CORVALLIS, Ore. — A new study published by researchers at Oregon State University (OSU) found that beers brewed with a new genetically modified yeast have more intense hop flavors.
The yeast increases the presence of certain chemicals that are responsible for the stereotypical flavors one might find in an India Pale Ale, or IPA. The best part is that it does this without brewers needing to add more hops.
According to researchers in Corvallis, this is a big deal, as climate change, droughts and wildfires make it harder to produce hops. With the increase in popularity of IPAs and other fruity and refreshing beers nationwide, the innovation may help with possible supply shortages.
OTHER STORIES: Oregon State researchers find regional differences in hops and resulting beer flavors, aromas
Hop forward beers, like those created with the genetically modified yeast, typically contain compounds called "thiols." These are the chemicals which are responsible for the more fruity and tropical aromas of some brews. However, according to researchers, thiol levels can vary from harvest to harvest and from one variety of hops to another.
With the high price of hops and increased concerns about sustainability, a group of researchers set out to find a way to boost the amount of thiols in beer without adding more hops. The group includes a former OSU graduate, who now works at Boston Beer Company, and a team of scientists at Berkeley-Yeast.
The team was able to successfully change an existing strain of brewers yeast using the science of genetic modification. The researchers cracked the code by getting the yeast to change other chemicals that are present during the brewing process into thiols. This conversion wouldn't happen without the updated yeast, resulting in overall higher levels of thiols in the beers researchers brewed.
The beverages brewed by OSU were described by tasters as intensely fruity and tropical. The beers on average had up to 73 times higher levels of one key thiol researchers measured than a beer brewed with the unmodified "parent" yeast. Scientists said the new yeast didn't create any bad flavors, or affect the fermentation process in any negative way.
It's possible that people have already tasted a beer brewed with the new yeast, as it was made available to brewers early on in its development. OSU estimates the strain is already being used by more than 100 breweries nationwide. It is especially popular with small scale brewers as the price of hops increases.
OSU researchers note that the strain is not intended to be a replacement for hops. Instead they see the new yeast as another weapon in a brewers arsenal to deliver the desired flavor while improving on the sustainability of the industry. Beers brewed with the yeast still have hops, they just require less to achieve the same levels of flavor. The study was published in the scientific journal on Fermentation.
