Mold and Mycotoxins in Coffee: What the Research Actually Shows

In some cases, coffee can have trace mycotoxins, mostly ochratoxin A. There are food-safety controls in place to limit consumer exposure to them. Although roasting can reduce the amount of mycotoxins in coffee, it doesn’t eliminate all of them.

In this MDLA article, you will also learn about mold in coffee, is coffee a toxin by itself and how to ensure you are having a safe cup.

Sourcing transparency note: Regulatory figures below come from current EU legislation. Scientific claims rely primarily on peer-reviewed research and authoritative food-safety sources. MDLA testing claims refer to published Eurofins results.

What Are Mycotoxins, Really?

So let’s answer the question that bothers many, “What are mycotoxins in coffee, and should I be concerned about them?” In a nutshell, those are toxic chemical compounds that some types of mold produce. In coffee, the best-studied mycotoxin is ochratoxin A (a.k.a. OTA). Some studies also find aflatoxin B1 and other aflatoxins, but OTA is the most prominent one.

So, mold is the main culprit in this situation. It is also a living organism, and high roasting temperatures can destroy it (specifically, fungal spores and mycelium). However, mycotoxins are relatively heat-stable, so when produced, they may withstand even high roasting temperatures. 

Current EU safety limits under Regulation (EU) 2023/915 set a maximum OTA level of 3 μg/kg for roasted coffee beans and ground roasted coffee and 5 μg/kg for soluble coffee. 

Mycotoxin Symptoms

The main challenge of discussing the symptoms of mycotoxins in coffee is that there are other places you can get exposed to them, both environmentally and dietarily. For instance, being exposed to mycotoxins in damp or moldy environments can lead to respiratory and allergic symptoms. 

That is, however, different from exposure to drinking coffee. For dietary mycotoxins, the potential effect depends on the toxin, its dose, and the duration of exposure. WHO and EFSA recognize OTA and mycotoxins as genuine food-safety concerns. At high enough exposure from food, they can damage the kidneys (especially with OTA) and liver, cause vomiting, headache and abdominal pain.

That is exactly why there are regulations and monitoring in effect for mycotoxins in coffee beans, as well as other foods.

Does Roasting Really Remove Mycotoxins?

So, does roasting reduce mycotoxins in coffee? Yes, particularly OTA, but there is no reliable universal percentage. A 2024 review reported OTA reductions of roughly 12% to 90%, depending on roasting temperature and initial contamination. Other studies have produced similarly wide ranges.

The key effect of roasting on mycotoxins in coffee is therefore reduction rather than guaranteed elimination. More intense roasting can substantially decrease OTA under some conditions, but prevention during drying and storage remains important.

Arabica vs Robusta vs Organic

While there is some research into mycotoxins in Arabica vs Robusta coffee, it isn’t comprehensive. One study detected OTA in 36.6% of Robusta compared with 21.6% of Arabica samples, but post-harvest handling matters too.

Dry processing is associated with higher OTA contamination than wet processing. Robusta is also more commonly dry-processed in certain producing regions. However, origin, climate, drying practices, storage, and handling can all influence mold growth and mycotoxin formation.

A separate note for those researching mycotoxins in coffee Arabica vs Robusta vs organic. Organic is not a separate type; it only refers to the way of growing and handling the coffee plants. To learn more about mold and mycotoxins in organic coffee, see the next section.

MDLA sources 100% Arabica beans for every capsule. Explore our enriched Brew Caps - crafted with quality-focused sourcing practices from bean to capsule.

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Does Organic Coffee Have Less Mold?

Does organic coffee have mold? It can. EU organic certification restricts artificial fertilizers and pesticides and sets rules for production, but it is not itself a laboratory test for mold or mycotoxins.

Proper drying and dry storage have a more direct role in preventing fungal growth. Specialty-grade sorting can add physical defect screening, including the removal of damaged beans. Organic certification and contaminant testing should therefore be viewed as separate quality systems.

So, what coffee does not have mold? As of now, there is no coffee category that can honestly guarantee zero mold or zero mycotoxins. Independent testing and the provider’s ingredients & quality standards can provide more specific information about a tested product or batch.

Coffee Capsules and Mold Risk: Does Format Matter?

Sealed capsules reduce coffee's exposure to ambient moisture and oxygen after packaging compared with repeatedly opening and resealing a bag of ground coffee. Keeping coffee dry limits opportunities for new mold growth and also helps preserve freshness.

However, capsules are not automatically mold-free. Packaging also cannot remove an OTA or another mycotoxin that was already present before sealing. See our coffee beans vs capsules guide for a broader comparison.

How to Minimize Mold and Mycotoxin Exposure From Coffee

• Buy coffee from producers with transparent quality controls.

• Keep beans and grounds dry and properly stored.

• Avoid visibly moisture-damaged or moldy coffee.

• Follow the manufacturer's storage instructions.

• Treat organic and specialty-grade labels as quality characteristics, not guarantees of zero mycotoxins.

• Look for independent contaminant testing when possible.

Quality should not simply be taken on trust. MDLA Organic Mushroom Coffee is independently tested by Eurofins for mycotoxins, including OTA and aflatoxins, alongside heavy metals and microbiological parameters. The published report recorded OTA below 0.5 μg/kg, and each tested aflatoxin below 1 μg/kg in the analyzed sample.

Explore our testing approach on the Product Quality page or learn more about ingredients in our Wellness Dictionary.

Quality shouldn't simply be taken on trust. MDLA Organic Mushroom Coffee is independently tested by Eurofins for mycotoxins, heavy metals and microbiological parameters. Explore how we approach product quality and testing.

FAQ

Does all coffee have mold?

No. The question, “Does all coffee have mold?” confuses living mold with residual mycotoxins. Properly processed and stored coffee does not necessarily contain viable mold.

Is there mold in my coffee if it's specialty grade?

Not necessarily. If you are asking if there is mold in coffee, specialty-grade screening can reduce physical defects, but grading is not laboratory proof that mycotoxins are absent.

Do mycotoxins in coffee actually cause symptoms?

Mycotoxins can cause adverse health effects at sufficiently high exposure, but symptoms after drinking coffee cannot automatically be attributed to mycotoxins. This is why regulatory limits and contaminant controls are important.

Does organic coffee have less mold than regular coffee?

Organic certification does not guarantee lower mold or mycotoxin levels. Drying, handling, and storage remain important.

Which has more mycotoxins: Arabica or Robusta coffee?

According to some studies, Robusta, but it also depends on processing, origin and storage.

Does decaf coffee have more mold than regular coffee?

There is no evidence for this claim. For decaf coffee, processing, origin and storage matter as much as for regular coffee.

Are coffee capsules or pods lower-risk for mold than ground coffee?

Sealed capsules and pods limit exposure to ambient moisture after packaging, but they cannot remove pre-existing mycotoxins. Format alone does not guarantee safety.

Sources

1. https://doi.org/10.1080/19440049.2017.1393109

2. https://www.cdc.gov/niosh/mold/health-problems/index.html

3. https://eur-lex.europa.eu/eli/reg/2023/915/oj

4. https://www.efsa.europa.eu/en/news/ochratoxin-food-public-health-risks-assessed

5. https://doi.org/10.3390/jof10080590

6. https://www.who.int/news-room/fact-sheets/detail/mycotoxins