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The type of rennet determines whether a cheese is vegetarian
Whether a cheese is vegetarian or not depends on which kind of rennet is used for its production.
But what exactly is this so-called rennet? Rennet is an enzyme used for coagulating milk. It separates the solid milk particles from the water in the milk, allowing the curd to form. In short, the rennet is responsible for the (firm) consistency of the cheese.
These three types of rennet are most common: animal rennet, microbial rennet, and plant rennet.
Animal rennet is derived from the fourth stomach of newborn ruminants
Animal rennet is the most traditional form. It is an enzyme called chymosin (or rennin) derived from the stomach lining of young ruminants.
To be more precise, rennet is obtained from the abomasum (fourth stomach) of newborn ruminants, where chymosin aids in the digestion and absorption of milk. Because adult animals no longer possess this enzyme, the young are killed at a stage when they are still feeding on their mother’s milk.
Therefore, cheese made with animal rennet is not vegetarian.
Microbial rennet is produced by living microorganisms in the lab
Unlike animal rennet, microbial rennet is created in the laboratory.
It is a coagulant produced by living microorganisms: Yeast, fungi, or mold. These organisms grow in a controlled and monitored environment to yield the correct amount of yeast, fungi, or mold.
Microbial rennet has similar properties to its traditional counterpart and accelerates the coagulation process. In principle, microbial rennet is suitable for both hard cheese and soft cheese.
Plant rennet consists of plants, such as cardoon thistles
Plant rennet, as the name suggests, consists of plants. Popular rennet plants include cardoon thistles, figs, artichokes, and nettles.
The plants are soaked in water to extract a thickening enzyme similar to chymosin.
Rennet-free cheeses exist as well
Cheese does not necessarily have to be prepared with rennet. Rennet-free cheeses are usually cottage cheese, paneer, ricotta, and cream cheese. Those rely on acid (such as vinegar or lemon juice) to help the curdling process.
EU cheesemakers do not need to indicate the type of rennet used
The EU does not require cheese manufacturers to specify what type of rennet they use or whether they use any at all.
However, most do state it in the ingredients list. If you want veggie-friendly cheese, look for cheeses that contain “vegetable rennet” or “microbial rennet.” Some cheesemakers also label their products with “V,” “suitable for vegetarians,” or “rennet-free.”
If you can’t find anything on the packaging, check the manufacturer’s website. There you will typically receive all the necessary information.
Cheeses that NEED to contain animal rennet are mostly protected by law
Nowadays, many types of cheese contain microbial rennet.
Unfortunately, however, there are still a few varieties that are even mandatorily made with animal rennet. These are mostly protected by law and are subject to certain conditions that prescribe the use of this specific rennet. These include some of the most famous cheeses.
Contrary to expectations, the following 7 kinds of cheese are not vegetarian.
1. Parmesan cheese traditionally contains calf rennet
Parmesan is probably one of the most famous and popular cheeses in the world. Unfortunately, it is also one of the cheeses that are not suitable for vegetarians.
Within the European Union (EU), the term Parmesan always refers to “Parmigiano-Reggiano.” Both Parmigiano-Reggiano and Parmesan are “Protected Designations of Origin (PDOs)” under Italian and European law for cheeses produced in certain provinces.
Due to the PDO of Parmigiano-Reggiano, the hard cheese must be produced according to conventional methods.
For the production of traditional Parmesan cheese, fresh milk from certain provinces in Italy (such as Parma and Reggio Emilia), salt, and calf rennet are required. It is not possible to omit the calf rennet. Otherwise, the cheese cannot be called “Parmesan.”
Outside the EU, the name “Parmesan” can be legally used for similar cheeses, with only the full Italian name referring to PDO Parmigiano-Reggiano. In the EU, vegetarian alternatives exist, but they are not called “Parmesan.” Thus, Parmesan always refers to non-vegetarian cheese in the EU.
2. Grana Padano cheese is NOT vegetarian for sure in the European Union (EU)
Grana Padano is another Italian hard cheese protected by PDO under EU law.
Therefore, this cheese can be produced only in certain regions according to a particular process and recipe. The traditional recipe of Grana Padano uses calf rennet.
Since it is protected as a PDO under EU law, selling “Grana Padano” made with another recipe is illegal. Thus, a cheese named “Grana Padano” is not veggie-friendly in the EU.
