When a customer asks “is this product safe?”, the honest answer isn’t on the label. It’s in the QC release file. Here are the 12 tests we run on every batch before it ever leaves Srebrenik, and what each one rules out.
Why 12, not 4
The legal minimum (EU and U.S.) is roughly four tests: identity, microbiological, heavy metals, and disintegration for solid dose forms. Those will get you through an audit. They will not catch every problem. Here’s what 12 looks like.
The 12 tests
1. Identity (HPLC or FTIR)
Confirms the raw material is what the supplier says it is. We’ve caught labelled “Curcuma Longa 95%” that came in at 78%. Cheap to test, expensive to skip.
2. Active assay (potency)
Quantifies the actual mg of the active in the finished form. Label claim says “Vitamin D3 5,000 IU”? The assay shows what’s really there. Acceptance: typically ±10% of label claim.
3. Disintegration (solid dose forms)
Capsule or tablet must break down within 30 minutes in simulated gastric fluid. If it doesn’t, the active never reaches the bloodstream, you’re selling a swallowing exercise.
4. Dissolution
One step beyond disintegration: how much of the active dissolves into solution within a target time window. Required for any controlled-release formulation and good practice for everything else.
5. Weight uniformity
Sample 20 units, weigh each. Variance must stay within USP limits. Catches dosing errors before they become customer complaints.
6. Microbiological, total aerobic count
How many viable bacteria per gram. Limit varies by product type. Failure usually points to humidity or hygiene issues.
7. Microbiological, yeast and mould
Separately quantified. Yeast/mould failures typically point to raw material contamination (especially herbal extracts) or packaging integrity issues.
8. Microbiological, pathogens (E. coli, Salmonella, S. aureus)
Zero tolerance. A single positive = batch rejected, recall procedure activated, root cause investigation.
9. Heavy metals, lead
EU limit: variable by product type. We hold every batch to 5× stricter than the EU max. Lead is the contaminant most likely to fail Prop 65 in California.
10. Heavy metals, cadmium, mercury, arsenic
Same 5× stricter standard. Arsenic in particular is a common contaminant in seaweed, fish oil, and certain Asian-sourced botanicals.
11. Moisture content (Karl Fischer or oven loss)
Out-of-spec moisture in powders or capsules accelerates degradation, encourages microbial growth, and ruins shelf life. We measure on every batch.
12. Visual / appearance
Sounds basic, is critical. Color, shape, surface defects, foreign particles, label print quality. Last line of defence before shipping.
What “passing” actually looks like
Every batch generates a Certificate of Analysis listing all 12 tests with measured values vs specification. We file the CoA, you receive a copy with the shipment, and you can share it with retailers, regulators, and curious customers.
What we do when a test fails
Internal release testing failure = batch quarantined, never leaves the facility. We re-manufacture at our cost. If a third-party lab finds a deviation post-shipment, we cover replacement and analytical re-testing. This is in your contract.
Where third-party testing fits
For markets that require it (especially the U.S. and Germany), we send samples to independent EU and U.S. accredited labs for confirmatory testing. We maintain relationships with three labs and pick the closest accredited lab to your target market.