What is poison coffee?

In this text we will answer the query, “What is poison coffee?” We will also discuss other questions like what should you do if you get food poisoning and how does contamination occur in coffee. 

What is poison coffee?

Poison coffee is coffee that has been contaminated by fungi that have produced mycotoxins. It is quite unlikely since roasted coffee does not have favorable conditions for the growth of bacteria and fungi. However, green coffee already presents a very favorable environment for the growth of fungi. 

Thus, coffees may be contaminated with fungal products of mycotoxins. Which are resistant to the roasting process.

For example, ochratoxins are produced by strains of Aspergillus spp. and Penicillium spp. These mycotoxins are usually present in cereals, coffee and bread, described in 1965 as a secondary compound of Aspergillus ochraceus.

Ochratoxigenic fungi are one of those that can contaminate coffee beans. Producers of ochratoxin A occur mainly due to long periods in which the coffee stays in bags after harvesting until drying, periods of rain during the drying stage in terraces, lack of turning over the beans and inadequate storage. 

The International Agency for Research on Cancer (IARC) has classified ochratoxin A in Group 2B, which considers it potentially carcinogenic in humans.

How much ochratoxin A in coffee is safe?

The European Commission has not yet set maximum levels for ochratoxin A (OTA) in coffee and only has a recommendation, whereby the reference level of 3ppb for roasted and ground coffee and 8 ppb for green coffee was suggested for the member countries of the European Community. 

Currently, the only European Union countries to apply legal limits for OTA are Italy (8ppb for processed coffee and 4ppb for the final product), Finland (10ppb) and Greece (20ppb). Czech Republic – 20 µn/Kg, Romania – 5 µg/Kg.

In Brazil, ANVISA establishes the maximum limit of ochratoxin A in roasted coffee (ground and beans) and in soluble coffee at a concentration of 10 µg/kg.

How does the contamination occur in coffee?

The hole caused by the drill in the coffee bean can facilitate the entry of bacteria and fungi inside the fruit. The greenish color presented by the grains occurs due to the mechanical action of perforation and oxidation, as well as the presence of fungi and bacteria. 

In addition, the presence of the pest added to processing failures along the chain, especially during the post-harvest stages, can lead to the development of toxin-producing fungi, the so-called toxigenic fungi. 

In addition to altering the quality of the coffee, these microorganisms can jeopardize the safety of the product, as they produce secondary metabolites that, even in small concentrations, are harmful to humans and animals.

It is very rare to get food poisoning from coffee, as it is not conducive to bacterial growth. One risk is the presence of mycotoxins. However, their presence in coffee is rare. Furthermore, the contamination that results in the production of mycotoxin in coffee results in strong odors and is easy to identify.

Will old coffee make you sick?

No, the simple fact that coffee is stale is not harmful to your health. However, if this coffee is contaminated and has the production of toxins (ochratoxin – OTA), it can have serious effects on human and animal health.

Thus, drinking coffee beans or ground coffee will not, in the vast majority of cases, put you in any kind of danger of getting sick. Coffee made from stale coffee, on the other hand, will not taste as good as those made from fresh coffee and may even taste stale or unpleasant. There are, however, some notable exceptions to this general rule.

Coffee that has not been stored properly in an airtight container can develop a bitter taste under certain circumstances. When coffee beans or grounds are not properly packaged, exposed to water, or have mold or other lumps, there is a high chance that they can make you sick, even when the coffee is brewed with boiling water.

How can I avoid consuming OTA-infected coffee beans?

The most efficient way to prevent OTA contamination in your coffee is to be aware of where your beans come from. Note the farm where they were grown, the processing facility where they were processed and the means of transport that was used to transfer them.

Keep your insistence on only buying coffee beans from companies that do OTA testing. That’s all there is to it.

What is the expiration date of the coffee?

The faster the better: Even with astronomical expiration data indicating that the coffee is good for consumption several months after opening. The ideal time to consume coffee is between 30 and 90 days. From that time onwards, a drop in quality is vertiginous, and the grain loses its flavor.


In this text we have addressed the query, “What is poison coffee?”. We also discussed other questions like what should you do if you get food poisoning and how does contamination occur in coffee.



Hi, I am Charlotte, I love cooking and in my previous life, I was a chef. I bring some of my experience to the recipes on this hub and answer your food questions.