From The Brewers’ Guardian – 1883
The brewing of beer partly from raw or unmalted grain is now successfully accomplished in many breweries, and there is very little doubt that a considerable economy is thus effected; but, in addition to the economy, brewers have to consider the quality of their product. The proper ratio between the dextrine and the maltose can be obtained by a judicious arrangement of mashing heats. Greater difficulty is experienced in obtaining the proper proportion of albumenoids necessary to and suitable for the growth of the yeast cells during fermentation.
There is but little doubt that by the use of unmalted grain we obtain worts poorer in albumenoids, for the process of malting tends to render these constituents soluble, and worts made partly from raw grain are thus generally deficient in albumenoids, and this sometimes creates difficulties during fermentation. Raw grain is rendered much more fit for brewing purposes if it be submitted for a short time to a high temperature on a kiln. This kiln-drying answers a double purpose, it renders some of the albumenoids soluble, thus, to some extent, doing what is done in the malting process, and it also removes the “rawness” of flavour, which is one of the greatest drawbacks in the use of raw grain. The preliminary kiln-drying further develops in the grain a pleasant empyreumatic flavour, which is altogether wanting in undried or strictly raw grain. We anticipate that experience will prove that “raw” grain in the strict acceptation of the term will be found unsuitable for brewing beer, and that it must be previously submitted to a process of kiln-drying or roasting before use.
It will probably be found useful in future for technical writers on brewing to draw a distinction between “raw” and “unmalted” grain.
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