A lacto-vegetarian diet is a diet that abstains from the consumption of meat as well as eggs, while still consuming dairy products such as milk, cheese, yogurt, butter, ghee, cream, and kefir.

Rennet is a complex set of enzymes produced in the stomachs of ruminant mammals. Chymosin, its key component, is a protease enzyme that curdles the casein in milk. In addition to chymosin, rennet contains other enzymes, such as pepsin and a lipase.