H2S production by wine yeast during alcoholic fermentation
Hydrogen sulphide (rotten egg) aroma is a serious fault in wine and will result in quality loss in the final product. it's production is mainly found during alcoholic fermentation. H2S production by wine yeast varies based on the yeast used as well as on the environmental factors, especially the assimilable nitrogen concentration and micronutriens present. Ranging from low to high producers, this characteristic is important to take into account, as well as the nutritional status of the must, when deciding on a fermentation strategy.
The best way to avoid formation of H2S during winemaking are to choose a low H2S yeast producer and apply good fermentation practices, and also use wine yeast such as Lalvin Sensy™ which have been especially selected to avoid the production of this compound while keeping in mind a good nutrition and oxygen addition strategy. It is adapted to white winemaking fermentation where the conditions (such as low NTU, low temperature, low YAN) could affect H2S formation, and the Lalvin Sensy™ with its low capacity to produce H2S, as well as SO2 and acetaldehyde, will let the varietal aromas be fully expressed.