Kegs, filling

To prevent contact with oxygen, the beer in the pressure tanks is exposed only to a carbon dioxide atmosphere. The pressure must be higher than the saturation pressure for carbon dioxide. Infection in the brewery is prevented by daily cleaning and disinfection of all equipment in contact with the beer. In the past, almost all the beer left the brewery in kegs, but today most beer is bottled or caimed. The ratio is different from country to country. The growing share of beer in bottles or cans has provided a great need for filling machines with capacities of up to 100,000 bottles or cans per hour. 

The kegging operation is concerned with filling carbonated pasteurized beer into sterile aluminium or stainless steel containers. In British practice. 

Some breweries deliver pasteurized beer, similar to that dispensed into kegs, in tanker wagons directly to the point of sale. The beer is pumped through a hose from the wagon into cellar tanks in the inn cellar. Such cellar tanks (usually about 8 hi or 5 brl) may be aluminium or stainless steel and may be equipped with cleaning-in-place facilities and also with means of maintaining constant pressure. Other cellar tanks of similar size are of mild steel construction and the beer is filled into a disposable plastic bag which acts as a liner to the tank. In such tanks, the beer may be emptied from the bag by applying gas pressure (usually air) within the top of the tank upon the plastic bag. It is not normal to use tank beer systems unless the beer within the tank is likely to be held for 4 days or less. 

Due to their physiological structure, one-way kegs usually neither withstand a hot caustic cleaning or a steam disinfection step. Therefore, sterilization on the filling equipment is not possible, which increases the need for a highly hygienic filling process. 

Drums and containers. Containers used for the transport of polymer dispersions will include small kegs, drums, intermediate bulk containers (one-way or reusable), in-situ or demountable road containers and road and rail tankers. If a sterile emulsion is filled into a sterile, impervious container, microbial growth will not occur but this is very seldom the case and it is often only the biocide that prevents inherent contamination from causing infection. 

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