Is there really any danger of mycotoxins in chocolate?

Dave Asprey has repeatedly warned about the risk of mold contamination in chocolate and, for this reason, has suggested European chocolates, which are governed by stricter standards.

In an article on this issue (, he wrote this:

According to the International Journal of Food Microbiology Vol. 125 (2008) the aspergillus flavus fungi that infects cocoa makes more toxins that just aflatoxin:

The present study reports on the natural mycobiota occurring in cocoa beans, paying special attention to the incidence of fungal species that are potential producers of mycotoxins. The results show that predominant fungi were different species of the genus Aspergillus belonging to section Flavi and Nigri. … Potential ability to produce aflatoxins (AFs) B1, B2, G1 and G2, cyclopiazonic acid (CPA)and ochratoxin A (OTA) was studied by isolate culture followed by HPLC analysis of these mycotoxins in the culture extracts. Results indicated that 64.1% and 34.2% of the A. flavus strains produced AFs and CPA, respectively. Most of the A. flavus strains presented moderate toxigenicity with mean levels of AFs ranging from 100 ng g?1 to 1000 ng g?1. All the CPA-producing strains of A. flavus were highly toxigenic producing N30 ?g g?1 of CPA. Furthermore, 98% of A. tamarii strains produced CPA and over 50% of them were highly CPA toxigenic. With respect to OTA-producing fungi, a high percentage of black aspergilli strains (49.2%) were able to produce OTA. Additionally, most of the OTA-producing isolates were of moderate toxigenicity, producing amounts of OTA from 10 ?g g?1 to 100 ?g g?1. These results indicate that there is a possible risk factor posed by AFs, CPA and OTA contamination of cocoa beans, and consequently, cocoa products.

The bottom line is that chocolate is a high risk food for mycotoxins.

The link to the article he posts is dead (or goes to a main page but doesn't contain the specific article he references), but I tracked it down:

Notably, this article tested for mold on raw cocoa beans, rather than actual chocolate bars. However, I found a 2011 article from the same journal that did proceed to test actual chocolate bars:

Here is one of its conclusions:

"No fungi were isolated from the 75 samples of chocolate bars evaluated. Of the 25 samples of powdered chocolate analyzed, only one showed fungal contamination."

While they found mold in raw cocoa, the industrial process seems to get rid of that issue:

"The low level of fungi in the final product is a result of industrial processing (roasting, grinding, pressing and alkalizing) which basically consists of technological processes that change the cocoa beans into products which actually taste like chocolate and at the same time reduces microbiological contaminants (Beckett, 2008)"

So, chocolate bars might be just fine. Raw cocoa powder would be more the concern. Any thoughts?


  • I just buy various high-quality cocoa powders and use them to make my own chocolate bars using coconut oil as a base. This allows me to make a better, stronger chocolate bar, with less (or no) sugar, for less money. My favorite brands of cocoa powder are valrhona and droste, both can be bought at Whole Foods and both seem to be labeled for international sale. Haven't tried Dave's yet.

    Laboratory support staff by day, personal trainer by night

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