Parmesan cheese isn't made like other cheeses and it's leaving people sick

People are just realising how parmesan cheese is actually made - and it's grossing cheese fans out.

The fifth most popular cheese in the world, parmesan - short for Parmigiano Reggiano - is loved by many, and is often the go-to cheese of choice to load on top of pasta dishes.

But, in case you didn't know, parmesan isn't made entirely like other cheeses.

However, after heating, a product called rennet is added to curdle the mixture. It's then left to set, and becomes the parmesan we know and love.

"Today years old when I found out Parmesan cheese is made from baby cow’s stomach & I could go cry. I’m just gonna have to go full vegan at this point," they wrote.

The Twitter user is referring to the product rennet, which is an enzyme found in the stomach lining of calves and goats.

People on Twitter were pretty horrified by the tweet, while others pointed out that a different method is often used.

One person wrote: "Horrifying! Why are we eating baby anything as a species."

While another said: "Wow I had never heard that! Dairy is scary fr."

And a third added: "Yup, I'm sure you'll notice it now but if you look at restaurant menus, anything with parmesan won't even be labelled as vegetarian."

However a fourth commented: "Most rennet today uses genetically-engineered yeast and bacteria in its production, rather than calf stomachs.

"There are obviously still some products that use calf stomachs (as a matter of tradition), but most mass-produced cheese uses GMO rennet."

And a fifth wrote: "Most cheese is now made with chymosin from bacterial sources, rather than animal rennet."

"Thats not majority of parmesan cheese today, most are made without the veal stomach just gotta double check ur label," said a sixth.

Many manufacturers now use vegetarian rennet, which can be produced in two different ways.

One way of harvesting a similar, animal-friendly version of rennet is by using certain moulds to produce a similar enzyme. This is done by fermenting the mould to produce microbial rennet - which is the most common in the UK.

Otherwise, certain other organisms can be genetically modified to create chymosin to be used in a similar way.