Does FDA require a specific identity method?

No. 21 CFR 111.75 requires at least one appropriate, scientifically valid identity test on every lot of a dietary ingredient and an identity specification per ingredient. FDA warning letters make clear the test must be specific to the ingredient and the reference must be independent of the supplier's lot.

Can DNA testing identify the tissue in an organ supplement?

DNA confirms species in intact tissue but cannot tell liver from kidney, and it does not survive the hydrolysis used to make collagen peptides. Those questions require reading the proteins by LC-MS.

Are you FDA-approved or certified?

FDA does not approve or certify laboratories for this testing. FDA looks for a scientifically valid method, written procedures, authenticated references and complete raw data, which the CoA and data package show.

Does the report prove country of origin?

No. The report identifies species and tissue and whether the lot matches its reference. Geographic origin is a documentation question.

Can you write our identity specification?

Yes. Every report includes specification wording naming the test, the reference and the acceptance criterion, ready for a 21 CFR 111.70(b)(1) specification sheet.

Identity testing for supplement ingredients: species and tissue by LC-MS

For contract manufacturers and brands that handle organ, collagen and protein ingredients.

Every lot of a dietary ingredient needs an identity test before use (21 CFR 111.75(a)(1)), and FDA now rejects tests that other materials would also pass. For proteins, that means a test that reads the proteins themselves. Call it identity testing, ingredient ID testing, source identification or species authentication; the requirement is the same. We run it and give you a Certificate of Analysis with the data behind it.

Which supplement ingredients need LC-MS identity testing

Most identity tests are served well by HPTLC, HPLC, FTIR or DNA at $90 to $300. Four kinds of ingredient are not, because the question is about proteins and the cheaper methods cannot see them.

Organ and glandular powders (bovine or porcine liver, kidney, brain, heart, adrenal, thyroid). The question: is this the declared tissue from the declared species? DNA proves the species but cannot tell liver from kidney. FTIR and NIR fingerprints are not specific enough for a multi-source powder.
Collagen, gelatin and collagen peptides. The question: bovine, porcine, marine or chicken? Hydrolysis destroys DNA. There is no HPTLC fingerprint and no compendial species test.
Protein powders and blends (whey, casein, egg, pea, rice, soy). The question: is the declared source there, and is anything else? Nitrogen counts every protein the same. FTIR misses a partial substitution.
Novel proteins (fermentation, single-cell, insect, algal) for GRAS, AFIC or NDI filings. The question: what is in it, lot to lot, and how much of the named protein? The filing asks for composition and the source organism, which only proteomics gives.

If your ingredient is a botanical, a vitamin, a mineral or an amino acid, keep your current test. We will tell you so if you ask.

Identity tests for organ, collagen and protein ingredients

Each sample is one package: the sample analyzed in replicate alongside blank and quality-control runs, and compared against an independently authenticated reference and the look-alike materials it could be confused with.

Organ identity, species and tissue: confirms the declared species and the declared tissue, with the look-alike species and tissues excluded.
Collagen and gelatin species identity: confirms the declared species, with the look-alike species excluded.
Protein source identity: confirms the declared protein source and screens for sources that are not on the label.

Every package returns a Certificate of Analysis, a retained data package, and identity-specification wording for your spec sheet. Novel-protein composition dossiers for GRAS, AFIC and NDI filings are scoped per project. Quotes within one business day.

Organ supplement identity testing: species and tissue

For desiccated liver, kidney, brain, heart, adrenal, thyroid and other glandular powders from bovine or porcine sources. The report states the species and the tissue, and names the species and tissues that were excluded. It covers species and tissue, not animal age.

Collagen species identity testing

For hydrolyzed collagen, gelatin and collagen peptides declared as bovine, porcine, marine or chicken. Hydrolysis destroys DNA, so species has to be read from the collagen itself. The report names the declared species and the look-alike species excluded.

Protein source identity testing

For whey, casein, egg, pea, rice, soy and blends. The report confirms the declared source and screens for protein sources that are not on the label, which nitrogen tests and FTIR cannot see.

