This is one of the several tricks that German brewers use to circumvent the limitations of the Reinheitsgebot (German Purity Decree). Under the Reinheitsgebot, only water, hops, malt and yeast may be used as beer ingredients. However, unmalted barley can often produce favourable flavours and properties in beer. So maltsters sometimes begin to malt their barley, but then halt the process almost immediately so that only 1/4 of the grain is modified. The Reinheitsgebot does allow the use of this grain, since technically speaking it has been malted. By these means German brewers can take advantage of some of the desirable properties of unmalted grain, since 3/4 of the husk was not modified by the short malting period.