Montanans turn barley into high-value feed, ethanol

By Susanne Retka Schill | July 23, 2014

Researchers in Montana are looking at an enzymatic treatment for barley that produces a high-value protein concentrate, describing ethanol as the process coproduct.  

Feed barley has been an important crop in Montana that has declined in recent years, although it is an important rotation crop for winter wheat in the state, explained Cliff Bradley, cofounder of Montana Microbial Products LLC. “New high value markets would help small grain production,” Bradley said.

Montana Microbial and the USDA Agricultural Research Service are co-inventors of an enzymatic process that concentrates the protein in barley. The enzymes also alleviate the viscosity issue with barley mash in the ethanol process. “We hydrolyze the beta glucans which cause much of the viscosity,” Bradley said.

The enzymes facilitate removing the protein at the front end of the process, producing a feed concentrate which contains 54 to 58 percent protein and less than 5 percent fiber. The carbohydrates are then sent through the rest of the traditional ethanol process. There are a few other significant differences, Bradley explained. “There are no DDGS. We need a finer grind than most [ethanol plants] do, and the process flow is different.” The ethanol yield from the enzymatically treated barley is similar to yield from barley in a conventional ethanol production process, he said, adding that while barley is more variable than corn, the rule of thumb is 2.2 gallons of ethanol per 48-pound-bushel of barley.

The economics are quite different as well. “The big economic thing is producing a high protein concentrate that competes against soymeal and fishmeal. We’re talking feed that sells at $1,000 per ton instead of around $200 a ton.”  The enzymatic process will work with other grains, Bradley added. “The patent names every grain we could think of,” most of which were tested in lab trials.  The researchers chose to focus on barley partly because of its low cost and relatively high levels of protein, along with the need for an alternative market for Montana barley growers. Bradley said a preliminary business plan for a small scale plant calculated that 800,000 to 1 million bushels of barley would produce 5,000 ton of barley protein concentrate annually plus 2 million gallons of ethanol. Montana feed barley has sold in the range of $7 to $10 per hundredweight in recent years, he added.

The new high-protein product produced by this technology should help fill the gap for more plant-based protein sources as alternatives to fishmeal, according to fish physiologist Rick Barrows. The researcher is based in Bozeman, Montana, and works with the ARS Small Grains and Potato Germplasm Research Unit in Aberdeen, Idaho. In addition, barley protein concentrate has less variability in composition and is less expensive than most fishmeals. “The process is designed to protect the protein and make ethanol, so we do not have the problems associated with DDGS for fish feeds,” Barrow said.  “Barley protein concentrate has been shown to be effective for fish feeds and has applications in the pet food industry as well. Also, since barley that is too high in protein for malting barley is a good material for the process, a new market for this material is developed.”

Barrows’ team has tested barley protein concentrate in rainbow trout and found digestibility—the percentage of nutrients available to the fish—to be as high as 95 percent. A 2013 paper on feed trials with a 53 percent protein barley concentrate reported rations with 11 or 22 percent barley protein compared favorably to the fishmeal base diet and other plant proteins when fed to Atlantic salmon. 

Montana Microbial Products currently bringing a commercial prototype plant online in Montana to produce barley protein concentrate for aquaculture trials. “For a lot of the big aquafeed companies, a sample is 50 tons,” Bradley added. “So we sized our plant accordingly.” He hopes the company will be building a full commercial plant within 18 months to two years.