The Daily Beast has misunderstood, unfortunately, and the rose-scented CRISPR beer does not exist yet. But researchers are hopeful to try it in pilot-scale in the near future. A team from the University of Leuven in Belgium has identified two genes that could be used to generate novel flavor profiles in alcoholic beverages. They are called TOR1 and FAS2 and work by increasing the production of phenylethyl acetate in yeast (Saccharomyces cerevisiae). CRISPR helped to swap the scented alleles into standard strains, which suddenly began producing more floral aromas.
The experiment, described in the American Society for Microbiology journal mBio, is a taste of what to expect from gene editing for improving industrial yeasts. By overcoming the limitations of traditional breeding techniques, which are slow, expensive and inaccurate, CRISPR is going to extend the palette of aromas available to brewers and winemakers. The Leuven team will now partner with a brewery to test their experimental yeast with several batches of beer.
New strains can move quickly from the lab bench to the market. “After lab scale fermentations (0.5-5 liters), pilot fermentations (100-1000 l) and commercial fermentations (50,000-500,000 l or more) have to be carried out. If things go well and the beer is good each time, this could be done within a year”, the study author Johan Thevelein told us. Regulatory approval can add another 1-2 years, but the main problem here is public acceptance. CRISPR strains developed this way are not transgenic but cisgenic, i.e., modified only with natural alleles of the same species. “According to European regulations they are GM strains, but they are indistinguishable from natural strains or spontaneous or induced mutants. The impossibility to prove that they are GMOs creates a dilemma for regulators, which the European Commission has not been able to solve yet,” Thevelein explains.
Is the beer market more biotech-friendly than wine? “I’m afraid the attitude is the same. A major difference is that 80% of the flavor of a beer is determined by the yeast and the rest by other ingredients, while in wine about 80% is determined by the grape and the rest by the yeast and other ingredients.” Only time will tell how warmly consumers will welcome CRISPR foods; in the meantime, the technique is speeding up the study of the yeast genome. This knowledge will help researchers to genetically improve their strains using conventional techniques. “We can develop non-CRISPR strains by marker-assisted breeding, looking for specific mutations to predict the presence of high rose flavor production.”