Expertise documents

ESL 2009: Sensory of cool-climate varietals

Proceedings of the XXIst Entretiens Scientifiques Lallemand held in Geisenheim Institute in Germany focused on cool-climate varietals and to understand how wine fermentation impacts their sensory properties.  The meeting also celebrates the 115th anniversary of the Geisenheim Research Centre with a presentation by Prof Manfred Grossmann. Topics presented included Margaret River cool-climate Chardonnay, yeast and its role terroir expression in Germany and France, and how MLF impacts cool-climate varietals. CahierGeisenheimComplet

ESL 2007: Global warming brings new oenological challenges

Proceedings of the XIXth Entretiens Scientifiques Lallemand held in Margaux, France discusses how climate change is impacting grape and wine production.  Topics presented included climate change and viticulture, challenges faced by yeast with higher alcohol, malolactic fermentation and grape phenolic maturity. Cahier19 Lall

ESL 2004: Wine quality and malolactic fermentation

Proceedings of the XVIth Entretiens Scientifiques Lallemand held in Porto, Portugal discusses the role lactic acid bacteria and malolactic fermentation in winemaking.  Topics presented included yeast-bacteria interactions, impact of S-containing amino acids and glutathione on LAB and MLF, producing buttery wines and the LAB genome project. Cahier Lall 5

The New Winemaking Update – Organic Version: Copper sulfate use in organic vineyards – are wine yeast and bacteria affected by this fungicide?

In 2017, the organic vineyard areas had tripled in 10 years and approximately 5% of worldwide vineyards are now under organic certifications.  For organic growers, who cannot use other fungicide sprays, copper sulfate is still an effective tool against downy mildew. With the increased production of organic vineyards in the world, the use of this fungicide has also grown with the expansion of this type of farming. It is known that elevated concentrations of this metal can be toxic to yeasts and bacteria. Our results have shown that wine yeast and bacteria do not appear to be significantly affected by Cu concentrations higher than 15 mg/L, except in the case of malolactic fermentation in white wines, where concentration > 7.5 mg/L can impact the MLF. High pH and high Cu concentrations can impact wine yeast viability and lag phase. To read more about this topic, please consult our Winemaking Update - Organic Version WUP Organic 2020 Cu- ENG LR

Biocontrol agents against Brettanomyces

The contaminating yeast Brettanomyces is a problem, notably for red wines. This yeast is very opportunistic and can survive and multiply in difficult conditions throughout the life of the wine. Hygienic conditions and microbiological controls can inhibit its growth, but will not eliminate it. The goal then is to limit its development, which will in turn limit the production of volatile phenols. The use of SO2 is the preferred method to control its development, however there is a recent trend to reduce the use of SO2 in wine, as well as a general increase in wine pH, which reduces its efficacy. Moreover, there is a great variability in the resistance of SO2 among different Brettanomyces yeasts. The inoculation with our selected natural bacteria is a good option to protect the wine during the fermentation process, and new studies also show their potential to protect wine during the ageing steps against Brettanomyces re-contamination UI #4 Biocontrol MLB ENG