The prolonged and rain impacted harvest season across much of our region has created many challenges, including a slow harvest pace, high moisture wheat, reduced color or vitreous kernels, and a larger than normal share of the crop is also showing low falling numbers. This has added marketing uncertainty for both producers and end-users, and required additional quality testing.  Producers and grain handlers have raised questions regarding the falling number quality test, what the values mean, and how to manage low FN wheat. 

Falling numbers are an indication of the level of alpha-amylase enzyme activity in a sample of grain or flour.  The alpha-amylase enzyme activity is a natural process within the plant, and it is the process by which seeds begin to germinate and grow when planted, if exposed to enough moisture.  The enzyme helps to break down the starch within a wheat kernel into sugar and compounds essential for metabolic activities needed for germination and seedling growth.  While this process is beneficial for the developing wheat plant, too much starch degradation can cause significant challenges when flour is used for baked products, or semolina for pasta products.  Flour made from grain with low FN has reduced water absorption and mixing strength, and it produces a sticky dough. Bread made from flour with low FN can result in lower loaf volume, poor crust strength and crumb texture, and create loaves that may collapse.  The sticky dough and reduced consistency in baked bread structure are especially challenging with today’s high speed and highly automated processing equipment.  Pasta products made with semolina from grain with low FN have reduced shelf life due to poorer structure, are less firm when cooked and can result in greater cooking losses.

Typical contract specifications from domestic and international customers are a minimum of 300 seconds, with some international customers even specifying a minimum of 330 seconds.  These have been in place for numerous years, but obviously they do not become marketing constraints unless adverse weather impacts the crop.  The falling number value is based on an index of the amount of time it takes a plunger to drop in a test tube of gelatinized ground wheat or flour.  The longer it takes, the greater the resistance of the starch and less enzyme activity.  A shorter time reflects higher enzyme activity, and more starch conversion to sugar.  Industry research has shown that a high falling number value (above 300 seconds) indicates minimal enzyme activity and sound quality wheat.  A low falling number (less than 250 seconds) indicates substantial enzyme activity. 

Blending of low and high falling number wheat poses significant risk since the blend equation is not linear, as it is with protein, or other factors.  It is an exponential equation.  This means a 50/50 blend of 350 second and 250 second FN wheat will not equal 300 seconds, it may remain closer to 250 seconds.  Due to this fact, segregation of low FN wheat is critical to protect the higher market value of sound wheat.

Milling market outlets for low falling number wheat are more limited, and bring a lower value than the traditional domestic and international markets which purchase our high protein hard red spring wheat and durum.  Many of our customers purchase wheat from this region for blending with lower protein, weaker gluten wheat to upgrade the quality of end-products, or for using in the production of specialty products.  The adverse impacts of low FN on flour and semolina properties negate the benefits of high protein and strong gluten properties typically found in wheat from this region.  While some minor adjustments in contract specifications for FN may happen with a few customers, depending on the overall availability of sound wheat, ultimate price spreads, and end-product needs, historically it has not happened on a large scale. The adverse impacts on flour quality and final product performance, combined with the significant blending challenges with low and high FN wheat, tends to push low FN wheat into lower valued milling and feed markets.

Managing the quality impacts which adverse weather has dealt both producers and grain handlers this harvest season will require extra diligence in testing, segregation and determination of the best market value.  Testing protocols must ensure that equipment is properly calibrated, test tubes are thoroughly cleaned between samples, and the new FGIS directive (May of 2019) is implemented.  Falling number tests can produce more variable results than tests for protein, moisture and test weight due to the nature of the alpha amylase enzyme, so adhering to the protocols and official guidelines for the test are critical.

For further background on the issue please go to the North Dakota Wheat Commission website and look under the Grower section and Issues to find some extension publications, as well as the most recent FGIS directive regarding falling number.  The website is