Why do lower temperatures and higher pressure help water absorb more carbon dioxide?

The solubility of carbon dioxide in water is governed by physical principles that dictate how gases interact with liquids.

The Role of Pressure

According to Henry’s law, the amount of a gas that dissolves in a liquid is directly proportional to the partial pressure of that gas above the liquid. When a beverage is bottled under high pressure, the increased force pushes more carbon dioxide molecules into the liquid, maintaining a dynamic solubility equilibrium where the gas remains dissolved.12

The Role of Temperature

Conversely, the solubility of carbon dioxide is inversely proportional to temperature. As the temperature of the liquid decreases, the gas becomes more soluble. This occurs because the process of dissolving a gas involves a thermodynamic barrier; as temperatures rise, the energy state of the gas makes it less likely to remain in a dissolved state, causing it to escape the liquid more readily.234

By chilling the liquid during the carbonation process, manufacturers can maximize the amount of carbon dioxide the water absorbs, ensuring the final beverage retains its characteristic sparkle and tangy taste.3