Yeasts are single-celled fungi responsible for converting sugar to alcohol through fermentation in foods like chocolate, cheese, bread, and drinks like beer and wine; in nature yeasts are found on the leaves of different plants so it is no surprise that they could also be found on arthropods, including bees, wasps, and beetles.
Yeast contributes to the flavor of beer, and in commercial and craft beers there are two species typically used. New yeasts could mean new flavors and that’s exactly what NC State scientists in the Food Sciences and Bioprocessing labs are hoping for.
Alex Smith, the head brewer at Raleigh Brewing Company says there is definitely a market for new kinds of yeasts, and a North Carolina start-up called SouthYeast is already harvesting wild yeasts from nature. In a market that is competitive, you must do something to standout, and with 132 members in the N.C. Craft Brewers Guild, the market is as competitive as ever.
Initially, to find new yeasts, NCSU researchers turned to wasps as they have been known to carry yeasts on their bodies and house them during the winter. Although it took a few months, Anne Madden who is a researcher at NCSU, along with her colleagues, successfully cultivated a number of different yeast species from wasp bodies.
According to Madden, not all species have the correct metabolism required to make beer and some die when the alcohol level of their environment rises to 1 or 2 percent. Through a series of biochemical and genetic tests, the team narrowed down which species to work with but their choice also was the result of guesswork, according to Madden.
Since yeast effects the taste of beer, even if it could produce beer, it may not produce great tasting beer; as you can imagine, wild yeasts often produce funky flavors so it’s not just about finding wild yeast but the right wild yeast!
The scientists were surprised that the very first batch of beer made from these wild yeasts was drinkable, though very sour and was considered an “extra special bitter.” By experimenting with other recipes for ambers and blondes, these same yeasts produced honey, apple, floral, and subtle sour notes. But Madden said the most exciting part is that it’s oftentimes the same chemical produced by those fruits being produced by the yeasts and our bodies recognize it as such. This means we could get actual natural flavors instead of adding flavors to beer and that is going to be a game changer.
The NCSU team debuted its wasp-derived beer at the World Beer Festival in Raleigh last year, and then poured their follow-up, a beer brewed from bumblebee yeast and named “Bumblebeer,” at the 2014 Wake County Brewers Expo.
