellaire

In the French AOCs, the production area of ​​the raw material can be subject to plot delimitation based on criteria of physical environment and use. On the other hand, many environmental zonings are developing and the AOCs are called upon include provisions relating to these concerns. Hedges, through their effects on local changes in the regional climate and on functional biodiversity, can impact the functioning of vines and orchards. It is for this reason that their consideration as a delimitation criterion is envisaged.

Read More

Effects of different organic amendments on soil, vine, grape and wine, in a long-term field experiment in Chinon vineyard (France)

In a long-term experiment carried out in Chinon vineyard (37, France) during 23 years, the effects of several organic amendments were studied on soil, vine, grapes and wine. Four main treatments were compared on a calcareous sandy soil: control without organic amendment, dry crushed pruning wood at 2.1.t-1.ha-1.year-1 (D1), cow manure at 10 t-1. ha-1.year-1 (D1) and cow manure applied at 20 t-1.ha-1.year-1 (D2). D1 levels were calculated to fill the annual humus losses by mineralization.

Read More

Satellite imagery : a tool for large scale vineyard management

Remote sensing, using Near Infra Red wavelength, can characterize within-vineyard variability using vegetation index. Between 2007 and 2009, a study was led on the vineyards of a cooperative winery, in Fitou area (France) aiming at characterizing vineyard oenological potential. A vegetation index, green leaf cover, developed on crops (wheat, rice, corn…) was implemented on vineyards.

Read More

Influence of the type of tanks employed for winemaking on red wine phenolic composition

The grape maturation process is being affected by the consequences of global climate change and, as a result, there is a gap at harvest time between the technological maturity of grapes (mostly the concentration of sugar and acids) and its phenolic quality. Due to this gap, the wines elaborated using those grapes show a non-adequate phenolic composition, which results in defects on its color and astringency characteristics. Astringency is mainly related to the salivary protein precipitation because of the interaction not only with wine flavanols but also with other wine phenolics, such as flavonols or different pigments.

Read More

Harvest dates – temperature relationships and thermal requirements of winegrape varieties in Greece: observed and future climate responses

Air temperature is arguably one of the most decisive factors for winegrape varieties developmental cycle, ripening potential and yield.

Read More