Improved control of wine microbiology in cool-climate grape wine production


2007 to 2020


Quality wine production depends on maintaining proper microbiological control during the transformation of grape juice into wine and its conservation. Our research provides microbiological techniques that allow winemakers to reduce microbial products, which can cause negative effects—such as headaches—to wine consumers, thus increasing the percentage of consumers able to take advantage of the health benefits related to moderate wine consumption.


Wine production is essentially a microbiological process where yeast and bacteria consume sugars, acids and other compounds leading to the formation of a microbiologically safe and healthy beverage. A poorly managed microbiology in the winery will not allow the wine to express the full grape aroma potential in the best case or lead to spoiled and potentially unmarketable products that may lead to negative effects—such as headache—in sensitive wine consumers.


Our research has identified microorganisms and metabolic transformations that have the potential to decrease final wine quality, leading to loss of product and income. Specifically, we study the degradation of amino acids by lactic acid bacteria, which may lead to the formation of precursors of the food contaminant ethyl carbamate, or biogenic amines, which may be responsible for headaches in sensitive consumers. We also investigate methods to reduce the concentration of a compound called acetaldehyde, which affects the utilization of the wine preservative sulfur dioxide. By reducing acetaldehyde and, consequently, sulfur dioxide levels, we are able to reduce the incidence of headaches caused in sensitive consumers as well.


Within the last eight years, we have published in scientific journals as well as presented at scientific and applied conferences to disseminate our research results. Research-derived recommendations to reduce the formation of citrulline, an ethyl carbamate precursor, from arginine degradation have been included in the ethyl carbamate prevention manual published by C. Butzke and L. Bisson. Together with other strategies, recommendations stemming from our results have been highly effective in reducing ethyl carbamate concentration in wines. Recommendations on acetaldehyde and sulfur dioxide reduction in wines have been provided to the wine industry at international meetings in recent years, as well. Once implemented, wines with lower sulfur dioxide levels will be available for consumers who are sensitive to this preservative.

Submitted by: 

  • Mira de Orduna Heidinger, Ramon

Researchers involved: 

  • Mira de Orduna Heidinger, Ramon

Organizations involved: 

  • University of Guelph

International focus: 

  • United States of America
  • Argentina
  • Australia
  • Canada
  • Chile
  • China
  • France
  • Germany
  • India
  • Italy
  • New Zealand
  • South Africa

United States focus: 

  • New York
  • Delaware

New York State focus: 

  • Cattaraugus
  • Cayuga
  • Chautauqua
  • Delaware
  • Dutchess
  • Erie
  • Niagara
  • Ontario
  • Schuyler
  • Seneca
  • Steuben
  • Suffolk
  • Tompkins
  • Yates