As with all beers, an important part of the brewing process involves the use of malting barley, a cereal grain. Malting barley is a specific type of barley that differs from the feed barley commonly grown. Typically, malting barley lines produce higher levels of amylase enzymes, which convert starch to sugars during the brewing process. These sugars, in turn, are coupled with yeast and converted into alcohol.
Malting barley has other characteristics that are important to the brewer. Plump, uniform kernels are important for producing a good, evenly germinating malt to maximize the malt extract potential. Flavor characteristics of different malting barley varieties is a new area of interest by some brewers — different malting barley varieties can produce different flavors when malted, thus increasing the importance of variety selection in the brewing and malting industry.
Malting barley varieties are available in either two- or six-row head types — based on the arrangements of the kernels. Two-row head types are preferred by most craft brewers, Roth noted. The crop is classified further as either spring or winter, depending on planting season.
Most malting barley is grown in the western United States, Canada and Europe, as many of those climates provide drier growing seasons. But that doesn't mean Pennsylvania can't play a role in the industry.
"Actually, Pennsylvania has a history of growing barley that dates back to William Penn," Roth said. "But, several factors, including Prohibition, caused the malting industry to virtually disappear. It's good to see the industry coming back to life."
With a multitude of winter and spring malting barley varieties available, the first undertaking was to identify which ones would grow well in Pennsylvania and meet grain-quality and yield specifications of the industry. To do that, Roth began collaborations with researchers at malting-barley breeding programs at North Dakota State University and the University of Minnesota, who, in turn, provided seeds from 20 to 30 different varieties from the Midwest and Europe.
Over several planting seasons, Roth and Collins analyzed crop growth, soil conditions, insect damage and yield. They especially focused on disease control, as that is a major challenge associated with growing malting barley.
"Unfortunately, our state's climate is very favorable to the development of fungal diseases, which is a problem for quality and yield in most crops," said Collins. "One fungal disease, fusarium head blight, also called head scab, can result in the production of a toxin, called 'vomitoxin.' In order to prevent this vomitoxin from entering our food supply, we must prevent the disease. So barley disease management is a critical part of growing a crop suitable for malting in our area."
To the researchers' surprise, most European varieties outperformed those from the United States, demonstrating good disease resistance, high yields and good quality. Some of the western lines couldn't withstand the high amount of rain in the region — the moisture caused seeds to germinate in the field, and once that happens, the crop is deemed unacceptable, Roth noted.
To further refine their selections, Roth and Collins sought input from malt house owners as well as Aaron MacLeod, director of Hartwick College Center for Craft Food and Beverage in Oneonta, New York, who analyzed samples for quality and malting characteristics. They are beginning a new collaboration with faculty and students from the new brewing and fermentation program at Pennsylvania College of Technology in Williamsport, a special mission affiliate of Penn State.
In the end, the researchers identified five varieties as standouts. To share this information with growers, they created a factsheet with comprehensive study information — including varieties, seeding, crop rotations, weed and insect control and disease management — which can be viewed by visiting Penn State Extension's website.
Roth and Collins are pleased with how the trials turned out and plan to continue to investigate new malting barley lines in partnership with all of their collaborators.
"What's really exciting is that some of the malting barley varieties we've recommended are showing up in craft beers in Pennsylvania," Roth said. "Another great thing is that the barley that isn't used for brewing still has value as livestock feed. So nothing is wasted."
Collins agreed, adding, "If we as a community feel strongly about local agriculture, and supporting local farming is important to us, then it is critical that we have research conducted locally. The research and education we're doing will make sure that our farmers can be successful and profitable, while keeping toxins out of beer."
This work has been funded, in part, by the United States Wheat and Barley Scab Initiative, a group of federal, state and private-sector scientists working with growers, input providers, millers and food processors from across the country. The initiative is funded through the U.S. Department of Agriculture's Agricultural Research Service.