Mid-South producers are building more and more bins for on-farm grain storage. While the practice allows much greater opportunity to take advantage of higher market prices and harvesting flexibility, it does come with some risk.

In Arkansas, currently, some 80 percent of rice is dried commercially.

“Concerns with mycotoxins and kernel discoloration aren’t really too great because the rice is usually dried fairly quickly,” says Terry Siebenmorgen, University of Arkansas food science professor. “The concern there is if it’s dried too quickly it might lead to some milling reductions and possible stain. But most driers do a very good job avoiding those problems.

“The potential worry now is with the increase in the use of on-farm drying systems in which grain is dried over extended periods of time. Sometimes grain with high moisture content just has to be harvested and brought in. So, how best to deal with those circumstances?”

The proper use of those systems -- commonly called “in-bin drying systems with equilibrium moisture content (EMC) controllers” -- is the focus of Griffiths Atungulu’s research.

“With these in bin systems, weather conditions often are a major factor in how quickly grain dries,” says Atungulu, University of Arkansas food science assistant professor. “When you have bins 40 feet high and grain being dried very slowly, it can mean the top layers of grain stay at high moisture content for long periods of time.

“You should assume that the grain entered the bin with some mold that can cause mycotoxin. If the grain is not dried quickly, the relatively high moisture content of grain provides a safe haven for that mold to multiply. Because of that, there’s high potential for mycotoxin production.”