Rennet (animal-derived) and chymosin preparation (fermentation-derived)
9001-98-3 · Rennet (animal-derived) and chymosin preparation (fermentation-derived)CAS 9001-98-3
This listing covers both traditional animal rennet and the fermentation-produced chymosin that has largely replaced it. It is the enzyme that curdles milk into cheese, and the single most consequential dietary question in the whole dairy aisle.
Where it is and isn’t permitted
| Jurisdiction | Status | Scope and limits | Citation |
|---|---|---|---|
| United States | Permitted | 21 CFR 184.1685retrieved 2026-09-07 | |
| Codex Alimentarius | Not listedDoes not appear on this jurisdiction’s permitted list. That is not the same as being prohibited. |
What it is made from
Animal rennet is extracted from the fourth stomach of unweaned calves. Fermentation-produced chymosin is the same enzyme made by yeast or fungi carrying the calf gene, and involves no animal. Both fall under one listing, so the entry alone does not tell you which was used — a cheese labelled with vegetarian rennet uses the fermentation form.
- Vegan status depends on the source
- Vegetarian status depends on the source
- May raise a halal question
- May raise a kosher question
This is not an omission. What this additive is made from is not fixed — depending on the manufacturer it may be plant, animal or microbial in origin, nobody is required to say which, and the same product can change source between production runs. Ask the manufacturer if it matters to you; a label cannot answer it.
- CAS registry number
- 9001-98-3
Every name it appears under
2 recorded names. A label may use any of them.
CAS registry number
- 9001-98-3
As it appears in regulation
- Rennet (animal-derived) and chymosin preparation (fermentation-derived)
Hazard reference values
No reference value for this substance in the sources we hold.
Evidence and how bodies read it
Studies, and the differing conclusions regulators drew from them, are curated by hand rather than machine-read, and none has been written for this substance yet.
Sources for this page
- ecfr retrieved 2026-09-07
Full licence terms and publisher details on Sources. How this page is built and updated: Method.
Machine-readable:/api/v1/additives/rennet-animal-derived-and-chymosin-preparation-fermentation-derived.json