Experiences with beer production by using a one-tank process.

Wittl, G. and Maier, T.W.

Abstract
The paper describes the construction and installation of a brewery at San Joaquin, Venezuela for Cerveceria Polar. The brewery depends entirely on a one tank process and it was hoped to gain significant advantages over the previous conventional procedure. In this system the beer passed from the fermenters to storage, coolers, primary filters, finishing, final filter and then into the Government cellar. In the new system all the stages prior to the primary filter are carried out in a single tank. It reduces transfer and pumping requirements, risk of infection, oxygen pick up, beer losses, cleaning costs and seems to be more attractive in terms of beer flavour and stability. The new equipment automatically led to changes from the old procedure particularly in terms of the time taken to fill a tank, the pattern of yeast pitching, the removal of the yeast and the cooling and filtration patterns. Not surprisingly the beer at first was noticeably different in flavour from the conventionally produced beer. However, the problem was overcome by the following procedures: temperature during filling and the yeast growth period is maintained below 12 degrees C, at the end of fermentation it is allowed to rise above 12 degrees C. The yeast is pitched continuously during filling and the wort is aerated to obtain a uniform level of dissolved oxygen of 6 to 7 mg/litre. Compared to the conventional process yeast quality and performance is much more critical.
Keywords: beer brewing construction cooling fermentation maturation pitching