TECHNOLOGY AND CHEMISTRY. The two preced ing paragraphs outline briefly the processes of malting and brewing. To describe the technology and chemistry of these processes in non-technical language is rather difficult. Briefly enumerated, the technical considerations which call for the most part icular attention are: (1) The nature and quality of the grain used; (2) the malting of the grain: (3) the temperature at, the com meneement of mashing and again at the begin ning of fermentation; and (4) the quality of the water used. It is impossible to enter into these teehnical questions in detail here, hut some brief indications of their character may he given. Re garding the choir'. of barleys for brewing, they should be thoroughly ripened and should be care fully harvested and handled to preserve the skin or husk of the kernel, since when the kernel is bruised or has its skin broken mold is likely to attack it and cause trouble, if not disaster, in malting and brewing. The precautions to be taken in malting have already been described. Regarding the incipient temperature of tile mash and of the wort at the eta ttttt eneement of ferm•n tation, it can only be said here that it is held to be of prime importanee, and if not accurately controlled may result in spoiling the brew. In
respect to the water used, the principal require ments arc that it should be absolutely pure and should be somewhat 'hard,' that is, it should contain lime salts. The principal chemical no tions occur during malting, when the mash is being made, and during fermentation. During malting the albuminous substances in the grain are changed to a substance known as diastase, which has the power to change the insoluble starch of the grain into dextrin. and then into glucose or grape-sugar, both of which substances are soluble in water. This conversion takes place during the steeping of the mash. During fermentation the glucose which has been formed in steeping is decomposed by the action of the yeast into alcohol and carbonic-acid gas. Va rious minor chemical reactions occur during all of these processes, for the explanation of which special treatises on brewing and fermentation may be studied.