Why does vinegar and milk curdle?

Vinegar and milk curdle because of the reaction between the acid in the vinegar and the protein in the milk. When the acid in the vinegar comes into contact with the protein in the milk, it causes the proteins to coagulate and form curds. The curds are insoluble in the milk, so they separate from the liquid and rise to the surface.

The type of vinegar used can also affect how the milk curdles. Some vinegars, such as white vinegar, are more acidic than others, such as red wine vinegar. The more acidic the vinegar, the more quickly the milk will curdle.

The temperature of the milk can also affect how it curdles. Milk that is cold will curdle more slowly than milk that is warm.

Curdled milk can be used to make a variety of dishes, such as cottage cheese, ricotta cheese, and paneer.