Method for reducing the ash content of wholewheat flour comprises moistening the grain, while it is being conditioned, with an aq. soln. contg. 1-4 wt% alkali metal chloride (A), so that the moisture content of the grain is 16-18, esp. 16.5-17, wt%. - Pref. a 2-3, esp. 2.5, wt% NaCl soln. is used, made up in ordinary tap water or, more pref., in softened water. In a modification, salt-free softened water is used; this also lowers the alpha-amylase activity of the grain.