Beer Fermentation Turbidity Solution

Hazy beer is a beer that contains a specific amount of live yeast in the finished product, and the turbidity unit is 2.0-5.0EBC. Beer designs require specific turbidities (except for wheat beers, turbid IPAs, and some stouts). Unless there are special circumstances, beer is still distinguished by color and transparency. Next, let's introduce the biological turbidity and abiotic turbidity of beer.

Biological Turbidity: The fermentation process can contaminate a variety of other micro-organisms, resulting in a deadly increase in beer temperature.

The Pu value for complete beer sterilization is lowered, the water temperature level of the sanitation device is lowered or the water spray has dead angles, which cannot eliminate yeast and polluting microorganisms. With biological turbidity, strict procedural hygiene is entirely preventable.

Abiotic Haze: The compounds that cause abiotic haze in beer are mainly healthy proteins, peptides, polyphenols, polysaccharides and hop resins. The main types of turbidity are protein polyphenol turbidity, dextrin turbidity, polysaccharide and protein-polyphenol complex precipitation, inorganic precipitation, hop resin turbidity.

The healthy protein in beer mainly comes from malt, and the healthy proteins that cause beer turbidity include gliadin and β-globulin; the polyphenols in beer come from bark and hops, and the polyphenols that cause beer turbidity generally come from yellow of alkyl hydroxyl groups. Healthy proteins and polyphenols are often clouded by oxidation and aggregation of large amounts of iron. According to its development, it can be divided into the following situations:

Real healthy protein turbidity (hygienic turbidity): Since the pH of beer is similar to the isoelectric factor of healthy protein, and the content of healthy protein is high, the water film of healthy protein in beer will be affected in the whole process of sanitation and home heating. damaged.

Cold turbidity: Beer will definitely lose luster and cloudiness when stored at low temperature (0°C), but when the beer is heated to 20°C or higher, its turbidity will definitely decrease or disappear, which is called cold turbidity or relatively constant turbidity Spend. Because wort and beer contain additional beta-globulins and delta-gliadins, which form hydrogen bonds with water at ideal temperature levels and are water soluble. When beer is heated above 20°C, the weak hydrogen bonds break. The luster of the beer fades and the healthy protein combines with water to form a liquid.

Permanent turbidity (oxidative turbidity): After the beer is stored for a certain period of time, the polyphenols, anthocyanins and healthy proteins in the beer undergo oxidative polymerization to form oxidized polyphenols and also polymerize healthy proteins. The two polymers are covalently bonded to form larger fragments of healthy protein-polyphenolic polymers that rise out of the beer at a faster rate, initially cloudy, then stop and gradually reach the vessel's all-time low, A layer of thin and loose fragments is formed, and the wine body gradually returns to clarity and transparency. This turbidity is irreversible.