Beer foam generation:
Beer is a low alcohol alcohol liquor full of carbon dioxide brewed by yeast fermentation with barley malt, hops (Humulus scandens of Dama family, a perennial vine herb, which can make beer have a unique bitter taste and aroma and have the ability to preserve and clarify wort) and water as the main raw materials.
Beer itself is a kind of sparkling wine. Bottled or canned beer is a saturated solution of carbon dioxide, which can be produced during fermentation or added during canning. Under sealed conditions, the higher the pressure, the more dissolved carbon dioxide. When drinking, due to the reduced pressure, a large amount of carbon dioxide will be separated from the beer, forming many bubbles.
In craft beer, there are more organic substances from malt and other raw materials, including polypeptides, proteins and other substances, which can act as surfactants, making the bubbles not easy to break, so the foam is more dense, delicate, stable and lasting.
Role of beer foam:
Enhance the flavor. Carbon dioxide itself has no special taste. However, when it rises to the surface of beer, it absorbs some beer flavor. Therefore, if you carefully taste the foam on the surface, you can still taste a trace of aroma. For the aroma of beer, foam is just like aperture and camera, which can adjust the degree of light entering the lens. An appropriate amount of foam can make the aroma of beer penetrate into our mouth and nose like light; As for the taste, foam is just like the depth of field in the photo. The dense and soft foam increases the overall flavor level and highlights the strength of the beer itself. Therefore, the reason why a glass of beer tastes good is foam.
Keep fresh. The biggest enemy of beer is oxygen. Once it meets the air, beer is easy to be oxidized and deteriorate. Foam can isolate the direct contact between beer and air and prolong the freshness of beer. There is a special protein in the malt for brewing beer, which can capture the carbon dioxide to wrap bubbles, making the foam on the beer surface not easy to break. Before the bubble completely disappears, you can drink the beer in one gulp to taste the freshest and most memorable taste!
Other factors affecting foam forming. In addition to the technology and the amount of carbon dioxide added in beer production, the use of different cups in the same bottle of beer will also affect the amount of foam formation. The most common situation is that the cup is not cleaned, and the detergent left in the cup has a decomposition effect, which accelerates the disappearance of foam. In addition, oil will also accelerate the disappearance of foam.
