How do I read a pharmaceutical gelatin specification (COA)?

Beyond Biopharma | Pharmaceutical Gelatin FAQ

Short answer: Read a pharmaceutical gelatin certificate of analysis in layers. Confirm the product identity and batch number first, then review the functional results such as Bloom and viscosity, then the purity and microbiological results, and finally the source, storage and compliance statements. Compare every numeric result or 'conforms' statement with the specification you agreed with the supplier, and treat any result outside the agreed range as a reason to quarantine the batch until the difference is explained.

Start with identity and batch information

The top of a certificate identifies what was tested: the product name and grade, the supplier, the batch or lot number, the quantity, the date of manufacture, the date of analysis and the expiry or retest date. Also look for the reference standard or monograph the certificate is written against, such as USP-NF, EP or JP, because the same batch can carry different results depending on the method used. If any of these fields does not match your purchase order or the label on the container, stop and ask the supplier before you accept the material.

Functional and physical properties

• Bloom (gel strength) - the value that most strongly controls behaviour in capsule or dosage-form use; compare it with your agreed range.
• Viscosity - check the conditions, typically a defined concentration such as 6.67 % w/w at 60 degrees C, because viscosity only means something together with its test conditions.
• Moisture or loss on drying - interacts with storage, brittleness and microbiological stability.
• pH and particle size - confirm they match your process expectations, including the sieve or mesh profile where relevant.
• Appearance and clarity - a visual or solution-clarity check for colour, odour and dissolved clarity.

Purity results

The purity section reports residues that are controlled by the pharmacopoeia or by your own specification: sulphur dioxide (SO2), heavy metals, arsenic, chromium where the monograph requires it, ash or sulphated ash, and identification-related tests such as nitrogen or protein content. Values may be shown as numbers with limits, or as a 'conforms' statement where the monograph defines the pass level. Confirm that the methods cited are the current official ones and that the edition or revision date is stated.

Microbiology and, where relevant, endotoxin

Check the microbiological results: total aerobic microbial count, total combined yeast and mould count, and absence of the specified organisms named in the applicable monograph. For grades that need it, an endotoxin result may appear with its method and limit; for ordinary capsule or tablet grades this line is normally absent. Distinguish the two: microbial count is about bioburden, while endotoxin is a separate, context-dependent test.

The statements at the foot of the certificate

Read the closing declarations carefully because they carry as much weight as numbers: the gelatin type (Type A or Type B), the animal source and species, the BSE/TSE statement for bovine material, halal or kosher certification where applicable, GMP status, and any statement of compliance with a specific pharmacopoeia edition. Cross-check these statements against the documentation you requested, and keep the COA with the batch records so the link between the certificate and the physical lot stays traceable.

Common mistakes when reading a COA

• Confusing typical values with limits - a brochure may quote a typical Bloom while the COA shows a specification range; work from the agreed range.
• Mixing pharmacopoeias - a result obtained by one monograph method is not automatically the result under another.
• Ignoring method and edition - old certificates or undated methods may not reflect the current edition you must meet.
• Trusting marketing text - the certificate, not the sales sheet, is the document that matters for release.

Related reading

See also what purity tests matter for pharmaceutical gelatin, what microbial limits apply and how pharmacopoeia compliance is tested.