In the fermentation and storage of beer, different quantities of yeast and tank bottoms are produced, depending on the process used. In most cases, these still contain a substantial quantity of beer, which must be recovered in economical processes. One of the most frequently employed methods of recovering beer from the tank bottoms is the use of separators and decanters. When these are used, a good quality of the recovering beer is achieved when the yeast and tank bottoms are processed whilst as fresh as possible (e.g. directly from the fermentation tank). However, if intermediate storage is necessary, the collecting/buffer tank should be capable of cooling and contain a CO₂ atmosphere.