Why does milk curdle?

Answer by  martin (522)

Something causes the proteins in it to clump up. That "something" can be an acid, like lemon juice, or it can be a bacterial process, as when milk goes bad.

Answer by  scariapj (346)

The process of milk curdling is happening by the coagulation of protein present in the milk and then it becomes a solid mass. Certain microorganisms and acids can accelerate the process. usually we will use citric acid to make the preparation of curd from milk. Lemon juice is a good source of citric acid and this can be used.

Answer by  trudie1962 (1022)

Milk curdles when the proteins in it coagulate in the presence of an acid. You can observe this by adding a spoonful of lemon juice or vinegar to half a cup of milk. Stir. Let sit for 5 few minutes. This technique is used to make sour milk for baking.