Rennet (animal-derived) and chymosin preparation (fermentation-derived)
9001-98-3 · Rennet (animal-derived) and chymosin preparation (fermentation-derived)CAS 9001-98-3
Listed as a thickener, a stabiliser and an enzyme by the US.
Listed as thickeners (US) · stabilisers (US) · enzymes (US) · processing aids (US)
- United States: Stabilizers and thickeners — 21 CFR 184.1685, citing 21 CFR 170.3(o)(28)
- United States: Stabilizers and thickeners — 21 CFR 184.1685, citing 21 CFR 170.3(o)(28)
- United States: Enzymes — 21 CFR 184.1685, citing 21 CFR 170.3(o)(9)
- United States: Processing aids — 21 CFR 184.1685, citing 21 CFR 170.3(o)(24)
Rennet is the enzyme preparation that curdles milk into cheese. This entry covers both traditional animal rennet and the fermentation-produced chymosin that has largely replaced it, so it does not tell you which a given cheese used.
Where it is and isn’t permitted
| Jurisdiction | Status | Scope and limits | Citation |
|---|---|---|---|
| Australia and New Zealand | No listed food uses foundThis site has not matched this substance to any food use on this jurisdiction’s list of authorised food additives. A food additive may be used only in foods that list names. Flavourings, enzymes, processing aids and added nutrients are regulated separately and do not appear on it. | ||
| Canada | No listing matchedHealth Canada’s lists name additives without E or INS numbers, so this site matches them by exact name. A substance listed there under a name this site does not recognise has no row here. | ||
| European Union | No listed food uses foundThis site has not matched this substance to any food use on this jurisdiction’s list of authorised food additives. A food additive may be used only in foods that list names. Flavourings, enzymes, processing aids and added nutrients are regulated separately and do not appear on it. | ||
| Great Britain | No listed food uses foundThis site has not matched this substance to any food use on this jurisdiction’s list of authorised food additives. A food additive may be used only in foods that list names. Flavourings, enzymes, processing aids and added nutrients are regulated separately and do not appear on it. | ||
| Japan | No listing matchedThis site imports only Japan’s list of designated additives (Appended Table 1 to the Regulations for Enforcement of the Food Sanitation Act), matched by English name. Existing additives, natural flavouring agents and ordinary foods used as additives are permitted outside that list and are not imported, so an empty row does not show that Japan does not permit the substance. | ||
| South Korea | No listing matchedThis site imports Part III of South Korea’s Standards and Specifications for Food Additives, matched by CAS number, then INS number, then exact name. Mixed preparations and sanitisers are not imported, and an entry whose identifiers disagreed with a page’s is held for review, so an empty row does not show that South Korea does not permit the substance. | ||
| United States | Permitted | 21 CFR 184.1685retrieved 2026-10-17 | |
| Codex Alimentarius | Not listedDoes not appear on this jurisdiction’s permitted list. That is not the same as being prohibited. |
How much is permitted
A listing usually limits the quantity as well as the food. Only one of the forms that takes is a figure: quantum satis and good manufacturing practice permit the amount the technological effect requires and no more, which is a limit rather than the absence of one. Figures below are the range across every food category this page is listed in, and categories differ between regulators — see how much is permitted.
| United States | — | 1 no quantity stated |
|---|
No regulator sets a figure for Rennet (animal-derived) and chymosin preparation (fermentation-derived). That is not an absence of control: where the listing says quantum satis or good manufacturing practice, the quantity is limited to what the effect requires.
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 yeasts, fungi or bacteria carrying the calf gene, and involves no animal tissue. Cheeses described as made with vegetarian rennet use fermentation-produced chymosin or a microbial coagulant.
- 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.
Compare other additives on the dietary indexes.
- CAS registry number
- 9001-98-3
How JECFA defines it
The international specification for identity and purity, prepared by the Joint FAO/WHO Expert Committee on Food Additives and published by FAO. It is a different document from any above, written by a different body and revised on its own cycle; it is advisory, and a country adopts it or does not.
Chymosin B from Kluyveromyces lactis containing the Prochymosin B Gene
Synonyms: Rennin, milk-clotting enzyme, chymosin, chymosin B, aspartyl protease Aspartyl protease; Chymosin; Chymosin B; Milk-clotting enzyme; Rennin
Assay, identification and purity criteria
Description and assay
- Specification history
- CHYMOSIN B from KLUYVEROMYCES LACTIS containing the PROCHYMOSIN B GENE Prepared at the 53rd JECFA (1999) and published in FNP 52 Add 7 (1999), superseding tentative specifications prepared at the 37th JECFA (1990), published in FNP 52 (1992). ADI "Not specified" established at the 37th JECFA in 1990.
- C.A.S. number
- 9001-98-3
- SOURCES
- Produced extracellularly by the controlled fermentation of Kluyveromyces lactis containing the bovine prochymosin B gene. The fermentation broth is adjusted to pH 2 to convert prochymosin to chymosin, which also kills the production cells. Chymosin is separated from the cell material by filtration and further purified by clarification with diatomaceous earth followed by several cell filtrations and one ultrafiltration.
- Active principles
- Chymosin
- Systematic names and numbers
- None (EC 3.4.23.4)
- Reactions catalyzed
- Cleaves a single bond in kappa-casein
- DESCRIPTION
- Clear, colourless or slightly coloured aqueous solutions containing the active enzyme
- FUNCTIONAL USES
- Enzyme preparation Used in clotting of milk for cheese production
- GENERAL
- Must conform to the General Specifications for Enzyme Preparations used in Food Processing (see Volume Introduction)
Identification
- Milk clotting activity (Vol. 4)
- The sample shows milk clotting activity
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 rather than machine-read, and none has been written for this substance yet.
Common questions
Assembled from what is above, in the words the questions are usually asked in. Each answer is the same statement the relevant section makes, with the same citations behind it.
- What is Rennet (animal-derived) and chymosin preparation (fermentation-derived)?
- Rennet is the enzyme preparation that curdles milk into cheese. This entry covers both traditional animal rennet and the fermentation-produced chymosin that has largely replaced it, so it does not tell you which a given cheese used.
- What is Rennet (animal-derived) and chymosin preparation (fermentation-derived) used for in food?
- It is listed as a thickener, a stabiliser and an enzyme — the role the US assigns it. This page shows every function each regulator records, with the citation for each.
- Is Rennet (animal-derived) and chymosin preparation (fermentation-derived) banned in Europe?
- No. Rennet (animal-derived) and chymosin preparation (fermentation-derived) does not appear on the EU's list of authorised food additives, which is not the same as being banned: the EU permits an additive only where it has authorised it, and usually the reason for an absence is that no one applied. The EU has made no finding against this substance. It does mean it may not be used as a food additive in the EU today.
- Where is Rennet (animal-derived) and chymosin preparation (fermentation-derived) permitted?
- Of the seven regulators this site reads, the US permits it. Each permission is for named foods at named levels, not a blanket one; the table on this page gives them with citations.
- Is Rennet (animal-derived) and chymosin preparation (fermentation-derived) vegan?
- It depends on the source, and a label will not tell you. Rennet (animal-derived) and chymosin preparation (fermentation-derived) can be made from plant or animal material, manufacturers are not obliged to say which, and the same product can change between production runs. Anyone who needs to know has to ask the manufacturer.
Sources for this page
- ecfr retrieved 2026-10-17
- jecfaspecs retrieved 2026-09-23
Full licence terms and publisher details on Sources. How this page is built and updated: Method.
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