BURLEY — As combines chew through acres of ripe wheat across southern Idaho, growers are more worried about getting the crop harvested than storing it.
But as the acres planted to speciality varieties increase and growers seek to improve profitability by marketing year-round, on-farm storage is becoming more prevalent across southern Idaho. That trend has millers and bakers thinking more about how that wheat is stored.
Wheat is no longer considered a low-risk commodity when it comes to food safety, Reuben McLean, director of quality and regulation for Grain Craft, told grain growers during the University of Idaho cereal school. “Wheat is now considered a medium to high-risk commodity and it’s getting an awful lot of attention.”
Every year in the United States, one out of six Americans gets sick from foodborne disease, resulting in approximately 128,000 hospitalizations and 3,000 deaths, according to the Center for Disease Control in 2011. Most of these illnesses are attributed to salmonella and E. coli O157:H7, microorganisms that are often associated with manure.
While livestock manure is not an issue with wheat kernels, rodents and birds are also sources of E. coli and can contaminate exposed storage piles. General Mills was forced to recall flour-based products in 2016 after 111 people became ill.
“Storage is critical for us as millers,” McLean said.
Storing wheat in bins or silos is the preferred practice to reduce the potential for pests or wildlife to access grain. Tarping ground piles is also acceptable, McLean said. Grain Craft utilizes tarped piles with air flow at its facilities.
Exposed or untarped piles are a red flag for millers. McLean is also concerned about a growing trend of using silage bags to store wheat. It’s become popular in the southeastern U.S. but high humidity has caused spoilage issues. Anytime the bags are punctured by critters chewing on them, yeast or mold can grow by the hole and quickly spread through the bag.
“My experience with these bags has not been good,” McLean said. “They are truly designed to store feed products, not food ingredients.”
In addition to how grain is stored, millers are also concerned about how long grain is stored before it is ground. Millers like to see wheat is stored for 30 to 60 days before it is milled to increase extraction rates and baking quality.
Wheat needs to “sweat” after harvest to let the endosperm harden and the bran separate. Milling wheat fresh out of the field yields primarily bran, which reduces the flour yield per bushel of wheat and increases costs to millers.
Changes in moisture during storage are also associated with increased protein. Higher protein wheat is preferable for products such as bread and pizza dough.
Most flour-based products also undergo a validated kill step at the point of production, such as baking or cooking, which reduces potential risk to consumers. But farmers should still be aware of consumer perceptions when they see exposed grain piles, McLean said.
The USDA Farm Service Agency has loans available to help farmers purchase grain storage bins. Talk to your local FSA office for more information.