One of the best parts of the coffee experience is enjoying the rich aroma of freshly roasted coffee beans. But imagine opening up a bag, taking in a big whiff and smelling……fish (more specifically, tuna.) Worse yet, some people interpret this odor as cat urine! I know, the words fish, cat urine, and coffee should ideally never be associated with each other. That would be enough to mentally scar most coffee lovers. If that's happened to you before, you're not alone. The questions like “why do coffee beans smell like fish” or “why does my keurig machine smell like fish” have been posed many times.
Believe it or not, just because your coffee beans smell fishy doesn't necessarily mean something is wrong with the coffee.
Of course, if they're moldy or rancid beans then you should obviously throw them out immediately.
But most of the time, there's usually nothing inherently wrong with coffee beans that smell a little fishy. I remember the first time I was treated to this unexpected aroma while trying a high-end brand of Kona coffee. For those who don't know, Kona is considered a very exotic and premium coffee so it was fair to expect high standards. I was expecting something amazing. As soon as the smell hit my nose, I thought something was really wrong with coffee and was ready to quarantine what I thought were beans gone bad.
Fortunately, after doing some research on why coffee beans smell like fish, I found there was nothing to be alarmed about. The coffee once brewed tasted exquisite without the slightest hint of fishiness.
Why Coffee Beans Smell Like Fish
The fish like smell that comes from coffee beans is caused from chemical reactions that take place during the roasting process. Dark Roasts, which have been naturally subjected to long periods of heat, are especially prone to smelling fishy.
Some have speculated that the presence of could be the presence of Ethylmethylamine which has a strong ammoniacal and fishy odor. The exact reasons for why your specific coffee beans smell like fish may vary from one batch to the next. Sometimes it's due to just the roasting while in other cases the manner in which the beans are dried could have an effect as well. The point is, it's usually not a cause for concern.
While it may go against every olfactory sensibility you have, the fact is that millions of other coffee drinkers have experienced the very same thing and still enjoyed a delicious cup of coffee in spite of it.
Bonus: If you're Keurig or coffee pod maker smells like fish then you'll want to consider checking for mold and descaling your equipment. Read our article on descaling your Keurig for more info.