In the United Kingdom, cheese is the largest manufactured milk product on the market, with cheddar beating out all the other cheeses for popularity.
If you’re looking into cheese making, you’ll want to be familiar with animal rennet. Likewise, to make vegetarian cheese, you’ll need to acquaint yourself with vegetarian rennet.
But what is rennet, and where does it come from? How is it used in cheese making? And are all cheeses made with rennet?
If you want answers to these questions, keep reading as we explain everything you need to know about animal rennet and its alternatives.
What Is Animal Rennet?
If you’re familiar with making cheese or following a vegan diet, you may already know that rennet is a significant part of the cheese-making process. Rennet is an enzyme called rennin, which we derive from animals. This enzyme splits the solid parts of the milk from the water content, forming a solid mass.
This process separates curds and whey, where the curds result from coagulation.
- Fun Fact: Rennin is also called chymosin
Cheesemakers can also use microbial rennet and vegetarian rennet to make vegetarian cheese:
- Vegetarian rennet: Is made from artichokes, dried caper leaves, thistles, and nettles
- Microbial rennet: Is made from a mold that can mimic the animal rennet enzyme.
Otherwise, rennet is derived from the cleaned, salted, frozen, or dried fourth stomachs of a few animals:
- Calves
- Goats
- Lambs
There is also bovine rennet, which we get from adult cows, goats, and sheep; however, calf rennet is the most commonly used.
How Was Animal Rennet Discovered?
It’s been suggested that rennet may have been accidentally discovered while our predecessors used the stomach to transport milk from one place to another. It most likely coagulated in the stomach from the heat, forming a cheese.
How Is Animal Rennet Made?
The enzyme rennin is found in young animals still drinking milk from their mother. This enzyme coagulates the milk in the stomach, which keeps the milk in the stomach for extended periods.
Once the rennin has thickened the milk, it takes a more solid form (think: cottage cheese-like), which also remains in the stomach for a long time. This time allows the young animal to digest the proteins.
Once harvested from the calf, cheese makers can use the rennin to replicate the coagulation process outside the calf. Rennet is a commercialized form of rennin.
When using rennet, it’s important to note that the enzyme is only activated once it reaches a temperature of 20 to 40 C. This also means that the enzyme can make several types of cheese with different firmness levels. For example, keeping the curds loose will be better for softer cheeses like camembert, and letting them form into a harder mass will be better suited to harder cheeses like pecorino.
Commercially available rennet is available in liquid, tablet, powder, or paste form. Using powdered or tablet rennet allows the cheese to be stored for extended periods without spoiling.
Rennin is gathered once the animal, typically a calf, has been slaughtered for its meat (i.e., veal). The fourth stomach, also called abomasa, is harvested from the animal as a byproduct and then used for cheese-making.
Where Can I Buy Animal Rennet?
You can buy rennet from brick-and-mortar shops like certain cooking shops, specialty suppliers, and cheese shops. You can also purchase rennet online, which is usually the most convenient of the options as you can have it delivered right to your door.
Liquid rennet might be more challenging to come by in a shop, so you may have more luck sourcing this online.
Experts recommend animal rennet for aged cheeses, as it doesn’t spoil as quickly. Conversely, rennet made from plants can make the product bitter if aged too long.
Once you’ve bought your rennet, you can store it in the following ways:
- Liquid Rennet: Refrigerator for up to a year.
- Vegetarian Rennet: Refrigerator for up to six months
- Tablet Rennet: Frozen for up to three years
This is provided they’re all adequately sealed. True rennet has no flavor and is often indistinguishable from vegetarian rennet.
Finding Rennet in Cheese
We recommend consulting the label if you’re interested in knowing what rennet is in your cheese. However, this may only sometimes be the case as no law states manufacturers have to disclose this information. Although more vegetarian and vegan options are becoming available, more cheese makers include their rennet source on the labels.
Some labels may disclose the exact rennet source, but many may label it “rennet” or “animal rennet.” Vegan cheese has no rennet as it’s not made with dairy, so it needs no coagulation process. Vegan cheese is always displayed on the label, but you can also look for the Vegetarian Society Approved vegetarian and vegan trademarks.
Cheese Made With Animal Rennet
Cheesemakers make cheese in two ways: rennet or acid-coagulated cheese. Acid-coagulated cheese uses acidic ingredients like lemon juice or vinegar. There are several kinds of animal rennet cheese, such as:
- Parmigiano Reggiano
- Pecorino Romano
- Emmenthaler
- Camembert
- Gorgonzola
- Gruyere
- Manchego
- Parmesan cheese
- Grana Padano
- Mimolette
- Vacherin
- Boucheron
Cheesemakers can sometimes skip using rennet if they’re making a softer cheese, and cheese like ricotta doesn’t contain rennet.
Find the Best Rennet Supplier Online
Cheese-making can be a fun hobby or a lucrative career, and knowing what animal rennet is and how it’s used in cheese-making is essential if you want to make your own cheese. In addition, finding an excellent online supplier can make your life so much easier by having your cheese delivered when needed.
If you’re looking for a quality rennet supplier, look no further. Our online shop has everything you need to make incredible cheese. View our rennet selection here.
