cheese that has rennet

There are four types of rennet: vegetable/plant, microbial, fermentation-based, and animal.

Vegetable/plant rennet is made from plants like artichokes, nettles, thistles, and dried caper leaves. Microbial rennet uses molds or fungi that have the same coagulating power as animal rennet. Fermentation-based is genetically modified bacterium, fungi, or yeast that can produce rennet enzymes through fermentation, giving them coagulating properties.1

Animal rennet is obtained from the stomach lining, or mucosa, of a ruminant’s abomasum. This is one of the four stomach chambers that ruminants have.2 The main enzyme in animal rennet, chymosin, causes the casein proteins in milk to stick together and form a solid curd while releasing moisture (whey) and trapping the fats and minerals from the milk that are essential for making cheese.3

Over 90% of cheeses made commercially in North America are now produced using fermentation-produced chymosin, plant or microbial as opposed to animal rennet. There are also some molds that naturally produce enzymes that can be used for curdling milk, though these are not used as commonly.4

There is a consensus amongst the scholars that the following types of rennet are ḥalāl:

vegetable/plant, microbial, and fermentation-based. As for animal rennet, there are three scenarios:

1.     If the rennet originates from pig/swine, it will be impermissible to consume.

2.     If the animal was slaughtered in accordance to shariah, then the consensus is that it will be permissible to consume.

3.     There is a difference of opinion in regards to rennet derived from a ḥalāl animal that is not slaughtered in accordance to shariah but the preferred opinion (Imām Abu Ḥanifa) is that it will be permissible to consume.5

Traditional Method vs Modern Method

Traditionally, the abomasum (stomach) is dried and cleaned, then cut into pieces and put into a solution of salt or whey, add vinegar to the solution to lower the pH, and then filtered after some time. Using the traditional method, the rennet would be ḥalāl due to the absence of flesh from the fourth stomach.

The modern method involves the deep-frozen stomach being milled and put into an enzyme-extracting solution. The crude rennet extract is then activated by adding acid; the enzymes in the stomach are produced in an inactive form and are activated by the stomach acid. The acid is then neutralized and the rennet extract is filtered in several stages and concentrated until reaching a typical potency of about 1:15,000; meaning 1g of extract can coagulate 15 kg of milk.6

Although the opinion of Imām Abu Ḥanifa of a ḥalāl animal that is not slaughtered in accordance to shariah (as shown in scenario 3 above) is preferred, some scholars have said it is not applicable here due to rennet becoming contaminated (najas) in the modern method. However, the modern method filters the solution using thousands of litres of water during the process of production, purifies the by-product (rennet)7 and the final product (rennet) does not contain any tissues/remnants from the animal’s stomach.8 Consequently, the final product would be considered pure and ḥalāl to consume.

Therefore, it will be permissible to consume cheese that contains rennet other than that which is derived from pig/swine.

Allāh Ta’āla Knows Best