Every serious brand in this category tells you to ask for a certificate of analysis. Almost none of them tell you what to do with it once you're holding one. So people open a PDF, see a laboratory letterhead and a table of numbers, decide it looks official, and buy. That reaction is the reason a weak COA works as well as a strong one.
A real certificate of analysis names three things: the sample it tested (a batch or lot number), the method used, and a measured number with its units. If any of the three is missing, it isn't a COA — it's a document that resembles one. The two most common substitutes are a certificate of conformity, which approves a product type for a validity period rather than testing your batch, and a marketing summary that reports "pass" without a value. Check the batch number against the container in front of you first; that single comparison eliminates most of what's circulating.
Below is how to work through one in about five minutes, using the documents we publish on our own lab certificates page as the worked example — including the parts of them that don't tell you everything you might want.
What Is a Certificate of Analysis, Exactly?
It's a laboratory report on one specific sample. Not on a brand, not on a species, not on a product line — on the material that was physically sent to the lab, on the date printed at the top. That narrowness is the whole point. A COA is evidence about a defined quantity of powder or dried fruiting body, and its usefulness to you depends entirely on how tightly that quantity connects to the jar you're about to open.
Three elements make a report interpretable. The sample identifier ties it to a production run. The method tells you whether the number can be trusted for that matrix. The result gives a value with units and a basis. Strip any one out and the document becomes decorative.
Why Isn't a Certificate of Conformity the Same Thing?
Because it approves a category, not a measurement. Our own conformity certificate, reference TER.1.X.020-25, covers "dried mushrooms and mushroom products made from them" and runs from 10 March 2025 to 9 March 2026, with an appendix listing the 16 products included. That's a regulatory approval with an expiry date. It says our assortment is permitted to be sold as what it claims to be. It contains no test values at all.
The test protocols sitting beside it on the same page are the analytical documents: protocol No. 0182 for microbial indicators and protocol No. 0182(1) for toxic elements. Those have numbers. The conflation of these two document types is the single most common piece of theatre in supplement marketing, because a conformity certificate looks more official and covers more products for longer.
| Certificate of conformity | Test protocol (COA) | |
|---|---|---|
| What it describes | A product type or assortment | One physical sample |
| Contains measured values | No | Yes |
| Has a validity window | Yes, typically a year | No — it describes that sample forever |
| Tells you about your jar | Only that the type is approved | Only if the batch matches |
Notice the asymmetry in the last row. A conformity certificate that's still inside its validity window genuinely applies to your purchase, but it tells you almost nothing. A test protocol tells you a great deal, but only about its own sample. Neither one alone is what most buyers think they're getting.
Does the Batch Number Match the Product in Your Hand?
This is the check that does the most work, and it's the one people skip. Find the lot or batch code on the container, then find the sample identifier on the report. If they don't match, you're reading about different material. Plenty of brands publish one COA from 2021 and keep it up permanently while their supplier changes twice.
Being straight about our own documents: the microbiology protocol was run on a Phallus impudicus sample under batch 0291, and the toxic elements protocol was run as a mixed sample under batch 0292 across the dried assortment. A mixed sample characterises the assortment. It does not characterise your individual jar the way a per-lot test would, and anyone telling you otherwise about their own mixed-sample report is overselling it.
What Does "Not Detected" Actually Mean?
It means the instrument couldn't see it. That's a statement about the method, not about the product, and the difference matters enormously. Every analytical method has a limit of detection and a limit of quantification — the concentrations below which it can't confirm presence, and below which it can't put a reliable number on it. "ND" without a stated limit is an unfinished sentence.
So read the limits column, not just the results column. A report that quantifies a small amount is doing its job. A report that says nothing was found, using a method it doesn't name, at a limit it doesn't state, is asking you to trust an absence. Our own toxic elements protocol covers mercury, cadmium and lead, plus caesium-137 and strontium-90 radionuclides — a panel shaped by the origin of the material, since wild mushrooms are efficient concentrators of caesium and Eastern European harvest sites make that worth measuring.
The broader point about which metal deserves your attention, and why the legal limit printed beside a result is usually the wrong comparison, is worked through in detail in our guide to heavy metals in mushroom supplements.
Which Tests Belong on the Panel?
Four families, and most published COAs cover one or two. Knowing which are missing is more informative than reading the ones that are present, because the absent test is the one nobody wanted the result of.
| Family | What it answers | What to look for |
|---|---|---|
| Identity | Is this the species on the label? | DNA (ITS) barcoding, or microscopy on unprocessed material |
| Potency | How much of the active fraction is there? | Beta-glucan by enzymatic assay, with units and basis |
| Contaminants | What came along with it? | Cadmium, lead, arsenic, mercury; pesticides; residual solvents for extracts |
| Microbiology | Is it safe to swallow? | Total aerobic count, moulds and yeasts, salmonella, coliforms, S. aureus |
Identity is the family most often absent and the hardest to fake. Once material has been milled, dried or extracted, the visual features that identify a species are gone, which is exactly the problem Raja and colleagues addressed in 2016 by generating ITS barcodes from 33 samples including grocery mushrooms, powdered mycelium and commercial capsules (Food Chem, 2017). The technique works on processed material. Its near-total absence from published COAs isn't a technical limit.
Who Ran the Test, and Are They Accredited For It?
Look for a named laboratory with an accreditation reference, and then check what that accreditation covers. ISO/IEC 17025 accreditation isn't a blanket badge — it's granted for a defined scope of methods and matrices. A lab accredited for microbiological testing of foodstuffs is not thereby accredited for elemental analysis, and a scope document will say so explicitly.