21 CFR 111.75 identity testing: what FDA said in 2026

These are the findings behind most identity-testing citations this year. Each links to the letter on fda.gov.

A supplier's CoA is not an identity test. FDA wrote that 21 CFR 111.75(a)(2) "does not allow firms to rely on a certificate of analysis to confirm the identity of a dietary ingredient." (Mineral BioSciences, June 2026)
A test that other materials would also pass is not specific. FDA rejected an identity specification because other substances met the same criteria, and separately noted that the lab's "reference standard" was the supplier's own lot of the same material. (LXR Biotech, December 2025)
FTIR is not enough for multi-ingredient materials. FDA wrote that FTIR "lacks the specificity to identify the ingredients in multi-ingredient supplement products." (Nature's Elements, April 2026)
Look, smell and taste alone are not an identity test. FDA wrote that organoleptic factors alone "will not provide unique information." (Nutratech, June 2026)

Two more rules reach organ and collagen ingredients specifically. Brain, skull and certain other tissues from cattle 30 months and older are prohibited cattle materials in human food, supplements included (21 CFR 189.5); our report covers species and tissue, not animal age. And a collagen labelled bovine that contains porcine or fish is misbranded, with fish also a major allergen; the 2025 to 2026 collagen recalls were of that kind.

How LC-MS identity testing works

We digest the material and read its proteins by high-resolution liquid chromatography mass spectrometry. Each species, and each tissue within a species, carries proteins the others do not. We compare your lot against an independently authenticated reference for the declared material and against a panel of the look-alikes it could be confused with, and report which were found and which were excluded. The reference is never the supplier's lot of the sample. Each sample is reported against written acceptance criteria.

What is on the Certificate of Analysis

Sample, lot number, declared species and tissue, supplier, date received, chain-of-custody ID
Test name, method and procedure version, acceptance criteria applied
Reference materials used, with their source, stated separately from your own baseline lots
Result: identity confirmed as declared, with the species and tissues excluded, or does not conform
Scope and limits: this is an identity test, not a contaminant, allergen, microbiology or geographic-origin test
Analyst and reviewer sign-off; raw-data retention statement

Behind every CoA we keep a data package: chain of custody, run QC, raw data with checksums, processing records, reference-material records, audit-trail review and sign-off. It is available to you with the CoA or on request, so a records request finds nothing missing.

Identity testing questions we are asked

Does FDA require a specific identity method?
No. The rule requires at least one appropriate, scientifically valid identity test on every lot (21 CFR 111.75(a)(1) and (h)(1)) and an identity specification per ingredient (111.70(b)(1)). FDA's letters make clear the test must be specific to the ingredient and the reference must be independent of the supplier's lot.
Can DNA testing do this?
DNA confirms species in intact tissue. It cannot tell liver from kidney, and it does not survive the hydrolysis used to make collagen peptides. For those questions you need to read the proteins.
Are you FDA-approved or certified?
FDA does not approve or certify laboratories for this testing. What FDA looks for in your records is a scientifically valid method, written procedures that were followed, authenticated references and complete raw data. That is what the CoA and data package show.
Does the report prove country of origin?
No. It identifies species and tissue and whether the lot matches its reference. Geographic origin is a documentation question.
What about contaminants, heavy metals, microbiology?
Not covered by this test. Keep your existing lab for those, or ask us to coordinate.
Can you write our identity specification?
Yes. Every report includes specification wording naming the test, the reference and the acceptance criterion, ready for your spec sheet.

Ready to Confirm Species and Tissue on Every Lot?

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About the laboratory

Dalton Bioanalytics is a mass-spectrometry laboratory at the California NanoSystems Institute, UCLA, 570 Westwood Plaza, Los Angeles, CA 90095, founded in 2019. We run proteomics, metabolomics and lipidomics on Orbitrap instruments for biotech, pharmaceutical and academic customers nationwide, and we apply the same instruments and documentation to ingredient identity for supplement and animal-food manufacturers.

This page describes laboratory testing and is not legal advice. FDA does not approve or certify laboratories. Your quality unit and counsel decide which tests and specifications apply to your products.