ARS develops correction for grain quality test

Quality testing is dependent on accurate and repeatable tests that assure a fair marketing system. That also means tests are always tweaked and improved to meet the needs of the industry. The recent advancement deals with a test known as “falling number” (FN). FN is a procedure used worldwide to characterise the suitability of wheat for processing into foods.

Through experimentation in a low-pressure chamber, US Department of Agriculture’s (USDA) ARS agricultural engineer Steve Delwiche and his team at the Food Quality Laboratory in Beltsville, Maryland, developed the correction so that FN results can be expressed at equivalent laboratory conditions, such as what exists at sea level.

Barometric pressure variation caused by laboratory land elevation and local weather patterns means that the thermal conditions of this test can vary, as can the reported FN. Depending on the land elevation of the laboratory performing the FN test, some lots on the margin may fall above the specification, but when evaluated at a different laboratory, for example downriver at a sea terminal, the result may fall on the other side. This can lead to uncertainty and inefficiency in the market system. Commonly, lots with FN below 300 seconds are discounted by $ 0.25 per bushel. A new mathematical correction addresses this variation problem.

Starting in May 2019, USDA’s Federal Grain Inspection Service (FGIS) will implement the correction in a new release of their directive on falling number. Likewise, the American Association of Cereal Chemists International (AACCI) has amended their ‘Approved Method’ on FN as an optional correction.

Source: USDA