It's true! In fact, most cheeses aren't vegetarian, especially European ones and those that are modeled after Old World recipes and techniques. But don't start cheese fretting yet — there are tons of great vegetarian cheeses, and with our recommended list in hand you won't go wrong.
First things first: Cheese becomes cheese through a process called acidification. It's a process that coagulates and isolates the solids in milk, which then allows the cheesemaker to manipulate those solids into various cheese styles.
Most cheeses are coagulated with an enzyme known as rennet, which is derived from the stomach lining of unweaned young animals; this enzyme helps them digest their mother's milk. In cheesemaking, that same enzyme breaks down the protein chains in liquid milk. Generally speaking, cow milk cheeses use calf rennet, goat cheeses use kid rennet, and sheep cheese uses lamb rennet. Rennet is also sometimes extracted from the lining of pigs' stomachs. Rennet usually comes in powder or liquid form, and an incredibly small amount is used to coagulate a very large amount of milk.
Vegetarian cheeses, on the other hand, are coagulated with either a synthetic, or microbial rennet, derived from mold or yeast, or with a vegetable- or plant-derived rennet, which would typically come from the cardoon thistle plant.
Rarely would you ever be able to taste a difference in taste between the two, and truly great cheeses can be made from both types of rennet.
Here's a list of some of our very favorite vegetarian cheeses:
Related: Help Me Find Some Healthy, Satisfying Vegetarian Recipes
Nora Singley is an avid lover of cheese, and for some time she was a Cheesemonger and the Director of Education at Murray's Cheese Shop in New York City, where she continues to teach cheese classes for the public. She is currently an assistant chef on The Martha Stewart Show.
(Image: Flickr member nshepard licensed under Creative Commons)