Dictionary of the meaning of fishing in winter and drying in summer in chemistry

One step in the traditional production process of "over-mature vinegar" is called "fishing in winter and drying in summer", that is, removing the ice in vinegar in winter (the main component is CH3COOH acetate) and evaporating the water in vinegar in summer.

The temperature drop in winter makes the water in "old vinegar" freeze; Exposure in summer makes the water in "aged vinegar" evaporate, and the quality of solvent in vinegar decreases.