The purpose of beer filtration mainly has the following three points:

(1) to remove the suspended matter in the wine, to improve the appearance of beer, so that the beer clear and transparent, full of luster;

(2) to remove or reduce the beer appears turbid precipitation of substances, such as polyphenols and proteins, etc., to improve the colloidal stability of beer;

(3) to remove yeast or bacteria and other microorganisms, improve the biological stability of beer. Beer filter can be divided into beer filter clarification, non-biological stability treatment and biological stability treatment.

In the clarification of beer, the current domestic commonly used technology centrifugal separation, diatomaceous earth filtration and cardboard filtration, the use of the main equipment are centrifuges, diatomaceous earth filter (divided into box-type diatomaceous earth filter, candle Diatomite filter, the level of disc diatomite filter), plate filter and so on. In the non-biological stability of the treatment, the beer to add PVPP, silica gel, tannin, protease and other applications are more extensive. In the biological stability of the treatment, the main use of sterilization pasteurization, sterile filtration is a sterile membrane filtration technology.

1, centrifugal separation

As the beer fermentation liquor viscosity is high, the particle diameter is very small, the natural settlement rate is very slow, using centrifugal instead of natural settlement, the separation rate is greatly improved. Centrifuge is generally not used alone,

Mostly in combination with diatomaceous earth filtration. When the turbidity particles in the fermentation broth too much first with a centrifuge for pre-clarification, and then filter with diatomaceous earth filter. But the centrifuge pre-clarified

There are the following problems:

(1) due to high-speed rotation and air friction, so that has cooled the temperature of the beer, carbon dioxide leakage caused by the bubble so that the next step to become difficult;

(2) in the process of clarification of beer will be mixed with a certain amount of oxygen, thus affecting the quality of beer;

(3) high-speed operation of the centrifuge noise, high maintenance costs.

2, diatomaceous earth filter

Diatomaceous earth filtration is currently the most widely used brewery filtration method. Diatomaceous earth is a marine single cell algal plant remains, China's diatomite mineral resources in the forefront of the world. The main component of diatomite is amorphous silica. At present, most of the primary filter of beer used in the filter aid is diatomaceous earth or diatomite and quartz sand mixed particles. The use of diatomaceous earth filter can be clear beer, turbidity below

0.6EBC, microbial content is very low. The advantages of diatomite filtration are: constantly changing the filter bed; filtration speed, yield; surface area, adsorption capacity, can filter 0.1 ~ 1.0μm below the particles; reduce the wine loss of about 1.4% to improve the production operating conditions.