If falling number and DON (deoxynivalenol) are added as wheat-grading factors will it help or hurt wheat producers?
That sums up the discussion after Doug Chorney, assistant chief commissioner of the Canadian Grain Commission (CGC), spoke at the Keystone Agricultural Producers’ (KAP) advisory council on April 2.
KAP didn’t take a position, but its Grain and Oilseeds committee is preparing one to submit to the CGC before its May 10 consultation deadline.
Why it matters: While objective measurements are potentially more accurate, farmers want to know if the extra cost will be offset by the benefits.
Last month the CGC issued a discussion paper asking for feedback on the idea.
Falling number and DON play a role in what farmers are paid for wheat, but the visual proxies used now — sprout damage for falling number and fusarium-damaged kernels (FDK) for DON — are grading factors. They aren’t as accurate as scientific measurements, but are cheaper and faster.
When wheat germinates it releases an enzyme called alpha-amylase, which breaks down starch so the seed has energy to grow.
“Wheat with sprout damage affects end-use quality — sticky dough that’s hard to handle,” Chorney said.
When buyers see sprouted wheat they know the end-use quality will be affected. But the best way to assess the impact is the falling number test.
After preparing a slurry of flour and water a plunger is dropped through it and timed. The faster the plunger drops the poorer the end-use quality of the flour.
But are falling number tests practical at every elevator? Rapid visco analyzers are machines that measure alpha-amylase and could be an alternative. But a CGC-led experiment in 2006-07 showed they were inaccurate, at least in that setting, and also expensive at about $50,000 each.
One option is for the CGC to make falling number a grading factor with a minimum falling number for each grade, Chorney said.
“That could be an example of the least intrusive approach to this idea,” he said. “So you wouldn’t be expected to test every sample that’s being delivered in that case.”
Then if the farmer didn’t agree with the grain buyer’s assessment he or she could ask the CGC to determine the falling number under its ‘subjective to (CGC) inspector’s grade and dockage’ authority.
“You would only be using the test when you had a challenge or dispute,” Chorney said.
DON is a mycotoxin sometimes produced by the fungal disease fusarium head blight. Often there’s a predictable relationship between fusarium-damaged kernels and DON levels, but not always.
Lateral flow strip technology offers a simple, accurate and cost-effective way to test DON levels perhaps even on the elevator driveway.
The CGC could make DON a grading factor and set a maximum level for each grade, Chorney said.
“This is the way they’ve done it with protein (content in wheat),” he said.
If DON becomes a grading factor, FDK would remain a grading factor. That’s because even in the absence of DON, damaged kernels affect end-use quality, Chorney said.
KAP president Bill Campbell asked whether adding falling number and DON will result in two more ways to cut what farmers are paid for their wheat.
That could happen, Chorney said. If a wheat sample shows no visual signs of sprouting now it wouldn’t be downgraded, but a falling number test might show end-use quality is subpar. (The reverse could also occur.)
“We think based on the work done by the grain commission and GRL (Grain Research Laboratory) there’s a good basis for scientific-approached grading,” Chorney added.
“We wouldn’t be proposing this if we didn’t think it was a good thing for the industry overall, not just one part of the industry.”
Wade Sobkowich, executive director of the Western Grain Elevator Association, says his member-companies are able to meet end-user specifications with the current grading system. Adding falling number and DON won’t result in more money from buyers. If there are added costs farmers will get less in the end, he said.
The Alberta Wheat Commission has said adding falling number would better reflect the value of each individual farmer’s wheat.
Better price transparency is a potential benefit, Chorney told KAP.
“It’s all about fairness I think, not necessarily to tip the table in favour over another,” he said.
If falling number and DON are added, existing grading factors such as protein content and visual factors such as frost damage, would remain.
Starbuck farmer Chuck Fossay said he isn’t sure about adding falling number. Unless Canada’s Canada Western Red Spring wheats are sprouted they almost always have an acceptable falling number, he said.
“It’s a complicated issue,” he said. “And falling numbers aren’t always the end-all when it comes to grading and what buyers are looking for.
“There’s tradition. What the millers believe, what the buyers want doesn’t always have a lot of relationship to the science, but it’s good to have the science as a backup.”
In an interview later Chorney agreed when harvest conditions are good there’s little concern with falling numbers.
“In those years you may not want to spend a lot of time on this,” he said.
Last fall the CGC added falling number and DON test results when farmers submitted wheat to its Harvest Sample Program. Traditionally, participating wheat farmers received an unofficial CGC grade and protein content.
The new information was well received by farmers, Chorney said. The CGC used money from its surplus to cover the cost.
The CGC uses the information to provide Canadian wheat customers with an early indication of the quality of each year’s wheat crop.
Around 15,000 samples were submitted in 2018 and about half were wheat, Chorney said.