GM yeast variety has no effect on wine quality, reveal new trials
production has been found to behave similarly to the parent
commercial yeast strains during fermentation, according to its
manufacturer First Venture Technologies.
The biotech firm yesterday announced that preliminary findings from a number of separate fermentation trials during the 2006 fall harvest were in line with the company's internal testing. First Venture Technologies' propriety yeast claims to be able to reduce levels of the carcinogen ethyl carbamate, a compound that can naturally occur in fermented foods and beverages, such as wine, beer and bread. The firm says its yeast can reduce levels of the substance in red wine by up to 89 percent, and in bread by up to 54 percent. "No significant differences were detected between the urea-degrading strains and their parent strains for the enological parameters that were evaluated," said Dr Linda Bisson of the University of California, Davis, who was among the group of experts evaluating the yeast's performance. "We found no issues with the fermentations or the wines made from these new yeasts to indicate any significant impact under commercial conditions," she added. Also known as urethane, ethyl carbamate, is formed during fermentation, distillation or storage, and can be present in widely consumed foods such as wine, distilled spirits, bread, yogurt and soy products. For example, in wine production, yeast is used in a fermentation process to convert grape juice into wine, explains the company. Arginine, one of the most abundance amino acids in grape juice, is taken up by yeast as a nutrient and metabolized to produce urea. Urea then accumulates in the yeast cell until it reaches a critical concentration, at which point it is released into the wine. Urea spontaneously reacts with the alcohol in the wine to form ethyl carbamate. The chemical reaction between urea and ethanol is exponentially accelerated at elevated temperatures. In October, Environment Canada approved the import and manufacture of First Venture Technologies' yeast variety. The agency's endorsement of the environmental safety of the yeast follows the Generally Regarded As Safe (GRAS) status received from the US Food and Drug Administration (FDA) in January 2006. The company said it hopes the new approval will greatly assist its marketing efforts. First Venture Technologies is currently commercializing its platform yeast technology, which it has exclusively licensed from the University of British Columbia (UBC), and is developing the technology in partnership with UBC's Wine Research Centre. According to Andy Starr, the firm's director of marketing and business development, the primary purpose of the recent trials was to put the yeasts through numerous and varying enological and viticultural scenarios that commercial winemakers deal with everyday. "We are pleased that it appears the yeasts produce wines with similar sensory and fermentation process characteristics. These results demonstrate that winemakers can confidently use the yeasts in full-scale wine production. Knowing that the yeasts have no undesirable effect on wine quality, First Venture can develop usage protocols to provide the 'best practices use' of the yeasts under key commercial criteria," he said. First Venture Technologies claims the use of its yeast variety is currently the most economically-viable solution to reduce or eliminate ethyl carbamate levels in wine and fortified spirits. According to the firm, international monitoring of the component has been going on for 20 years by public health groups such as the FDA, the Liquor Control Board of Ontario and the World Health Organization (WHO). A joint Food and Agriculture Organisation and WHO scientific panel last year concluded that that ethyl carbamate is genotoxic and is a multisite carcinogen in all animal species tested. The chemical is considered to be a potential carcinogen in humans. Europe's Food Safety Authority (EFSA) recently called on regulators to send in any data on levels of ethyl carbamate and cyanides in foods and beverages. In particular EFSA wants information on alcoholic beverages such as stone fruit brandies. EFSA plans to use the data in its assessment of the possible health risks posed by the two classes of chemicals. If high levels are found, the risk assessment could lead to a regulatory pressure on food processors to change their techniques to reduce the chemicals in their products. The same fears about acrylamide and benzene, both by-products of processing or storage, spurred the industry to look at ways to change their processes in a bid to reduce the levels of those chemicals. An international PCT patent application on this urea-degrading yeast technology has been filed. In addition, national jurisdictional patent filings have been made in 22 countries.