Chip Cask Treatment.— When sufficiently matured in storage the beer is run or pumped into the chip casks so called because in them wooden chips are placed to retain the sediment produced by the finings. In the chip cask, two properties must be imparted to the beer that it did not possess during storage, namely, life or proper amount of carbonic-acid gas contents and brilliancy. Life is given the beer by addi tion of 8 to 10 per cent of kraeusen (that is, young beer in the first or kraeusen stage of fer mentation). This when added to the old "flats storage beer continues to ferment, and, as the casks are closed, the gas generated gives life to the whole amount of beer contained therein.
For bottle beer, kraeusen made from grape sugar is used, as grape sugar contains no albu minoids as does the kraeusen from regular fer menting worts.
Brilliancy is given to the beer by removing the yeast and other particles in suspension by means of finings made from isinglass. After bunging the cask, a certain pressure only (41/4-5 pounds) is desired and any excess pres sure generated above this is automatically re moved by an automatic blow-off device called the bunging apparatus.
Filtration of Beer.— Although beers will generally become clear in the chip cask if they are left there long enough, they are now almost universally filtered after they have become mod erately fine (clear) in the chip cask. Thereby much time is saved, also a large part of the finings and chips. Furthermore, filtration fur nishes a more brilliant beer than can generally be obtained by chip cask treatment only. Mod ern beer filters, differ considerably in construc tion, but all are alike in that they contain several or many compartments or cells filled with filter mass or pulp (a substance similar to blotting paper) through which the beer is forced. The filter mass or pulp can be used again and again, being washed after each use to remove the beer and sediments it collects dur ing filtration. The operation of filtration is as follows: The bunging apparatus is discon nected and air pressure (15 to 20 pounds) is put on the chip cask and the beer thereby forced through the filter.
Racking of Beer.— From the filter the beer passes to the racking bench which must be placed at a higher level in order to cause a back pressure upon the filter and prevent foam ing. The racking device consists of two or more faucets of which one is always open so as to give a steady flow of beer.
Carbonating.— Beer is often carbonated. This is the mechanical forcing of carbonic acid - gas into the beer by which time, labor, space and cost of chip casks are saved, besides ob taining a more durable beer.
Pitching and In order to prevent the beer in wooden vessels from soak ing into the wood, they are coated on their insides with an inert or insoluble substance.
This is shellac varnish for the large brewery vessels and pitch for the trade packages.
Bibliography.—Relating to American Beers and Malting, and Americanised Methods of Producing English Beers: Studies of American Barleys) (United States Bulletin 124) ; Year Book of the United States Brewers' Association (1909 16) ; Documentary History of the United States Brewers' Association (1896) ; Proceed ings of the Second International Brewers' Congress (Chicago 1911) i Wahl, Robert, and Hemus, Max, 'The American Handy-Book of the Brewing, Making and Auxiliary Trades) (Chicago, 3d ed., 1908) ; in German, Hantke, 'Handbuch fiir den amerikanischen Brauer u. (Milwaukee 1897) ; Wahl-Henius, in (1812).
English Beers and Malting as Practised in England and English Colonies: Sykes, Walter J, and Ling, A. R., and Practice of Brewing) (London 1907) ; Faulkner, Frank, 'Theory and Practice of Modern (London 1888) ; Wright, Herbert E., Handy Book for Brewers' (London 1897) ; Southby E. R., Brewing) (London 1889) ; thatcher, Frank, (Brewing and Malt ing) (London 1898) ; Briant, Lawrence F., Textbook for Brewers) (London 1898) ; Moritz and Morris, of the Science of Brewing) (London 1896).
In German Language: Thausing, Julius E., Theorie und Praxis der Malzbereitung und Bierfabrilcation) (6th ed., Leipzig 1907); Prior, Eugen, (Chemie und Physiologic des Malzes und Bieres' (Leipzig 1896) ; Windisch, W., Chemische Laboratorium des Brauers> (Berlin 1907) ; Fasbender, Franz, Technologie der Bierbrauerei und Malzfabrilcation) (Vienna 1:1.1-90) ; Klocker, Albert, (Stutt gart 1906) ; Jorgensen, Alfred, Mikro organismen der Gaehrungsindustrie) (Berlin 1909) ; Linder, P. Betrieb slcontrolle in den Gaehrungsgewerben) (Berlin 1909) ; Leyser, E., (Bierbereitung' (Stuttgart 1910) ; Lafar, Mykologie) (Jena 1897); Delbrueck, Max, Brauerei Lexikon' (Berlin 1910) ; Hansen, Emil Chr., (Jena 1911).
English Translations: Thausing, Julius E., and Practice of the Preparation of Malt and the Fabrication of Beer' (translated from the German by William T. Brannt, re vised with addition of American methods by A. Schwarz and H. A. Bauer) (Philadelphia 1882) ; Jorgensen, Alfred, (Micro-organisms and Fermentation' (translated from the Danish by Alex. K Miller and A. E. Lcnnholm) don 1900) ; Hansen, Emil Chr., (Practical Studies in Fermentation) (translated from the Danish by Alex. K. Miller) (New York 1896) ; Kloecker, Albert, (Fermentation Organisms) (London 1903).