Hot Topic: Falling Numbers in Wheat

If you are an Ontario wheat grower, at one point or another you have probably heard the term, or had your grain tested for falling number.  But, what is a falling number and why does it matter?

What is a falling number in wheat?

A falling number test measures the amount of alpha amylase activity that has occurred within a seed.  Alpha-amylase in an enzyme that degrades the starches within the seed and causes lower end-use quality in baking processes.  In simpler terms, a falling number determines how strong the flour is within a sample of grain.  In any wheat flour sample, there are endosperm, bran and germ parts of the kernel.   Once a seed starts to go into reproductive mode (sprout) alpha-amylase activity increases and starts to turn the endosperm into simpler sugars that the germ can utilize to grow.

Why does falling number matter?

 A falling number is essentially measuring the amount of alpha amylase activity that has occurred in your grain sample. Falling number is very important to any flour mill. For example, in the baking process, as you lose falling number in wheat, the rise of your bread sample begins to lower. In the pastry process you lose the stickiness of wheat (gluten strength) to hold together your baked products. Common numbers for a falling number test in good quality wheat will range from 300-450. The picture below illustrates what starts to happen in your bake quality falling number decreases. The minimum standard for falling number in most situations is 250 for domestic use and 300 for export. 

The risks of low falling number include discounts at a grain elevator or possible load rejection.

What causes low falling number?

Falling numbers are affected by 2 things.   Environment and Genetics.

In wet environments after physiological maturity you will start to see falling number degradation. A sample that stays in the field for multiple rain events after physiological maturity and has preharvest sprouting occur could start to lose falling number. This is a direct relationship to sprouting in wheat. As you find more sprouts, you should see lower falling numbers.

Genetics play an important role as well. Some varieties will genetically have lower falling number. This can be based on a number of factors such as Late maturing alpha amylase (LMAA), genetic background or parentage and more.   

How is falling number tested?

Falling number is tested by grinding wheat into flour and adding water. The “falling number” directly relates on the amount of time it takes for a plunger to fall through this mixture. If it is a higher number, there was more resistance for the plunger to fall through and essentially a better quality of flour.

LOW FALLING NUMBER IMAGE ABOVE – has a watery consistency.  Not sticking together.

Link to falling number video
https://www.youtube.com/watch?v=o5meuWGY0nU

Forward to 2:36 to see effects of low vs high falling number

Knowledge.  Genetics.  Performance.

This is our motto at C&M Seeds. In our 47 years in business and learning through the introduction of new classes of wheat, we have created close bonds with the milling industry. In our genetic evaluation process, we will select based on yield, flour quality, disease tolerance and more. Understanding flour quality of our genetics has been and will continue to be very important to our selection process. Falling number is part of quality, but not the only part. Although sometimes issues can surprise you, we can assure our customers that selection will be made with falling number in mind.

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