system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do some non carbonated, sealed drinks increase in pressure when you shake them?

For example, shaken coffee or milk. When you open the container, it releases pressure. Where does the increase come from? It doesnt happen with water. It seems to be more likely if the liquid can produce bubbles when shaken. The gas in the container is the same as before shaking, why does the pressure increase?
gpt
Gases dissolve into liquids at varying amounts depending on the liquid and gas. Gases also escape liquids based on the pressure of gas above the liquid. A bottle of juice at rest has a volume of gas on top, a volume of liquid on bottom, and a surface area of interface in the middle, all at equilibrium. When you shake a bottle, you produce more surface area which allows dissolved gas to partition from the liquid into the bulk gas phase. When you stop shaking there is exists a greater amount of gas in the bulk gas phase, which results in a greater pressure. That pressure of gas either escapes when you open the bottle, or is forced back into the liquid to establish the initial equilibrium.