Is Mozzarella Halal? Rennet, Enzymes & Labels Explained

Mozzarella is a stretched-curd cheese. It is made from cow's milk or Italian buffalo milk, and in some areas from sheep's or goat's milk ^[1]. The milk is set into curd, drained, heated and then stretched and kneaded into a smooth, elastic cheese ^[1].

There are two main kinds in US stores:

• Fresh mozzarella, sold in balls in brine or whey.
• Low-moisture mozzarella, the firmer block or shredded cheese used on pizza. Some of it is made with citric acid or by acidifying the milk directly ^[1].

The milk itself is halal. The question is the agent that turns the milk into curd.

Traditional rennet comes from the stomach lining of young calves ^[2]. That is where the halal question comes from: if the calf was not slaughtered Islamically, its rennet raises a concern for many scholars.

Today, though, most cheese does not use calf rennet. Animal rennet is now used in less than 5% of US cheese ^[2]. Most cheesemakers use one of these instead:

• Fermentation-produced chymosin (FPC). The enzyme is made by microorganisms in fermenters. It held about 80 to 90% of the US and UK markets by 2021 ^[2].
• Microbial rennet. Made by molds and suitable for vegetarian cheese ^[2].
• Vegetable rennet. Made from plants like thistle or fig, though commercial "vegetable" rennet is often mold-based ^[2].

Cheese made with FPC can be certified halal ^[2]. One exception to watch: sheep's milk mozzarella is traditionally made with lamb rennet ^[1].

The Qur'an forbids carrion, meaning animals that died without proper slaughter ^[4]. Scholars disagree on whether rennet taken from such an animal counts as part of the carrion.

According to an IslamQA summary, the apparent view of the Maliki, Shafi'i and Hanbali schools is that this rennet is impure, so the cheese should be avoided ^[3]. Imam Abu Hanifa, and one narration from Imam Ahmad, held that the rennet stays pure, so the cheese is allowed. Ibn Taymiyyah preferred this second view ^[3]. The same answer says an ordinary Muslim may follow a scholar who holds either view ^[3].

If you follow the stricter view, the safest choice is mozzarella made with non-animal enzymes or carrying a halal certification.

US labels often just say "enzymes" without naming the source. That word alone doesn't tell you whether the enzyme came from a calf or a microbe. Here is what helps:

• Halal symbol. A certifier's logo is the clearest answer.
• "Microbial enzymes" or "vegetable rennet." These point to a non-animal source ^[2].
• Kosher symbol. Nearly all kosher cheeses use microbial rennet or FPC ^[2], so it is a useful clue. Kosher and halal are still different standards, so see our kosher vs halal guide.
• Ask the brand. If the label only says "enzymes," the customer service line can usually tell you the source.

Recipes and suppliers change, so check the current package each time. For more on the enzyme question, see rennet and enzymes.

Most mozzarella you eat comes on pizza. There, the cheese is usually less of an issue than the toppings and the kitchen. Ask whether the pizzeria uses pork toppings like pepperoni and whether they share pans or cutters. Our pizza and cheese pizza pages cover what to check.