Physiology and theoretical chemistry have also exerted their influence to bring about the present wonderful development in the science of brewing. During the past few decades the• most complicated processes In the malting of barley, in mashing and in fermentation have been so thoroughly explored that the knowl edge derived from these researches has cre ated a magnificent foundation upon which the maltster and the brewer have been able to build more solidly than ever before in the history of the craft. In this connection, moreover, reference must be made to an invention which has effected more radical changes in the brew ing industry than almost any one single factor, for without it many of the innovations and im provements which are regarded as of such vital importance to-day could never have been made. • This invention is the ice machine, with out which artificial refrigeration upon any ex traordinarily extensive scale, such as exists in many of the big brewing plants at this time, would have been entirely impracticable. It was since 1870 that the imperfect icemaking machine which was shown by the French in ventor, Carre, was regarded as so great a curi osity that persons who were interested in such things traveled long distances to inspect it. To-day, however, conditions have changed so materially that it is only the very insignifi cant brewing establishments that are not equipped with model ice-machines.
One of the distinctly American innovations which have tended so greatly to improve the science of brewing during the past few decades is the new method of collecting and utilizing in its purity all the carbonic-acid gas formed during the process of fermentation. By the discovery of this purely American method it has been possible to abandon the old-fashioned gcraeuser0 process of carbonat ing, which was formerly the only method in general use. In other words, the finished prod uct of the brewery may now be charged with the best and purest natural carbonic-acid gas that it is possible to obtain, and as this method of collecting this by-product of fermentation produces such an abundance of the carbonic acid gas that it may readily be liquefied, there is no reason why every other product of that kind should not eventually be crowded out of the market.
Another distinctively American discovery is the treatment of bottled beer and rendering the same chillproof through the application of the principle of digesting the colloidal albumen of beer by means of proteolytic enzymes in the finishing cask, thus giving the bottled product almost unlimited durability.
As this is not the only occasion upon which the American ingenuity has solved problems relating to the science of brewing over which some of the greatest European authorities have experimented vainly for many years, it is not strange that the brewers of the United States should be able to produce some of the best and, at the same time, some of the most durable beer in the world. Not only have the latest and most scientific methods in brewing that can be credited to the European investi gators been in use in the country, almost from the very moment of their discovery, but several of the processes which have actually originated in this country have since been accepted by foreign scientists as the most rational methods known. In 1893 Professor Delbrueck of Berlin and Professor Schwackhoefer of Vienna were sent to America by their respective govern ments to make a detailed inspection into Ameri can brewing methods. Naturally every facility was offered them, and in their special report they gave the brewers of the United States much of the credit which they deserve for hav ing developed the primitive craft to such a high standard of perfection.
In 1911 an International Brewers' Congress was held at Chicago in connection with an In ternational Brewers' Exhibit of brewers' ma chinery, equipment and materials in which the United States Agricultural Department was conspicuously represented.
Revised by ROBERT WAHL.