DON Cripples Wheat Industry in Southeast U.S.

Fusarium head blight (FHB, scab) was of little concern last year in the Northern Plains, which produced one of its best wheat and barley crops ever.  It was a different story east of the Mississippi River, however, where large amounts of rainfall made conditions ripe for FHB, which wreaked havoc on wheat yields and resulted in high levels of deoxynivalenol (DON) or vomitoxin. 

Industry experts says FHB damage to farmers and millers in the mid-Atlantic soft red wheat producing region (North Carolina, Georgia, Virginia, extending to Kentucky and Tennessee) in 2003 was unprecedented, crippling grain flow patterns and sales.

Mike Pate, director of technical services at Midstate Mills, Inc., presented a summary of the problem at the National Fusarium Head Blight Forum, held recently in Bloomington, MN.

Midstate Mills is a North Carolina company, family-owned and operated since 1935. The company’s business includes wheat and corn flour milling, baking mix blending, and animal feed production. The company serves a number of different markets with their products including commercial bakeries, foodservice distributors, national fast food and retail accounts, and the wholesale and chain grocery trade. In a single hour, Midstate mills and blends enough flour to make over 790,000 biscuits, or 82,000 pound cakes, or 18.5 million crackers.

Pate, chair of the North American Millers’ Association’s technical committee, says that because of high DON in the 2003 soft red winter wheat crop in mid-Atlantic state, all major mills stopped sourcing wheat from that region on Nov. 1, 2003. 

Midstate and other mills operate on fixed contracts with cake, pastry, cookie and doughnut makers, who pay for a specific amount of flour.  If the supply of quality wheat is insufficient, mills must source wheat to produce enough flour to hold up their end of the contract.

“This might not seem like a significant issue to you…but let’s say I’m selling half a million pounds of flour to a Keebler facility in North Carolina, and all my contracts are based on pulling wheat by truck within a 200-mile radius. Suddenly, your supply source is gone, and you have to ship wheat as far away as 1,200 miles from Ontario by rail.  Guess who’s losing money? And the reason is DON.”

Growers and mills in the region are also affected by the lost confidence of buyers.  “You’re dealing with the perception of customers that our products are not safe,” says Pate.  “When I pick up the phone and call corporations like Sara Lee and they tell me not to ship anymore cake flour because they’re worried about DON limits, I’m in trouble.  These are major players in the food industry.”

In the past, it was thought that DON in wheat could be reduced to acceptable levels by the milling process, a concept called “milling loss,” typically on the order of 50%. Thus, if raw kernels of wheat contained DON of two parts per million, the derivative flour of this wheat would typically test at 1 ppm or less in flour intended for human consumption.

In 2003, however, DON levels of wheat from FHB-infected wheat in mid-Atlantic states weren’t falling as much as expected during milling. For example, raw wheat that may have tested for 2 ppm DON would mill flour testing at 1.8 ppm DON.  This would be too high to meet the federal advisory level of 1 ppm or less in flour intended for human consumption.

“We were wondering what happened.  Has the disease mutated? Are the varieties different?”  Pate says an investigation by various milling entities revealed that there probably never was a significant “milling loss” from separating the pericarp or hard outer covering from the rest of the kernel. 

“The apparent loss can be attributed to the removal by milling precleaning equipment of small shrunken kernels that had high DON levels,” says Pate.  Particularly troublesome with last year’s harvest, however, is that plump kernels infected with DON aren’t getting removed by the cleaning process, and thus entered the milling stream. And millers aren’t going to take chances with flour that may exceed the federal DON advisory level.

Pate points out that North Carolina is one of the nation’s leading producers of pork and poultry. The pork industry alone traditionally accounts for about 40% of North Carolina’s wheat use. However, even the livestock industry is careful about using feed tainted with DON.

“It’s a matter of food safety,” says Pate. “If you cannot provide a safe food commodity to the end user, two things happen to you: you’re not going to have any business, and lawyers are going to step in. Litigation is the watch word for what we do, don’t ever forget that.”

Pate notes that the federal guideline for DON in wheat is now just that; a guideline or advisory. But with further problems, a DON limit could become a statutory law “with a stroke of the pen,” just like the government doesn’t allow blending to lower aflatoxin levels in corn.  “That would mean if I have (flour) over 1 ppm DON, the government could have it destroyed.”

He told crop scientists at the National Fusarium Head Blight Forum that the urgency of solving the problem can’t be stressed enough.

“Don’t think that just because you’ve come up with a better yield or test weight that you’ve accomplished your job,” Pate says matter-of-factly. “It doesn’t stop there.  It has to be acceptable for the baking industry and to the end user.  My charge to you would be to get us a solution, and get it soon, because the future of our industry in the mid-Atlantic states is depending on it.”

The U.S. Wheat and Barley Scab Initiative, which got underway in 1997, is a national research initiative to find multiple solutions for controlling FHB and DON in wheat and barley. Research funded by the Intiative involves crop scientists across the country, including the Dakotas, Minnesota, and Montana.

At the research forum, scientists reported research results and advancements in variety development and uniform screening nurseries; epidemiology (how scab develops, spreads) and disease management; food safety, toxicology, and utilization; biotechnology; chemical and biological control; and germplasm introduction and evaluation.

A full report of research conducted under the U.S. Wheat and Barley Scab Initiative and discussed at the Forum can be found online at www.scabusa.org, under the 2003 National Fusarium Head Blight Forum Proceedings.

Other Challenges: Atkins, Extended Shelf Life

Pate says other issues are facing the flour milling industry as well. Pate says that one challenge which has been good for consumers – but not for flour millers – is the extended shelf life (what the trade calls “ESL”) of bread loaves today. 

Years ago, a loaf of bread would expire in less than five days.  Today, technology and formulation advancements have resulted in a loaf that will stay fresh for over two weeks. “Guess what (the baker) doesn’t need? As much flour. Our flour sales for people who produce white loaf bread have dropped 15-20% because of ESL,” he says.

The Atkins diet is another issue of broad concern for the grain processing industry.  Pate even admits to losing over 50 pounds on the plan.  Nevertheless, he says the milling and baking industry needs to promote the fact that a certain amount of carbohydrate foods need to be included in a long-term sensible diet.