Are mycotoxins in coffee a real concern?
- Mar 15
- 3 min read
Updated: Apr 8
What are Mycotoxins?
“Mycotoxins” is a broad term for toxic compounds that can show up in coffee (and other foods). They're produced by certain fungi that can grow on coffee beans and other crops like peanuts, corn, grains, and grapes. Because these fungi thrive in warm, humid conditions, they can grow in the same environments where coffee is often cultivated.
Mold vs Mycotoxins
One common misconception is that mold and mycotoxins are one in the same.
Mold alone DOES NOT automatically equal mycotoxins. Mycotoxins are harmful compounds that some molds can produce under the right conditions. It depends on the type of mold, the moisture level of the coffee, and whether or not the storage conditions allow that mold to thrive.
It is common for un-roasted green coffee to carry mold spores before roasting, where the mold and spores are killed. But if mycotoxins form early enough because of poor storage, those toxins are much harder to get rid of.
Ochrotoxin A (OTA)
The main mycotoxin when it comes to coffee is ochratoxin A. OTA has been linked to several health concerns. It has been classified by U.S. agencies as a possible human carcinogen, and research has also associated it with immune effects and kidney toxicity.
OTA is not something that you can reliably detect by taste or smell, and can be present without any obvious warning signs. It can develop at different points during the handling and storage process, and once it's there, it's not easy to get rid of.
This is why the focus of a coffee brand AND a consumer should be on proper sourcing, proper storage, and testing.
So, What's the Risk of YOUR Coffee?
It's all about how coffee is sourced, stored, and tested. These should be the three things you look for/ask when shopping for coffee.
OTA risk is dependent on how coffee is processed after harvest. In general wet processing is thought to lower the chance of OTA developing because the outer fruit is removed early and the beans are washed and fermented in a more controlled way.
With dry processing, the beans remain inside the whole fruit while they dry, which can create more opportunity for fungal growth if drying or storage conditions are poor. Research also shows that moisture and water activity are major drivers of mold growth and OTA formation, so improper storage after processing can raise risk further.
OTA contamination in coffee can happen at more than one point in the supply chain. Studies suggest it may begin before harvest, but it can also develop during drying, processing, transport, or storage if conditions allow toxigenic fungi to grow. Reviews of the coffee chain emphasize that contamination risk is tied much more to handling, drying speed, moisture control, and storage conditions than to one simple explanation.
What to Look for in a Coffee
Coffee is one of the more regulated crops globally, especially when it comes to international trade. Most commercially sold coffee is screened at some point in the supply chain and falls within established safety limits for contaminants. That said, testing isn’t done on every single batch, and low levels can still be present, just typically below what’s considered harmful based on current standards.
When shopping for coffee, don’t just look for “mold-free” on the label. Look for transparency. Ask if they third-party test for OTA, whether they can share a recent lab report, and how they handle drying, processing, and storage.
Questions to Ask
Do you third-party test for ochratoxin A (OTA)?
Can you share a recent COA or lab report?
Is testing done by batch/lot, or only occasionally?
Do you also test for other mycotoxins, not just OTA?
How is the coffee processed and stored to prevent mold growth?
What moisture-control and storage practices do you use after harvest?
Things to Look for
Third-party testing, not just “clean” or “mold-free” marketing
a COA/lab report with real numbers
batch-specific testing if possible
brands that are transparent about sourcing, drying, processing, and storage
mention of proper moisture control
companies willing to answer direct questions clearly
Things to Avoid
vague claims like “toxin-free” with no proof
brands that only use buzzwords like clean coffee
no lab reports
no mention of batch testing
fear-heavy marketing that makes all regular coffee sound dangerous
Bottom line: OTA is a real contaminant, but that does not mean all coffee is unsafe. Instead of falling for vague “mold-free” claims, look for brands that are transparent about testing, processing, and storage practices
My Favorite Mycotoxin Free Coffee
Purity Coffee - get 20% off
These brands are also very transparent with their testing
Natural Force Clean Coffee
Lifeboost Coffee
Mindful Coffee
Seek Coffee
Fabula Coffee
Kion Coffee
Holistic Roasters
Comments