Barley’s newly discovered novel flavors could be revolutionary for beer world

29 Nov 2017 --- Barley may now be ready for its time in the brewing spotlight, according to studies in the peer-reviewed Journal of the American Society of Brewing Chemists. A research team led by the US’ Oregon State University, also involving researchers at The Sainsbury Laboratory, Norwich, UK, found notable differences in the taste of beers malted from barley varieties said to have flavor qualities.

The research project set out to test the theory that barley cultivar and the place it is grown can affect beer flavor. Until now it was an opinion widely held in the brewing trade that it was the malting process, not the barley that contributed to the flavor and aroma of beer, according to Norwich’s John Innes Centre. Additional flavor enhancements were provided by the choice of hops, water and yeast; sometimes, they came from fruit, coffee and spices.

Varieties of barley were mainly selected for their suitability for the malting process and the efficiency with which barley is turned into sugary malt. However, many brewers insisted that certain barley varieties did contribute to flavor above and beyond the malting process. In addition to genetics, they believed, environment and location – what the wine industry calls terroir – also played a part.

These brewers were correct, according to Dr. Matthew Moscou, one of the authors of the study from The Sainsbury Laboratory. “The malting process directly impacts the wider profiles of flavor – how you get a pale ale, a lager or a porter – but what this study shows is that subtle flavor profile of the barley variety selected carries through that process,” Moscou says.

“This provides the motivation to look into our seed base and start looking at those cultivars that were grown in the past and asking what kind of flavor profiles we can bring into modern breeding,” Dr. Moscou adds.

The findings don’t mean consumers are going to see a barley-flavored brew anytime soon in their local pub or supermarket, but the findings are an important first step toward a potential new market for beer connoisseurs, according to OSU barley breeder Pat Hayes.

“We started this project with a question: Are there are novel flavors in barley that carry through malting and brewing and into beer? This is a revolutionary idea in the brewing world. We found that the answer is yes,” Hayes says. “These positive beer flavor attributes provide new opportunities for brewers and expanded horizons for consumers.”

Barley crossbreeding leads to varied progeny
Barley World, Hayes's research group at OSU, with financial support from the beer industry, began with two barley varieties reputed to have positive flavor attributes in beer: Golden Promise, developed and released in the UK, and OSU's own barley variety, Full Pint. They then crossbred the two varieties.

That cross-breeding resulted in several hundred breeding lines of genetic seed stock, Hayes says. This allowed researchers to observe useful field traits.

There was a logistical challenge in preparing that barley for brewing and sensory testing, according to Hayes. OSU's progeny of Golden Promise and Full Pint each yielded only about 200g of malt – not enough for a reasonable sample to produce large quantities of beer for a standard sensory panel.

At this point, OSU teamed with Rahr Malting Co. in Minnesota and New Glarus Brewing in Wisconsin. The companies had developed a “nano” brewing system that could produce a single bottle of beer from each unique malt. Dustin Herb, a graduate student in OSU's College of Agricultural Sciences, spent almost a year at Rahr Malting participating in the micro-malting, nano-brewing and sensory processes.

Out of that initial partnership, about 150 beers were prepared for sensory testing. Each expert panelist tasted each of the beers once and then rated it on a scale in its amount of difference compared to an industry standard control beer.

The ratings were based on a flavor wheel of ten descriptors. The descriptors were: cereal, color, floral, fruit, grass, honey, malt, sweet, toasted and toffee.

The panelists found that beer brewed with Golden Promise scored significantly higher in fruit, floral and grass flavors. Beer with Full Pint was significantly higher in malt, toffee and toasted flavors.

“The progeny is showing all possible combinations of those traits,” Hayes says. “And, since we had been doing DNA fingerprinting on these progenies, we can assign certain regions of the barley genome as being responsible for these flavors. We also found that there were some differences based on where the barley was grown, but the genetic effect was larger than the environment.”

“Major targets in barley breeding are yield and malting quality,” says Dr. Moscou. “But this study has shown that the flavor profile has little to do with the malting characteristics. That’s important because it says you can breed barley for malting ... but you won’t necessarily be breeding for flavor.”

Based on the results of more cross-breeding between Golden Promise and Full Pint, finer structure genetic mapping of barley flavor genes is underway with Rahr Malting Co. The researchers are also working with Deschutes Brewery in Bend, Oregon to brew more representative beers from three of the selected progeny.

The study findings conclude: “Barley varieties make different contributions to beer flavor, growing environment can have an effect, variety flavor contributions have a genetic basis and variety contributions to beer flavor develop during malting.”