As farmers pick up the harvest pace (finally) they are having to contend with longer queue’s and longer waiting times. All because of falling numbers. Nearly every load in SE Australia is being checked for visible signs of sprouting and being given the definitive test of ‘falling numbers’.
Milling wheat must have a minimum FN of 300 (seconds) with wheat grades and prices cascading lower with lower FN. We thought it a good opportunity to discuss what exactly are ‘Falling Numbers’, how the test works and what the implications are for end users.
Falling Numbers (FN) have a direct correlation to the amount of alpha amylase present in the grain kernel. Alpha amylase is an enzyme secreted from one of the outer seed coat layers (aleurone layer) when the seed gets wet. This enzyme reacts with the starch in the wheat kernel and breaks it down, converting starch into simple sugars. It is the beginning of the germination process, where the seed is using its food reserves (starch) and converting them to sugar as a basic energy source.
The FN test is a standardised test used worldwide to determine if wheat has ‘sprouted’ and to assess the way flour made from that grain would behave in a bakery. Essentially, whole grain with high FN (i.e one that has had no rain on it) forms a thick, doughy paste when mixed with water. The FN test simply measures the amount of time a standardised weighted ‘pin’ takes to move through this paste. The higher the number, the higher the quality flour. Wheat with low FN, will produce a thin, more viscous paste. The ‘pin’ drops through the paste faster – hence the expression low falling numbers.
The test itself can take up to 10 minutes to perform. It was designed to be done in a highly controlled environment such as a laboratory. This is not always the case in a sampling office at the local silo or bunker site. While we’re sure every care is taken, the test can be subject to error especially if equipment is hastily or incorrectly cleaned. Growers can request a second test if a result varies significantly from expected or previous samples.
While the test may not be perfect, it does give us a standard procedure that is more objective than visual assessments.
Whatever the result, wheat with low FN is unsuitable for milling purposes. The degraded starch will result in a dough that has poor elasticity, poor dough strength and poor colour stability. As a result, it is not suitable for pan breads or noodles. Similarly, barley with low FN is not suitable for malting.
What does it mean?
While growers may be lamenting lost milling potential, we are fortunate that demand for feed wheats are very strong. Australian wheat remains very cheap compared to competitor origins and with a low AUD and ocean freight rates decreasing, our reach into SE Asian feeder markets is improving.
Key Points
- Most loads are being given the definitive test of ‘falling numbers’.
- The FN test determines if wheat has ‘sprouted’ and assesses the way flour made from that grain would behave in a bakery.
- While growers may be lamenting lost milling potential, demand for feed wheats are very strong.
Click on figure to expand
Data sources: Reuters, Mecardo
