Rennet

This refers to a set of enzymes from the stomach of young ruminant animals. It coagulates milk, turning it into a solid (some form of cheese). It causes milk from the animal’s mother to coagulate in the animal’s stomach and digest more slowly.

Rennet is harvested from the stomachs of unweened animals and is used in the cheesemaking process. There are other alternatives as well: synthetic and vegetable.

Rennet is often referred to as an “enzyme.” However, more accurately, it’s a set of enzymes. The main enzyme that begins the curdling process is chymosin.

I looked it up on Amazon. It’s not expensive. Small bottles can be purchased for about $15, and it comes in tablet and powder form as well. You apparently use very small amounts – fractions of a teaspoon.