How to Avoid Exposure of Beer to Oxygen During Fermentation

The oxidation process of beer will produce a variety of adverse factors，including the following points，which intensifies the formation of cold turbidity and oxidative turbidity, affects the abiotic stability of beer, and shortens the storage period of beer.the flavor changes, resulting in bad tastes such as stale taste and astringent taste.After the oxidation of polyphenols, the color of beer is deepened.Oxygen can also increase the diacetyl of finished beer, causing beer to produce rancid rice and creamy taste.

Beer brewing water refers to water for saccharification, gelatinization, and water for washing lees. If the oxygen content is high, it will consume a large amount of reducing substances in mash or wort. Using deoxygenated water as brewing water will reduce saccharification Process oxygen intake.Appropriately reducing the stirring times and stirring speed will reduce the oxygen inhalation.During the washing process, the washing water should be added in time before the washing layer is exposed to the liquid surface, so as to avoid the large area contact between the washing layer and oxygen, which will reduce the oxygen inhalation.

Wort is easily oxidized at high temperature, so the wort boiling time should be reasonably controlled, not too long, generally controlled within 90 minutes, preferably within 75 minutes. Excessive boiling makes the wort taste rough and increases the color of the wort.

Shorten the time for wort to be pumped from the boiling pot to the whirling sedimentation tank; under the premise of ensuring the whirling sedimentation effect, shortening the sedimentation time will reduce the heat load of wort and reduce the oxidation and reduction substances of wort Loss.

The mash or wort is sent from the bottom of each tank, which will reduce the inhalation of oxygen in the process of transporting mash or wort.During the saccharification operation, after the addition of materials or sampling is completed, timely closing the manhole door of each saccharification tank will reduce the inhalation of oxygen.

When the mash or wort pumping is about to end, stop stirring in advance or reduce the stirring speed; when the mash pumping ends, turn off the mash pump in time to prevent the mash from inhaling a large amount of oxygen.