Avian pepsin
Avian pepsinAvian pepsin is a milk-clotting enzyme used in cheesemaking, an alternative to calf rennet obtained from poultry. It is sold as a clear amber solution, a tan suspension or a light tan powder.
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 | Not listedDoes not appear on this jurisdiction’s permitted list. That is not the same as being prohibited. | ||
| 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
Obtained from the glandular stomachs of chickens. It is an animal-derived enzyme, and anyone avoiding animal ingredients should treat it as one.
- Not vegan
- Not vegetarian
- May raise a halal question
- May raise a kosher question
Compare other additives on the dietary indexes.
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.
Avian Pepsin
Synonyms: None
Assay, identification and purity criteria
Description and assay
- Specification history
- Prepared at the 20th JECFA (1976), published in FNS 1B (1977) and in FNP 52 (1992). An ADI 'not specified' was established at the 20th JECFA (1976)
- SOURCES
- Commercial preparations of Avian Pepsin contain proteolytic enzymes obtained from the forestomach (proventriculum) of chicken or turkey.
- Active principles
- Pepsin (aspartic proteinase)
- Systematic names and numbers Reactions catalyzed
- None (EC 3.4.23.1) The enzyme preparations hydrolyzes polypeptides yielding peptides of lower molecular weight. It clots milk.
- Assay
- Activity not less than 85% and not more than 115% of the declared
- DESCRIPTION
- Clear amber solution, tan suspension, or light tan powder
- FUNCTIONAL USES
- Enzyme preparation Used in clotting of milk in cheese making
- GENERAL SPECIFICATION
- Must conform to the General Specifications for Enzyme Preparations used in Food Processing (See Volume Introduction)
- METHOD OF ASSAY
- Principle Reconstituted milk is coagulated with an avian pepsin solution. The time required to form visible clot is compared with that obtained with a reference standard. Definition of activity The time of clotting T is related to the concentration C of active enzyme by the relation T = t o + kC where k is a proportionality factor which is constant for the same batch of milk, under constant conditions of pH, temperature and calcium ion concentration. Procedure To prepare the substrate solution, disperse 12 g of low-heat non-fat dry milk powder in 94 ml of 0.01 M calcium chloride solution contained in a 100-ml short-neck volumetric flask, stir magnetically 20-30 min then make up to mark with 0.01 M calcium chloride solution. Distribute 10-ml portions in separate test tubes and keep them at 30±0.2 o for at least 10 min, but not more than 1 h. To prepare the enzyme dilutions, introduce into 50-ml or 100-ml volumetric flasks 2 ml and 4 ml respectively of 1.25 M sodium acetate buffer pH 5.7, add distilled water to about two-thirds of the volume of the flask and pipet accurately measured aliquots of the enzyme sample (dissolve, if powdered), and the reference enzyme, dilute to volume. To obtain the desired dilutions (about 1:5,000 strength, arrived at by diluting original sample solution between 25 and 200 fold), distribute 1-ml aliquots of each dilute enzyme solution in test tubes at (18x250 mm) and incubate at 30±0.2 o . To start the reaction pour rapidly the substrate solution contained in one test tube into that containing the dilute enzyme and start concomitantly a stop watch and mix the test solution twice by rapid inversion of the test tube and keep in a slanted position in the water bath kept at 30±0.2 o . Rotate the test tube slowly by hand until the first clots are observed whereupon the watch is stopped and the time is recorded to the nearest 0.1 sec. Calculation Plot the clotting times obtained with enzyme dilutions being assayed and that with the reference standard against the dilution factors employed. Straight lines are obtained for clotting times between 50 and 300 sec. The ratio of the slopes of the lines are inversely proportional to the ratio between the concentrations of enzyme.
Identification
- Pepsin activity
- The sample shows milk clotting activity See description in the Method of Assay
Purity criteria
- Aflatoxin
- Not more than 5 μg/kg Determine as directed in Journal of the AOAC 49, 544 (1966); Pons et al., Determination of Aflatoxins in Agricultural Products: Use of Aqueous Acetone for Extraction.
- Microbiological criteria
- Salmonella spp. Negative Determine as directed in Section 10, Bacteriological Analytical Manual, 2nd. Edition (1969), U.S. Department of Health, Education, and Welfare, or Microbial Limit Tests, U.S.P. XIX, page 588. Pseudomonas aeruginosa Negative Determine as directed under Microbial Limit Tests, U.S.P. XVIII, page 850, or U.S.P. XIX, page 588. Coliforms Not more than 30 per g Determine as directed in Section 41.009, Official Methods of Analysis of the A.O.A.C., 11th Edition (1970), page 841.
- Antibiotic activity
- Negative when examined by suitable methods
Every name it appears under
1 recorded name. A label may use any of them.
Other names
- Avian pepsin
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 Avian pepsin?
- Avian pepsin is a milk-clotting enzyme used in cheesemaking, an alternative to calf rennet obtained from poultry. It is sold as a clear amber solution, a tan suspension or a light tan powder.
- Is Avian pepsin vegan?
- No. Avian pepsin is animal-derived, and is not vegetarian either. This page says what it is made from.
Sources for this page
- jecfaspecs retrieved 2026-09-23
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