Lots of Cheese Contains Animal Rennet. Here's How to Shop for Vegetarian-Friendly Dairy.

Many cheeses contain the animal rennet — an enzyme that helps milk separate into curds and whey. That enzyme is typically derived from the stomach of calves killed for veal, so most vegetarians see it as off-limits. Cheesemakers aren’t required to specify on their packages if they’re using animal or vegetable rennet, so you might want to do a little research before buying that next wedge. Here’s what you’ll need to know.

Decode the Label

“Most cheeses are just labeled with ‘milk, salt, and enzymes,’” says Brian Ralph, cavemaster at Murray’s Cheese Shop in New York City. The problem? Those “enzymes” may or may not refer to animal rennet, a traditional cheese-making ingredient extracted from the stomach lining of slaughtered cows, goats, sheep, and even pigs. When in doubt, ask a knowledgeable cheesemonger for cheeses made with veg-friendly alternatives such as vegetable rennet, which typically comes from thistle plants, and microbial rennet derived from fungus, yeast, or mold. (You can safely buy fresh cheeses that don’t contain rennet at all: think cream cheese and paneer.) At the supermarket? Trader Joe’s and Whole Foods both label the source of rennet used in their generic-brand cheeses, many of which are vegetarian. A good cheese shop will also mark it on signs beside the cheese, notes Ralph.

Rethink Romano

As a rule of thumb, be wary of fromage from across the pond. “Most European cheeses are made with animal rennet because these are age-old recipes that have always used animal rennet,” explains Ralph. In fact, according to European Union law, Parmigiano-Reggiano must contain animal rennet in order to use the name. Luckily, you can still find veg versions of Parmesan (and other European-style cheeses) made Stateside. We love Organic Valley Shredded Parmesan and BelGioioso Vegetarian Parmesan, a grate-it-yourself wedge. Into English Cheddar? More and more British cheeses are being made — and labeled — vegetarian. Also, a handful of traditional Spanish and Portuguese sheep’s cheeses, including La Serena and Zimbro, use vegetarian thistle rennet, which has a distinctly briny flavor.

Aim for Organic

Concerned about cheese coming from animals treated inhumanely? Choose organic, when possible: “The bulk of conventional milk production comes from farms that confine their cows to buildings or feedlots during virtually all their productive lives,” says Mark Kastel, co-founder of the Cornucopia Institute. “These cows don’t have the opportunity to exhibit their natural, instinctive behavior, 
such as grazing on fresh grass.” Read the Cornucopia Institute’s Dairy 
Scorecard to see which organic cheese makers provide the most pasture time, prohibit the 
use of hormones, and more. “Most ‘farmstead’ cheese producers, who have a small processing plant right on the farm, go far beyond the minimum required by the USDA organic program,” notes Kastel. Check out the farmstead cheeses at your local farmers’ market, where you can ask directly about farming practices.

Consider the 
Alternatives

There’s no shortage of easy-to-find cheese substitutes these days, with artisanal 
nut-based goodies such as Treeline, Dr-Cow, and Kite Hill appealing to vegans and omnivores alike. “The team at Kite Hill did an amazing thing by getting its cheeses into the regular dairy case at Whole Foods,” says Elizabeth Castoria, author of How to Be Vegan. “It really shows that dairy-free cheeses are new options for any kind of diner.” To make quesadillas, grab melty Go Veggie!, Daiya, or Follow Your Heart. Craving Parmesan? Castoria prefers Parmela, a topping made from almonds, cashews, and nutritional yeast. “And there’s pretty much no point to making nachos without Teese,” she adds. Be sure to check the ingredients: some soy cheeses contain casein, a milk protein.

Quick Trick: Check the type of rennet used in scores of artisanal cheeses at murrayscheese.com and cowgirlcreamery.com. FYI: While most certified-kosher cheeses are 
vegetarian, 
they can be 
made with animal rennet as long as the rennet itself is also certified kosher. Read the label to be safe.

RELATED: I Attended Vegan Cheese Summer Camp and It Moved Me to Tears

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