Ochratoxin A is a mycotoxin: a by-product of mould that can grow on coffee while the green beans are stored and shipped. It is common, usually present in trace amounts, and almost never mentioned. We screen every lot for it, on the green bean, at an ISO 17025 accredited laboratory, before we roast.
The short answer sits at the top because most people arrive at this question a little worried, and the worry deserves a plain reply before the detail.
Where it comes from
Coffee is an agricultural product. It is picked as a fruit, dried, then moved across the world in sacks, often through humid ports and long warehouse stays. Mould finds those conditions hospitable. Two families of mycotoxin can result: ochratoxin A, and the aflatoxins. Neither is exotic. Both are simply what happens when a crop sits in the wrong air for too long.
The amounts are small. That is precisely why they go unremarked. A trace is easy to ignore, and easier still not to look for.
Why most coffee is never tested
Testing costs money and surfaces inconvenient questions. For a commodity sold on price, neither is welcome. So the standard practice across much of the industry is simply not to look. What is not measured cannot trouble the label.
We take the opposite view. If we would not drink it ourselves, it does not leave the roastery.
How we handle it
Every lot is screened before roasting, on the green bean, at an accredited independent laboratory. We test for ochratoxin A and the aflatoxins. The report is filed against the batch, and the result travels with the coffee. This is what we test for, in full.
Roasting, for what it is worth, reduces ochratoxin A further. We test before that step rather than after, because the honest measure is the harder one.
The short answers
Is ochratoxin A dangerous in coffee?
At the trace levels found in most coffee, the risk to a healthy adult is low. The case for testing is not panic. It is the simple preference to know rather than assume.
Does every coffee contain it?
No, but many do, in small amounts. The only way to be sure of a given bag is to test that batch.
Can you taste it?
No. It is invisible to the palate. Which is why testing, not tasting, is the only reliable check.
