Controlling Fusarium contamination of malting barley with Brassicaceae seed meal volatiles

Authors: Hay, William; VAUGHN, STEVEN - Retired ARS Employee; McCormick, Susan; BERHOW, MARK - Retired ARS Employee; Busman, Mark; Brownstein, Korey; Vaughan, Martha

Submitted to: ACS Agricultural Science and Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/10/2025
Publication Date: 2/17/2025
Citation: Hay, W.T., Vaughn, S.F., McCormick, S.P., Berhow, M.A., Busman, M., Brownstein, K.J., Vaughan, M.M. 2025. Controlling Fusarium contamination of malting barley with Brassicaceae seed meal volatiles. ACS Agricultural Science & Technology. https://doi.org/10.1021/acsagscitech.4c00458?urlappend=%3Fref%3DPDF&jav=VoR&rel=cite-as.
DOI: https://doi.org/10.1021/acsagscitech.4c00458?urlappend=%3Fref%3DPDF&jav=VoR&rel=cite-as

Interpretive Summary: Malting of barley is an essential step in the production of beer. But the moisture and temperature conditions used in the barley malting procedure can promote undesirable growth of fungi. Toxin-producing fungi, such as Fusarium graminearum, can cause millions of dollars in annual losses for barley malters. ARS researchers in Peoria, Illinois, developed a technology to protect barley from harmful fungi using compounds from the mustard family. Seeds from the mustard family have volatile natural chemicals, called isothiocyanates, that protect the plant. Ground seed meal from some varieties of mustard were used as a source of volatile compounds to treat fungi infected malting barley. The volatile compounds slowed fungal growth and stopped fungal toxin contamination. The treatment did not harm the barley. After the malting was complete, no mustard volatile compounds were found on the malted grain. This technology is a new natural method for protecting the food safety of malted grains and should provide an economic benefit to the multi-billion dollar malting industry.

Technical Abstract: Mycotoxin accumulation during the malting of wheat and barley grain causes millions of dollars in annual losses for the U.S. malting and brewing industry. This research investigates the use of biofumigant treatments from plant derived metabolites to reduce grain Fusarium contamination and mycotoxin production during malting. Defatted seed meals from five glucosinolate-containing members of the Brassicaceae Family: Brassica juncea, Brassica carinata, Lepidium sativum, Sinapis alba, and Thlaspi arvense were used to fumigate inoculated wheat and barley. Naturally produced gaseous allyl isothiocyanate was able to control Fusarium graminearum growth and mycotoxin contamination without harming wheat or barley germination. Treatment of Fusarium inoculated, and naturally contaminated, barley with volatiles from defatted Brassica juncea, in simulated malting conditions, completely prevented mycotoxin accumulation. No residual isothiocyanates were detected on the malted barley post kilning. This research demonstrates an alternative valorization of Brassicaceae seed meal byproducts as potent inhibitors of fungal contamination during malting.