Location: Food and Feed Safety ResearchTitle: Inhibition of bacterial and filamentous fungal growth in high moisture, nonsterile corn with intermittent pumping of trans-2-hexenal vapor
Submitted to: Journal of Food Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/11/2013
Publication Date: 8/20/2013
Citation: De Lucca II, A.J., Carter Wientjes, C.H., Boue, S.M., Lovisa, M.P., Bhatnagar, D. 2013. Inhibition of bacterial and filamentous fungal growth in high moisture, nonsterile corn with intermittent pumping of trans-2-hexenal vapor. Journal of Food Science. 78(7):M1029-M1035.
Interpretive Summary: Trans-2-hexenal (T-2-H) is produced by soybeans and other plants and has antimicrobial properties and is easily vaporized. The fungus, Aspergillus flavus, commonly is found on oilseeds such as corn before and after harvesting. If the crop is wet after harvesting, the fungus can grow and produce a toxin, called aflatoxin, which causes liver cancer. This is a serious threat to food and feed supplies throughout the world and results in the loss of millions of dollars of corn, peanut and cottonseed in the United States each year. This study utilized a bench-top model of stored, wet corn to determine whether intermittently pumped (30 min per 2h or 12h) vaporized T-2-H would significantly reduce bacteria and fungi naturally present on corn as well as A. flavus inoculated onto corn. Results showed that vaporized T-2-H significantly reduces bacterial and fungal viability with a few as two pump cycles during the first 24h, Day 3, 5, and 7 after treatment was initiated saw microbial populations drop to nearly zero. The data suggests that this plant-produced compound could be used to protect stored grain from bacterial and fungal growth as well as aflatoxin production.
Technical Abstract: Trans-2-hexenal (T-2-H), a plant-produced aldehyde, was intermittently pumped over a 7 d period into a small, bench top model of stored corn (non-sterile, moisture content about 23%). Naturally occurring bacteria and fungi, including added Aspergillus flavus, grew rapidly on corn not treated with T-2-H vapor. However, intermittently pumped T-2-H (30 min per 2h or 30 min per 12h) significantly reduced bacterial and fungal viable populations, with nearly 100% viability loss observed after only two pumping cycles during the first 24h of incubation. Data suggest that intermittent fumigation of stored corn with T-2-H could prevent growth of bacteria and mycotoxigenic fungi such as A. flavus.