Thus it appears, that the process of malting is nothing else than causing the barley-corns to germinate, and stopping that process before the green leaf makes its appearance. A quantity , of roots are formed, which are afterwards rubbed off and separated, and the weight of which amounts to about four per cent, of the grain malted. The kernel of the grain undergoes a remarkable change by this process. It consists almost entirely of starch; but it was agglutinated in the grain, so as to form a solid and very firm mass; whereas, in the malt, it is quite loose and mealy. Hence it would appear that the glutinous and mucilaginous matter of the barley-corn is chiefly employed in forming the roots ; and that this is the purpose for which it was laid up in the grain. How far the starch is altered does not appear. It is probable that it has undergone some change. Malt has a slightly sweet taste, much more agreeable than the taste of the raw grain, without any of that strong and cloying sweetness which distinguishes wort. But the most distinguishing character of the starch of malt is the ease with which it dissolves in hot water; though cold water does not act upon it sensibly. Whether this property be peculiar to the starch of barley, or be induced by the malting, we cannot say. We conceive it probable, that barley-starch is more easily soluble in water than wheat-search, from the \ease with which raw grain is constantly employed by distillers to form their worts. In its other chemical characters, the starch of barley-malt agrees with that of wheat-starch.
We should err very much, however, were we to suppose that the whole kernel or starchy part of the malt is dissolved by thé hot water used in brewing. At least one-half of the malt still remains after the brewing is over, constituting the grains, which are known to constitute a most nourishing article of food for cattle, and therefore to contain much more than the husks or skin of the malt-corn« 100 lbs. of malt from different kinds of grain, after being exhausted as much as usual of the soluble part of the kernel by hot water, were found to weigh as follows :—
100 lbs. of raw grain being converted into malt, and the soluble part of the malt extracted by hot water, the residue weighed,—
Scotch big, 53*500
In another set of experiments, 100 lbs. of malt left the following residues :—
Scotch barley, 56*9
100 lbs. of the raw grain being converted into malt, and the soluble part of the malt extracted by hot water, the residues weighed,—
Hence we see, that in all these cases the bulk of the malt was very nearly the same as the previous bulk of the barley before it was malted.
In another set of experiments, 100 lbs. of malt left the following residues:—
English barley, . . . 54*0 lbs. Scotch barley," . . . 56*1 Scotch Big, 56-6
100 lbs. of the raw grain being Sonverted into malt, and the soluble part of the malt being extracted by hot water, the residues weighed,—
English barley, . . . 54*63 lbs. Scotch barley, . - . . . 56*09 Scotch big, 56-59
Here also the bulk of the malt differed but little from that of the raw grain. The first of these sets of experiments was made with grain of the best quality, the second with grain of the middling quality, and the third with grain of the third quality.
It is probable that an additional portion of the kernel would be dissolved if the malt were ground finer than it is customary to do. The reason for grinding it only coarsely is to render it less apt to set. But this object might be accomplished equally well by bruising the malt between rollers, which would reduce the starchy part to powder, without destroying the husk. This method, indeed, is practised by many brewers, but it ought to be followed by all.
Was this article helpful?