Filtration of beer

Fillaudeau L and Carrere H. Yeast cells, beer composition and mean pore diameter impact on fouling and retention during cross-flow filtration of beer with ceramic membranes. J. Membr. Sci. 2002 196 39-57. 

Recent research efforts brought about new and exciting developments in membrane technology, some with direct implications for the membrane filtration of beer. For example, Stopka et al. [21] reported flux enhancement in the microfiltration of a beer yeast suspension when using a ceramic membrane with a helically stamped surface. A relatively simple modification of the ceramic membrane surface resulted in modified hydrodynamic conditions and disturbance of the fouling layer. As compared with a regular, smooth ceramic membrane of the same nominal pore size, the stamped membrane leads to higher flux and lower power consumption per unit volume of permeate at the same velocity of the feed. 

Prevention or minimization of fouling and concentration polarization represents one of the main challenges that confronts membrane processing in general and membrane filtration of beer in particular. Various approaches have been developed to control membrane fouhng and increase the permeate flux in CMF, including membrane selection and modification, boundary layer control, use of turbulence inducers, or pretreatment of the feed. The two main strategies that are currently used in beer CMF are proper membrane selection and boundary layer control. 

The removal of yeast ceUs and haze-forming colloids without unnecessarily removing other components of beer, especiaUy some of the dissolved proteins, is the task and challenge of the beer filtration step. The efficiency of the main filtration of beer is measured by its removal of the yeast cells and by the remaining turbidity of the filtered beer. A common standard is that... 

The typical pore size for the membranes used in final filtration of beer is 0.45 xm. The membrane filter systems are installed in the beer processing line between the bright beer tank and the filling machine. 

Membrane filtration as a technique for final filtration of beer is widely used today, and companies use the term cold-filtered and not pasteurized for selling their products. 

T. Finnigan, R. Shackleton and P. Skudder, Using ceramic microfiltration for the filtration of beer and recoevry of extract. Filtration Separation, 26 (1989) 198-200. 

Fig, 20.21 Flow diagram for two stage filtration of beer from maturation vessel (0 to — 1°C, 32 to 30°F) to bright beer tank. This arrangement is suitable for sterile filtration. 

The beers in Table 11, with the exception of lunch beer, have an original gravity of 6.4—8.1°P. The alcohol content is 0.65—3.4% vol the remaining extract is 3.9—7.1°P. Since the aroma of beers is obtained mainly during fermentation, beers having Htde or no alcohol produced with no or intermpted fermentation are lacking in "tme" beer aroma. Previously aroma was improved through addition of small amounts of yeast (2—10 mg/L) to the unfermented beer. The addition usually takes place just prior to filtration. 

Filtration. Diatomite is used as a filter aid for appHcations with difficult-to-filter soflds to improve permeabiUty of the filter cake, to prevent the blinding of filter elements, and where high clarity is required such as in the poHsh filtration of wine (qv) or beer (qv) before bottling. It is also used in sugar (qv) refining, water treatment, and in the production of fmit juices (qv) and industrial chemicals. 

Representative applications Sterile filtration Clarification/sterilization of beer and Representative applications Continuous culture/cell recycle Filtration of oilfield produced water... 

The lignin content in the filtrate is calculated from the following expression of Beer s Law ... 

Inorganic membranes have also been used in the clarification of other fermented alcoholic beverages such as beer and vinegar in recent years. Two important applications of membrane filtration for beer production are the removal of bacterias and beer recovery from the so-called tank bottoms. They are treated in the following. 

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