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

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

YSEO process: a unique yeast production process

Lallemand has developed a unique yeast production process called YSEO® (Yeast Security and Sensory Optimization). This process increases fermentation reliability and security and ensures fewer organoleptic deviations, but not all yeast can be prepared by this process. The process (when compared to non YSEO®):
  • Improves the yeast cells assimilation of essential micronutrients and vitamins.
  • Improves the yeasts ability to implant in the must for a more reliable fermentation.
  • Linked to a reduction in yeast stress thereby reducing H2S, VA and SO2 production.
  • Shorter lag phase.
  • Improves the resistance and adaption of the yeast under difficult fermentation conditions.
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Balanced nutrition for a healthy alcoholic fermentation

Nitrogen is an essential nutrient for smooth alcoholic fermentation (AF). Numerous  studies have shown that nitrogen has a positive impact on the growth and fermentation activity of yeast (Bell et al. 1979, Ough and Lee 1981, Bezenger and Navarro 1987). Deficiencies in yeast-available nitrogen (YAN) in the must significantly increase the risk of sluggish or stuck fermentations because they can arrest protein synthesis in the yeast cells. We consider a must with an initial sugar level of about 200 g/L to be deficient when its YAN concentration is about 150 mg/L (Henschke and Jiranek 1993). A YAN deficiency in the must can also cause the yeast to increase the production of H2S (Henschke and Jiranek, 1991). This edition of the Winemaking update focuses on the impact of balanced nutrition on alcoholic fermentation.

Lallemand Winemaking Update #13 2010 - Balanced nutirtion