The method is applicable to native and modified starch, to wheat and rye flours and meals and to all cereal grains, the latter after appropriate grinding. The viscosity of a starch-water or flour-water slurry is determined when the starch is gelatinised by heating the slurry, and altered by the action of amylase present in or added to the flour or starch. In this standard the word "flour" also means meals and ground grain (wholemeal).