What a saffron extract is tested for before it reaches you
A properly specified plant extract arrives with a specification sheet, and that sheet names every contaminant the material has been tested for and the limit it has to sit under. For a saffron extract that list runs to four heavy metals, four aflatoxins, plant alkaloids, polycyclic aromatic hydrocarbons, melamine, pesticide residues and seven separate microbiological limits.
If you have ever wondered whether anyone actually checks, this is the document that answers it. And if a brand cannot produce one for the ingredients it uses, that is also an answer.
Heavy metals
Lead, arsenic, cadmium and mercury are measured by inductively coupled plasma mass spectrometry, which detects them at very low concentrations, and the limits are set by European contaminant regulation (EC 915/2023).
On one saffron extract specification the limits are lead under 0.5 parts per million, arsenic under 1.0 ppm, cadmium under 0.5 ppm and mercury under 0.1 ppm.
The interesting detail on that sheet is a footnote. The lead and cadmium limits are marked as agreed at a customer's request, meaning they are set tighter than the regulation itself requires because a buyer asked for tighter ones. That is worth knowing, because it means these limits are negotiable upward by whoever is purchasing. A manufacturer who cares can ask for better than the legal minimum, and some do.
Moulds, plant toxins and combustion residues
Aflatoxins are produced by moulds that grow on crops in storage, and they are among the most tightly regulated contaminants in food. The specification sets aflatoxin B1 under 5 parts per billion and the sum of B1, B2, G1 and G2 under 10 ppb, measured by liquid chromatography with tandem mass spectrometry.
Pyrrolizidine alkaloids are the ones most people have never heard of and probably should have. They come from weeds that grow among a crop and get harvested along with it, they are a genuine issue in botanical ingredients generally, and here they are capped under 400 ppb.
Polycyclic aromatic hydrocarbons come from drying with combustion gases. Benzo(a)pyrene is capped under 10 ppb and the sum of four of them under 50 ppb. Melamine, an adulterant with a notorious history in powdered ingredients, is capped under 2.5 ppm.
Microbiology
Seven limits, set against European food safety regulation (EC 2073/2005) and the European Pharmacopoeia.
- Total aerobic microbial count under 10,000 colony forming units per gram
- Yeasts and moulds under 100 CFU per gram
- Bile-tolerant Gram-negative bacteria under 100 CFU per gram
- E. coli absent in 1 gram
- Staphylococcus aureus absent in 1 gram
- Salmonella absent in 25 grams
- Listeria monocytogenes absent in 25 grams
Absent in 25 grams is a stricter test than absent in 1 gram, and it is applied to the two organisms where the consequences of getting it wrong are worst.
The distinction most people miss
Tested is a word that covers two quite different things, and a specification sheet will tell you which is which if you read the control plan at the bottom.
Some assays run on every single production batch. On a saffron extract these are typically identity, the standardisation marker, the chromatographic fingerprint, bulk density, ash, loss on drying, particle size and the routine microbial counts.
Others run periodically, often annually, on the ingredient or on the incoming raw material rather than on each finished batch. Contaminant panels and pesticide residues, the latter run to EC 396/2005, usually sit in this group, for the practical reason that they are testing an agricultural input which does not change batch to batch in the way a manufacturing step can.
Both are normal and both are legitimate. The point is that they are not the same claim, and knowing which is which is most of what reading a specification is for.
Specification, or certificate of analysis
These two documents get confused constantly and they do different jobs.
A specification is the promise. It says what every batch of this ingredient will meet. It carries limits, not results, and it has a revision number rather than a batch number.
A certificate of analysis is the proof. It is a specific batch, identified by batch number, with the measured figures from that batch printed against those limits.
If you want to know whether an ingredient meets a standard, ask for the specification. If you want to know whether the material in your hand met it, ask for the certificate of analysis for that batch. The second question is the harder one, and it is the one worth asking.
What to take from it
Contaminant testing on botanical ingredients is not exotic or optional. It is documented, regulated, and it is written down on a sheet that a manufacturer can hand over.
The question is never whether testing exists. It is whether the company selling to you can show you the paperwork.
Studies conducted on individual ingredients, not on any finished product. Individual results may vary.