A falling number is a measure of enzymatic activity within a grain sample, with a falling number below 300 indicating possible sprout damage prior to harvest. Rainfall close to harvest time may activate alpha-amylase enzymes in the grain seed, which in turn, breaks down the starchy endosperm into sugars that the germ can consume as it begins to sprout. This starch degradation affects the quality of the flour, as indicated by a lower falling number. To calculate the falling number, a slurry of flour and water is placed in a tube and a piston is added. The falling number is the time it takes in seconds for the piston to reach the bottom of the tube. The longer it takes for the piston to reach the bottom of the tube, the lower the alpha-amalyse activity, the higher the falling number, and the better the crop. Conversely, the lower the viscosity, the higher the alpha-amalyse: the rainfall has caused more of the grain to sprout, resulting in lower quality flour. Key take-away: Use flours with falling numbers over 300 when possible.