3. Pecorino cheese may be vegetarian, but Pecorino Romano is not
Pecorino Romano is one of the most widely used, more pungent alternatives to Parmesan cheese. It complements pasta dishes and casseroles perfectly.
The PDO also protects this type of cheese. Since Pecorino Romano is made with lamb rennet according to traditional production methods, this cheese is also not vegetarian.
However, on the bright side, Pecorino Romano is only one type of Pecorino.
The name “Pecorino” itself is not protected and is therefore also used for vegetarian cheese. Tesco, for example, sells a vegetarian alternative.
Thus, a cheese labeled “Pecorino” may be veggie-friendly, while a cheese labeled “Pecorino Romano” is definitely not vegetarian.
4. Queso Manchego is PDO protected, but animal rennet is not a requirement
Manchego is probably the most famous cheese from Spain.
It is solely produced in the wilds of La Mancha in central Spain and is obtained from the milk of Manchega sheep.
The European Union has recognized the “Queso Manchego” as a PDO.
The requirements for Queso Manchego include the production location, the type of milk, the ripening period, and the height and diameter of the cheese.
However, a particular kind of rennet is not specified. Animal rennet is favored but not a necessity. Although most manchego is unsuitable for vegetarians, you may find a vegetarian-friendly version.
5. The recipe for Gruyère cheese requires calf rennet
Gruyère is one of the most popular cheeses for fondue. It derives its name from the Gruyère region in the canton of Fribourg in Switzerland.
Although Switzerland is not part of the EU, Gruyère is protected as a PDO by a bilateral agreement. “Protected Designation of Origin” (PDO) translates as the “Appellation d’Origine Protégée” (AOP) in French. Therefore, the traditional Gruyère is called “Le Gruyère AOP “.
This Gruyère is made according to a specific recipe that contains calf rennet. Therefore, this cheese classifies as non-vegetarian.
6. Gorgonzola's traditional version is non-vegetarian
Gorgonzola is famous for its bluish-green marbling. This soft cheese originated in Italy and is, of course, also protected by the PDO.
As you can already imagine, the traditional version of the cheese is not vegetarian. Gorgonzola originally contains calf rennet.
Luckily, however, many dairy farms now use the cheaper and more readily available microbial rennet to replace the animal rennet.
So you’ll find a vegetarian alternative to Gorgonzola. But it will probably be under a different name because the term “Gorgonzola” is legally protected.
7. Camembert cheese may be vegetarian, but Camembert de Normandie is not
Camembert originated in France and is often compared to Brie because of its appearance and consistency. Fried camembert is a delicious appetizer in many countries.
The good news is that the term “Camembert” is not protected. Thus, there is no ancient non-vegetarian recipe according to which camembert must be prepared. Therefore, this cheese can be totally vegetarian.
But here’s the catch; “Camembert de Normandie” is PDO protected. This cheese comes from Normandy, is made with raw milk, and contains, as you can guess animal rennet. It is a real highlight for cheese lovers, which strict vegetarians, unfortunately, can not enjoy.
Traditional cheeses contain animal rennet while newer versions are prepared with microbial rennet
You can probably see a pattern by now. Many kinds of cheese protected by the PDO are prepared according to conventional methods and recipes.
Most recipes contain animal rennet. However, vegetarians who can do without traditional products can choose from a wide selection of cheeses.
Many manufacturers nowadays replace animal rennet with microbial rennet, as it is cheaper and more widely accessible.
Make your cheese dreams come true: Super Crunchy & Creamy Vegetarian Mac and Cheese
Mac and Cheese are THE perfect comfort food for the whole family. But unfortunately, some variants taste very bland and monotonous. That’s why we decided to spice things up!
We created Vegetarian Mac and Cheese with breadcrumbs tossed in butter. They make the whole dish super crunchy. We also spent a lot of time choosing the right vegetarian cheese. After all, it needs to melt quickly and be flavorful.
We enhanced the whole dish with additional spices, such as smoked paprika and nutmeg. Vegetarian Mac and Cheese have never been so tasty.
Looking for further info? These sites can help:
- What is Rennet? by The Spruce Eats
- Parmesan Cheese: Veg or Not? by Vegetarian Times
