Expertise documents

expertise_documents

Co-inoculation of selected wine bacteria

The advantages of co-inoculation are numerous, such as ensuring a faster more secure process and reducing time for the MLF. Co-inoculation is an important modulator in sensory development, and it helps limit the development of spoilage microorganisms and thus limits off flavor compound productions.

WE4 US2

 

Wine Expert #8 – the many roles of Nitrogen during alcoholic fermentation

Wine yeast requires certain essential elements to transform must into wine: sugars, vitamins and minerals, some oxygen, and also very importantly, a sufficient concentration of Yeast Asssimilable Nitrogen. This type of nitrogen (YAN) is composed of amino acids, some small peptides and ammonium that can be used by yeast cells to not only complete fermentation, but also to fully develop the sensory profile of the wine. Many wine musts are deficient in nitrogen and the type of nutrient used and the timing of additi on is crucial in the development of AF. WE#8 ENG

Wine Expert #7 – 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. Its 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 Sensywhich 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 Sensywith its low capacity to produce H2S, as well as SO2 and acetaldehyde, will let the varietal aromas be fully expressed. WE #7 - Sigrid