Powering Research for Safer Barley Malting
Agricultural Research Service (ARS) researchers partnered with Bradley University to combine biological research with applied engineering to develop innovative barley micro malting devices that use natural compounds to prevent microbial [fungal] contamination during the malting process. This addresses a problem that costs the U.S. malting and distilling industry millions of dollars each year.
The fungus Fusarium graminearum can infect cereal crops during flowering and contaminate grains such as barley, wheat, oats, and rye with mycotoxins. Mycotoxins are compounds produced by fungi that can pose serious health risks to people and livestock.
Even low levels of fungal contamination in malting barley can cause big problems because toxins can continue to accumulate during the malting process. Although there are strict industry standards in place to ensure public health, safe and cost-effective technologies are needed to prevent product quality issues and significant financial losses suffered by the malting and brewing industries due to this problem.
before (left) and after (right) kilning. (Mastanjevic et al, 2019)
In studies led by ARS Plant Physiologist William Hay, a team of researchers at the National Center for Agricultural Utilization Research (NCAUR) in Peoria, IL, found natural gaseous compounds produced by mustard plants that can limit fungal growth and prevent contamination with toxins during malting, thereby enhancing food safety. The beneficial aspect of this discovery is that the compound is already approved and used in the food industry as a flavoring and food additive.
ARS researchers proceeded to develop a laboratory method that uses these compounds as natural “biofumigants.” The method effectively solves the microbial contaminant problem without damaging the barley seeds or leaving harmful residue post-processing. It also enhances the quality of the malt.
However, another challenge remained, “How can ARS help the malting and brewing industry apply this treatment in their production facilities?”
Hay received a USDA Innovation Grant and is collaborating with Ahmad Fakheri, a mechanical engineering professor at Bradley University, on a multi-year capstone project. Guided by Fakheri, Hay, and ARS researcher Jason Walling from the ARS Cereal Crop Research Unit in Madison, WI, senior mechanical engineering students were tasked with the design and development of a self-contained micro-malting device capable of performing the three primary stages of malting, steeping, germination, and kilning, for cereal grains such as barley. The systemwas also required to incorporate controlled treatment with natural biofumigants to mitigate microbial growth while preserving grain viability and malt quality.
model (right). (Images provided by William Hay and Martha Vaughan)
“The Micro Malting Machine has the potential to be scaled for use in large breweries,” explained Hay. “Our goal was to create devices for food safety research that can study pathogens, enhance food safety, and evaluate treatments to identify new compounds that meet industry standards.”
“It’s important to make the devices scalable so that, once we demonstrate their effectiveness, they could be incorporated into large-scale malting systems within the industry,” added Hay. “The engineering students’ innovation and applied knowledge in these devices have been instrumental in helping ARS develop a prototype that could eventually be adopted by the industry.”
ARS researchers are collaborating with the American Malting Barley Association and the Distiller's Technology Council to ensure this technology is accessible to both micro-breweries and large-scale operations with the objective of protecting grains from fungal contamination, enhancing food safety, and supporting farmers and producers of U.S. agricultural commodities.
“The presence of microbes on grain can pose processing challenges and affect flavor profiles,” said Scott Heisel of the American Malting Barley Association. “Although malting barley is selected to minimize fungal contamination, it is not feasible to eliminate all microbes from the barley supply chain. We are excited to see a fumigation method using natural compounds to inhibit fungal growth during processing. It represents a viable strategy for preserving barley quality and delivering added value to both producers and consumers.”
Details about the study were published in ACS Agricultural Science & Technology.
Article by the American Malting Barley Association: Designing a barley micro malting system for food safety research. By Maribel Alonso, ARS’s Office of Communications