Expertise documents

Proceedings of the XXth Entretiens Scientifiques Lallemand held in Horsens, Denmark discusses how Sulphur compounds impact wine aromas – positively and negatively.  Topics presented included prevalence of wine faults from a blind tasting perspective (International Wine Challenge held annually in London), genetics of Sulphur-containing compounds in Saccharomyces and production by O. oeni during MLF. Cahier20 Lall

Wine yeasts are able to produce volatile aroma compounds from precursors found in the grape musts. Despite this ability, the wine yeast needs an adapted nutrition management (type of nutrient and timing of addition) that will maximize this secondary metabolism. Work done in collaboration with INRA (Montpellier, France) has shown that the type of nutrient, and the timing of addition during alcoholic fermentation has an important impact on the production of fermentative aroma compounds. Stimula Chardonnay™ has been shown to maximize specific aroma compounds in Chardonnay wines UI Stimula Chardonnay 2019 - ENG  

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 addition is crucial in the development of AF. It has been shown that organic nutrients, which N-containing amino acids, peptides and proteins issued from auto-lysed yeast cells found in Fermaid O™ for example, and added at the beginning of fermentation and at 1/3 through the AF, are the best strategy for achieving complete and regular AF and maximizing the sensory potential of the wine. For full article click here WE#8 Nitrogen

The purpose of this booklet is to provide oenologists and winemakers with an outline of the current scientific understanding of yeast nutrition and protection for reliable alcoholic fermentation management. Download PDF