Improved control of wine microbiology in cool climate grape wine production

2007 Impact statement
  • Mira de Orduna Heidinger, Ramon

abstract

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.

submitted by

issue being addressed

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.

response

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 sulphur dioxide. By reducing acetaldehyde and, consequently, sulphur dioxide levels, we are able to reduce the incidence of headaches caused in sensitive consumers, as well.

impact assessment

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

academic priority area

topic description

Wine Microbiology

has geographic focus

funding source description

  • Ontario Centres of Excellence - Materials and Manufacturing Ontario
  • Industry Funds
  • National Science and Engineering Research Council, Canada
  • Ontario Ministry of Agriculture and Food

collaborators

University of Guelph

key personnel

Ramón Mira de Orduña

mission focus

From CALS annual faculty reporting. Imported on August 5, 2008