Expertise documents

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

The MBR process for wine bacteria – Under Investigation

The high performance MBR process for wine bacteria is a specific production process ensuring optimal conditions for the wine bacteria to develop and carry on malolactic fermentation in wine.  The latest research is summarized in the new Under Investigation UI Bacteria #3-ENG AUS

Wine bacteria to control volatile phenols from Brettanomyces

This issue of the Winemaking Update explores a natural way to control Brettanomyces yeast and the volatile phenols they produce, with selected wine bacteria used to conduct malolactic fermentation.

WUP #2 2014 Australia

 

A new concept of Lactobacillus plantarum wine bacteria in high pH wines

This edition of the Winemaking Update presents the latest findings on the use of Lactobacillus plantarum wine bacteria based on new concepts for achieving MLF and for limiting the growth of indigenousflora and possible harmful wine microbes.

WUP No 1-2015 ML Prime - Australia