Many cheeses in the US are vegetarian, as they use a microbial rennet source. Still, there are places that use animal-derived rennet sources. Products made with animal-derived rennet sources are not vegetarian. Rennet that comes from an animal is from the stomach lining of a slaughtered cow, sheep, or goat. Some places also use rennet derived from slaughtered pigs. So to answer the question that many people have:
Are Cheetos vegetarian? Do they use animal or microbial sources of rennet?
I contacted the company directly to ask them if Cheetos are vegetarian/what the origin of the enzymes are. Here's the response I got back from them today:
"Thank you for writing. Animal enzymes are used to make the cheese for all varieties of Cheetos.
Most of the cheeses in our seasonings are made with animal enzymes, similar to cheeses sold in the grocery store. If you want to avoid these enzymes, you might want to avoid our snacks that list "cheese" and "whey" as ingredients. Only a few snacks have animal flavors and they will be listed on the ingredient statement, not hidden under "natural flavors."
The snacks on our kosher list are free of animal flavors and animal enzymes. You'll find this list in the "Snacks, Facts & More" (from the drop-down menu at top right of our home page), then "Special Dietary Needs."
Our non-seasoned, salted-only snacks, such as Lay's Classic, Ruffles Original, Fritos, Santitas, Tostitos, Original SunChips and Rold Gold Pretzels, do not have enzymes of any kind.
Thank you again for choosing Frito-Lay snacks. We will continue to provide the information you need to make safe, great-tasting choices."
So there you have it. Cheetos are not vegetarian, because they use animal-derived rennet in the cheese. Furthermore, no Frito-Lay snacks that contain cheese are vegetarian, so that goes for their chips and other snacks as well.
The good news is that they do make plenty of vegan snacks you can choose from, including their classic chips, ruffles, fritos, etc. You can find a list of all their snacks that don't contain any animal flavors or enzymes here (their Kosher list). From the looks of that list there are many options to choose from that do not contain animal rennet and that appear to be vegan, so you shouldn't miss skipping the Cheetos. Plus, you can try the vegan alternative Earth Balance Vegan Aged White Cheddar Puffs. They are great and you don't have to worry about any type of animal rennet (or other animal ingredients) being in them!