I was going to edit the piece I wrote on coffee this morning, but decided that this topic deserved a short post of its own.
Let me start by making one thing very clear: I am not an expert when it comes to coffee. I do however know a lot about nutrition and the human body and have done a fair amount of research on this subject. Also, I drink a lot of coffee, and think you should too!
What are mycotoxins?
Mycotoxins are toxic chemical products produced by fungi that readily colonize crops. They are not unique to coffee beans, but can grow on any type of crop and be found in any type of food or beverage created from contaminated crops. Ochratoxin is the mycotoxin found in coffee beans and has been labeled as a carcinogen and a nephrotoxin (poisonous to kidneys). Basically all you need to know is that they are undesirable and can cause health problems.
How are mycotoxins produced?
When coffee cherries are picked, the pulp is removed in order to leave the green coffee bean to dry. There are different processes for doing this, and they have a huge effect on the growth of mycotoxins.
Wet process: The fruit covering the beans is removed before they are dried. This method requires substantial quantities of water. The skin of the cherry and some of the pulp is removed by pressing the fruit by machine in water through a screen. The bean will still have a significant amount of the pulp clinging to it that needs to be removed, and this is done either by classic fermentation or mechanical scrubbing. The beans must then be dried to a water content of about 10% before they are stable. It is during this drying stage where mycotoxins can begin to grow; if the beans are not sufficiently dried or are dried and then rehumidified during packaging or shipping, mycotoxins will develop.
Dry process: This is the oldest method of processing coffee. Immediately after harvesting, the cherry is cleaned and is set out to dry. This process can take up to 4 weeks, and if the cherries are overdried they will be too brittle and produce broken beans, whereas beans that are not dried enough will be extremely susceptible to the growth of mycotoxins (especially because after drying, the cherries are then typically bulk-stored in silos until hulling, sorting, grading and bagging take place). All the outer layers of the dried cherry are eventually removed in one step by the hulling machine.
The dry method is used for about 90% of the Arabica coffee produced in Brazil, most of the coffees produced in Ethiopia, Haiti and Paraguay, as well as for some Arabicas produced in India and Ecuador. Almost all Robustas are processed by this method. It is not practical in very rainy regions, where the humidity of the atmosphere is too high or where it rains frequently during harvesting. Although the majority of coffee beans are processed by the less expensive dry method, these beans are far more susceptible to mycotoxin growth than those processed using the wet process.
For more detailed information, please refer to the FAO’s Guidelines for the Prevention of Mould Formation in Coffee.
How to choose mycotoxin-free coffee
This is far from an exact science, but from what I can deduce from the research at hand, here is the best strategy:
As I mentioned this morning, you should be buying coffee beans and grinding them yourself. The absolute best method would be to buy green coffee beans (unroasted beans), and then roast them at home. Coffee beans begin to degrade as soon as they are done roasting, and their quality will last no longer than a week; green coffee beans maintain their quality for upwards of 2 years.
Determining the quality of beans is an entirely different ballgame, but the criteria to look for are beans that have the following characteristics:
1. Mechanical Process or Wet Process; preferably machine washed and machine dried.
2. Little to no fermentation.
3. Arabica beans over Robusta beans. Though Robusta varieties do have higher levels of caffeine, they also contain more mycotoxins.
4. Grown at high altitude/elevation. Mold is less likely to grow at higher elevations; the mountains of Central America generally produce excellent coffee beans.
A few other tips:
5. Avoid decaffeinated coffee; Caffeine actually protects coffee beans from the growth of mycotoxins.
6. Stay away from blends. Though blended coffees may taste good, there really is no way of telling where the different bean varieties have come from. Try to stick to single estate products rather than the major brand names.
Is drinking coffee worth the risk?
Yes. Oui. Si. The trick is to find coffee that makes you feel great, rather than coffee that brings you down (if coffee is making you feel terrible, it either contains mycotoxins or you are a slow-metabolizer of coffee, which is a story for another day. Try higher-quality coffee to see if it makes a difference). It will take a bit of research on your part to pick the coffee beans and local coffee shop that are right for you, but the research will be more than worth it when you notice a difference in how you feel.
Am I still going to drink Tim Hortons and Starbucks from time to time? Absolutely I am. I can’t say I really like the taste, nor do I believe the quality of the beans used in these chains is anywhere near where I would like it to be, but mycotoxins or not the benefits of drinking coffee far outweigh living coffee-free. With that being said, when I’m in the comfort of my own home and have control over exactly what I put in my body, I am absolutely going to do whatever I can to ensure that it is of the highest quality- and I suggest you do the same!
Again, I’m not a coffee expert, but I’d be happy to discuss the topic further if you have any questions!