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Coffee beans, like many other agricultural crops and foods (oats, corn, peanuts, rice, wheat, cocoa, grapes etc.) are susceptible to contamination with mold. While some molds are harmless, others can produce substances called mycotoxins, such as ochratoxin A (OTA) and aflatoxin B1, which can be harmful. However, amounts of molds found in roasted and brewed coffees do not appear to pose a health risk. In fact, you may be exposed to more of these mycotoxins from eating other common foods. See the full answer >>

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March 4, 2015

I have a Kerrigan 2.0 does anyone have any suggestions on cleaning it to avoid the mold problem?

April 11, 2018

If you are speaking of a machine similar to a Keurig, I add 2 drops of 35% food grade hydrogen peroxide. I calculated this amount to produce a final concentration between 100-300ppm which is safe to drink (also much of it is destroyed in heating). This prevents algae formation in the reservoir and hoses.
April 19, 2018

Hi Anthony - The NSF provides some guidance for cleaning coffee makers, found here:

November 14, 2020

Copied the link above, it says that page does not exist.

MAX 592
March 4, 2015

Is there a chance of mold in roasted coffee stored in the freezer compartment of the refrigerator for several months?
March 9, 2015

Hi Max - Just as with other foods, freezing coffee should de-activate mold spores (they won't grow), although it won't kill them.

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