Our protocols came from the testing laboratory of the Ternopil branch of the state standardization and certification centre, and the certificate names it in full. An in-house result from the brand's own quality department isn't worthless, but it isn't independent either, and a report with no laboratory name on it shouldn't count for anything.
How Do You Read the Potency Line Without Being Fooled?
Start with the analyte name, because that's where the substitution happens. "Polysaccharides" is not beta-glucan — it's a broader bucket that includes the starch carried over from grain substrate, which is why a mycelium-on-grain product can report an impressive polysaccharide figure honestly. The validated approach separates the 1,3:1,6 beta-glucan of fungal cell walls from cereal 1,3:1,4 glucan and from starch (McCleary & Draga, J AOAC Int, 2016).
Then check three things about the number itself. Units: mg/g and percent differ by a factor of ten, and both appear. Basis: as-received or dry weight, since a 10% moisture difference moves the result. Reference quantity: per 100 g of powder is not per serving, and a COA reporting the former next to a label claiming the latter is comparing nothing. The full walkthrough of that distinction lives in beta-glucan versus polysaccharide on labels.
How Old Is Too Old for a COA?
There's no rule, so use the material's own logic. A contaminant result reflects one harvest from one place; the next harvest is a new question, which makes a three-year-old metals report weak evidence about today's stock regardless of how good the number was. A potency result is more stable, since extraction processes change less often than growing conditions.
Our own document set is dated 10 March 2025 and we say so on the page rather than hiding it, which is the standard to hold anyone to: a visible date you can judge for yourself. A COA with no date is not a document, it's a graphic.
What Should Make You Walk Away?
- No batch or lot identifier anywhere on the report
- Results given as "pass", "complies" or "conforms" with no measured values
- "Not detected" with no limit of detection or quantification stated
- No laboratory name, or a logo without an accreditation reference
- No date, or a date the brand won't connect to current stock
- A conformity certificate offered when you asked for test results
- "Polysaccharides" presented as the beta-glucan figure
- An emailed screenshot rather than the full original document
A Five-Minute COA Audit
- Confirm it's a test protocol with numbers, not a conformity certificate.
- Match the batch identifier against the container in front of you.
- Read the date, and ask whether the current stock is from the same harvest.
- Check the laboratory name and its accreditation scope for the tests reported.
- For every "not detected", find the stated limit; if there isn't one, discount the line.
- On potency, verify the analyte is beta-glucan, then check units, basis and reference quantity.
- List which of the four test families are absent, and ask the brand why.
Most of the value comes from steps one and two. If you only ever do those, you'll still be reading these documents better than the great majority of buyers — and better than some of the brands publishing them.
Frequently Asked Questions
What is a certificate of analysis for a mushroom supplement?
A laboratory report on one specific sample of material, naming the batch tested, the method used, and the measured results with units. It's evidence about that sample only, which is why matching its batch identifier to your own container is the first thing to check.
Is a certificate of conformity the same as a COA?
No. A conformity certificate approves a product type for a validity period — ours runs 10 March 2025 to 9 March 2026 across 16 products — and contains no test values. A COA reports measured numbers for a single sample and has no expiry, because it only ever described that sample.
Is "not detected" on heavy metals a good sign?
Not on its own, and for mushrooms it's often a warning. Clean dried mushroom material typically carries 1–5 mg/kg cadmium in dry matter, which competent instruments detect easily. A stated number with a stated limit of quantification is stronger evidence than an unqualified "ND".
How recent should a certificate of analysis be?
Recent enough to cover the harvest your product came from. Contaminant results reflect one growing site and season, so a report several years old says little about current stock. Potency results age better, since extraction methods change less often than growing conditions.
Can I ask a brand for a COA directly?
Yes, and the response is itself informative. A brand that sends the full original document, dated and batch-identified, is behaving normally. One that sends a cropped screenshot, a conformity certificate or a summary saying "all tests passed" has answered a different question than the one you asked.
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Our test protocols and conformity certificate are published in full on the lab certificates page, with the original PDFs rather than summaries — including the mixed-sample caveat described above. They cover the dried range, including chaga chunks and dried reishi, alongside capsule products such as lion's mane capsules and reishi capsules. Browse the dried mushrooms collection or the capsule range. Free shipping over €50.
Related Articles
- How to Read a Mushroom Supplement Label
- Beta-Glucan vs Polysaccharide on Labels
- Heavy Metals in Mushroom Supplements
- How to Read a Lion's Mane Label
- How to Read a Reishi Label
- Lion's Mane: Fruiting Body vs Mycelium
- How to Check Amanita Muscaria Quality
Sources
- McCleary BV, Draga A. Measurement of β-glucan in mushrooms and mycelial products. J AOAC Int. 2016;99(2):364-373. PubMed 26957216
- Raja HA, Baker TR, Little JG, Oberlies NH. DNA barcoding for identification of consumer-relevant mushrooms: a partial solution for product certification? Food Chem. 2017;214:383-392. PubMed 27507489
- Kalač P. Trace element contents in European species of wild growing edible mushrooms: a review for the period 2000-2009. Food Chem. 2010;122(1):2-15. doi:10.1016/j.foodchem.2010.02.045
- ISO/IEC 17025:2017. General requirements for the competence of testing and calibration laboratories. iso.org
- Eurachem. The Fitness for Purpose of Analytical Methods — a laboratory guide to method validation and related topics. 2nd ed. 2014. eurachem.org
- Commission Regulation (EU) 2023/915 on maximum levels for certain contaminants in food. eur-lex.europa.eu