Is Rennet Halal? Animal, Microbial & Vegetable Rennet
It depends on the source. Microbial and plant rennet are accepted as halal [4][8], and so is rennet from a halal animal slaughtered Islamically [5]. For rennet from animals not slaughtered Islamically, scholars differ. Imam Abu Hanifa held it pure, while most Shafi'i and Hanbali scholars hold it impure [3]. If you're unsure, ask a scholar you trust.
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What the schools of thought say
| School | View | Source |
|---|---|---|
| Hanafi (Imam Abu Hanifa) | Rennet from a halal animal is pure even if the animal was not slaughtered Islamically, because the rennet does not die with the animal. This does not extend to anything from swine. | [3][4][7] |
| Hanafi (Imams Abu Yusuf and Muhammad, and many later muftis) | Such rennet is impure because it touches stomach fluids that become impure at death. Darul Ifta Birmingham advises this cautious view for cheese from non-Muslim countries, and a South African fatwa says modern rennet is impure by all three imams' standards. | [5][6] |
| Maliki | Sources differ. Islam Q&A counts the Malikis with the majority who hold non-zabiha rennet impure, while Darul Ifta Birmingham reports Imam Malik held it pure. | [3][5] |
| Shafi'i | Rennet from an animal not slaughtered Islamically is impure, so cheese made with it is not permissible. | [3][4] |
| Hanbali | The apparent school view is that such rennet is impure. One narration from Imam Ahmad holds it pure, and Ibn Taymiyyah considered that view more likely correct. | [3] |
| IFANCA (US certifier) | Microbial and plant enzymes are halal. Animal enzymes are halal only when taken from halal-slaughtered animals. | [8] |
What rennet is
Rennet is an enzyme preparation that makes milk curdle, the first step in most cheesemaking. US regulations describe animal rennet as an extract from the fourth stomach of calves, young goats or lambs [1]. Bovine rennet comes from adult animals of the same kinds [1].
Today much of the enzyme is made without animals. US rules allow chymosin produced by fermentation, using harmless microbes such as Aspergillus niger or Kluyveromyces yeast that carry the gene for the enzyme [1]. There are also microbial rennets and plant-based coagulants [7].
Why it matters for cheese and whey
Rennet ends up in cheese, and its by-product, whey, ends up in protein powders and snacks. US cheese standards allow rennet or other clotting enzymes of animal, plant or microbial origin [2]. The label may simply say "enzymes" without saying which kind [2].
So "enzymes" on a US cheese label doesn't tell you the source. Some traditional cheeses must use animal rennet. IslamOnline notes that authentic Parmigiano Reggiano is made with animal rennet [4].
See our pages on cheese, parmesan, whey protein and enzymes.
Why scholars disagree
Everyone agrees that rennet from a halal animal slaughtered Islamically is fine [5], and that microbial or plant rennet is fine [4]. The debate is over halal animals, like calves, that were not slaughtered Islamically.
- The permissive view comes from Imam Abu Hanifa and one narration from Imam Ahmad. They held that the rennet stays pure because it does not die with the animal [3]. Ibn Taymiyyah leaned toward this view and cited reports from the Companions in its support [3].
- The stricter view is held by most Shafi'i and Hanbali scholars and, per Islam Q&A, the Malikis. They treat the rennet as part of a dead animal, which the Qur'an forbids [3]. Imam Abu Hanifa's own students, Abu Yusuf and Muhammad, also held it impure [5].
Many Hanafi answers today recommend the cautious view in practice. SeekersGuidance calls it the safer position [7], and Darul Ifta Birmingham advises avoiding cheese likely made with such rennet [5].
Pork enzymes and other cheese additives
Rennet or enzymes from pigs are a separate matter. Even the permissive Hanafi view excludes anything derived from swine [7].
Cheese can also contain other animal enzymes. IslamOnline notes that lipase, a flavor enzyme, may come from animal glands, sometimes from pork [4]. It advises avoiding cheese with lipase of unknown source unless the cheese is labeled vegetarian or halal [4].
How to find cheese you're comfortable with
- Look for "microbial enzymes," "microbial rennet" or "vegetable rennet" on the label.
- Look for a halal mark with a named certifier. IFANCA, for example, accepts animal enzymes only from halal-slaughtered animals [8].
- Ask the company about its rennet and lipase sources when the label just says "enzymes" [2].
- Be careful with traditional cheeses that must use animal rennet, such as true Parmigiano Reggiano [4].
Frequently asked questions
Is microbial rennet halal?
Is animal rennet halal?
What does "enzymes" mean on a cheese label?
US cheese standards let makers list rennet and other clotting enzymes of animal, plant or microbial origin simply as "enzymes" [2]. The word alone doesn't tell you the source. Ask the company or look for a halal or vegetarian label.
Is cheese with rennet halal for Hanafis?
Sources
- 21 CFR 184.1685 - Rennet (animal-derived) and chymosin preparation (fermentation-derived) · Legal Information Institute, Cornell Law School · accessed
- 21 CFR 133.113 - Cheddar cheese · Legal Information Institute, Cornell Law School · accessed
- Cheeses made with enzymes taken from animals that are not slaughtered Islamically · Islam Question & Answer · accessed
- Islamic Ruling on Parmesan Cheese · IslamOnline · accessed
- Gelatine and Animal Rennet · IslamQA.org (Darul Ifta Birmingham) · accessed
- The preferred opinion in the Hanafi Mazhab regarding the cheese produced from rennet · Mufti Online (Darul Uloom Zakariyya) · accessed
- Are Protein Supplements Halal? · SeekersGuidance · accessed
- Not as Simple Anymore! · IFANCA · accessed