STUDIES IN BARLEY AND MALT XXII. EFFECT OF ELEVATED TEMPERATURES DURING MULTIPLE STEEPING*

Conditions have been found whereby, through multiple steeping procedures, green malt ready for kilning may be manufactured on a small scale from a six-rowed variety of barley, Olli, in 3 1/2 days. In the case of a two-rowed variety, Proctor, the corresponding time is 4 days though this may be reduced to 3 1/2 days if the grain is treated with gibberellic acid immediately after the first period of steeping. It is found that the induction of water sensitivity effected in barley by the initial steep depends on the temperature of the steeping treatment, rather than on the moisture uptake during steeping. Optimum conditions for the initial steep are those which soonest raise the moisture contents of the barley varieties Proctor and Olli to minimum values of 32% and 38% respectively, provided (a) germinative energy is not impaired, and (b) induced water sensitivity does not exceed approximately 35%. A study of the changes which occur in the properties of the grain as measured by standard analytical methods during malting when the multiple steeping procedure is employed shows that such technique simply accelerates the process of modification which takes place in barley under conventional conditions of malting. Individual varieties of barley are placed in the same order of malting quality, whether malted conventionally or by multiple steeping techniques.