With apologies to accountants and statisticians, numbers don’t always tell the story. Falling numbers, however, are growing in popularity with farmers around the globe. In an industry where success is equal parts calculation and perspiration, more and more producers are counting on falling numbers to help drive their success.
“Falling number is a widely used and accepted test method for assessing sprout damage in wheat, barley and rye,” said Kristina Pizzi, head of analytical services with the Canadian International Grains Institute.
The falling number is measured by a test that indirectly measures alpha amylase activity. Alpha amylase is an enzyme, present in sprout-damaged wheat, which can significantly reduce grain quality. The falling number refers to how many seconds it takes a plunger to fall through a ground grain sample that’s mixed with water and heated at 100 C.
“When there is little sprout damage, there’s very little enzyme (alpha amylase) activity so the slurry stays thick,” said Pizzi. “As a result, it takes the plunger more time to fall through the sample, giving you a higher falling number.”
When done correctly, the falling number test is quite reliable. That said, there are some factors to keep in mind.
“First, you need a representative sample to ensure accuracy. Because the sample will be ground, you must use proper grinders to get the right particle size in the ground material. You also need to clean the grinder after each sample is ground so that previous samples don’t contaminate subsequent ones.”
Other success factors include correcting for the moisture content of ground wheat, properly weighing the sample, using clean and dry test tubes and ensuring plungers are straight and undamaged.
The test is gaining in popularity due largely to the impact of sprout damage on the quality of processed wheat products.
“The effects are most pronounced in bread where you’ll see a reduction in loaf volume and negative effects on crumb structure,” said Pizzi. “In pasta, the effects of sprout damage are less conclusive. However some believe it can cause production problems such as uneven extrusion, damage to the pasta pieces (i.e. checking) and poor cooking quality in the form of increased cooking loss.”
Since it was first developed in 1960 by Sven Hagberg, the falling number test has seen some enhancements.
“Originally we could only do one test at a time, whereas now we can run two simultaneously.”
There’s also a device called a Shakematic that mixes the sample automatically instead of relying on shaking by hand, leading to more precise results.
Don’t believe your eyes
With the growing reliance on falling numbers among buyers, some are concerned that Canada is being left behind.
“Currently we have a visual grading system for sprout damage in Canada,” said Caalen Covey, business development and markets manager with the Alberta Wheat Commission (AWC). “Since falling numbers are more accurate, international buyers are asking for them, creating a discrepancy between how farmers are graded in Canada and what the global market expects.”
In response, the AWC is calling for a modernization of the grain grading systems in Canada with the inclusion of falling numbers in the Canadian Grain Commission’s (CGC) grading standards.
While the visual system may be faster, it is subject to human error and thus less likely to provide an accurate representation of the sample.
“We’ve received a number of complaints at our office of samples that scored high on the falling number test but were downgraded after visual inspection, sometimes to feed grade,” said Covey.
The use of falling numbers is increasing in Canada; however, Covey said we’re the only country where visual inspection is still the norm.
“Bakers and millers in Canada and other countries want to see falling numbers so they can have a good grasp of what they’re purchasing and compare our samples with others on the world stage.”
Given the reliability and wide acceptance, it’s no wonder the prospects for falling numbers are looking up.