How do bubbles in coke come into being?

The bubbles of coke are gas carbon dioxide, which is soluble in water according to Henry's law, that is, at a certain temperature, the solubility of gas in solution is directly proportional to the pressure of this gas. In the process of soda production, the factory will add carbon dioxide to the water with a high-pressure device, and the carbon dioxide will dissolve in the water and react with the water to generate carbonic acid.

When pouring into a beverage bottle, some carbon dioxide will overflow from the soda, but because the bottle is sealed and the gas can't get out, the pressure in the bottle is relatively high, and the carbon dioxide content in the soda can always be kept at a high level. However, when the bottle cap is suddenly opened, the air pressure in the bottle quickly becomes lower and the solubility of carbon dioxide becomes lower. So at this time, the carbonic acid in soda is supersaturated, and the supersaturated carbonic acid will spontaneously decompose carbon dioxide, which is bubbles.

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Carbonated drinks (soft drinks) can be divided into fruit juice, fruity, cola, low-calorie and other types, such as cola, sprite, Fanta, 7-up, mirinda and so on.

Among them, fruit juice carbonated beverage refers to natural fruit juice containing more than 2.5%; Fruit-flavored carbonated beverage refers to the spice as the main flavoring agent, and the fruit juice content is less than 2.5%; Coke-type carbonated drinks refer to cola fruit, white lemon, laurel and caramel pigment; Other carbonated drinks: milk protein carbonated drinks, ice cream soda, etc.

Carbonated drinks (soft drinks) subject to food production license management refer to drinks filled with carbon dioxide gas under certain conditions, including carbonated drinks, aerated sports drinks and other specific varieties, excluding drinks that produce carbon dioxide gas by their own fermentation. The content of carbon dioxide in the finished product (volume multiple at 20℃) is not less than 2.0 times.

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