What does it mean to have moist or oily coffee beans?

The dark-roasted coffee beans are the ones with the oily sheen on the right.

QUESTION:

Just opened two bags of BARISSIMO ORGANIC WHOLE BEAN COFFEE and looking inside bag it was very obvious that the beans are wet or oily; such moisture is a concern for turning rancid or moldy.

In one of your answers, you state: It’s the roasting process that changes everything. From the moment coffee beans come out of the roaster, they begin to lose flavor. That’s because the volatile oils in coffee begin to evaporate, and it is in those oils that much of the flavor can be found. ... Could the moisture I see be these volatile oils and is that a problem, future problem, or no problem?

Please advise!!! Thank you!!!


ANSWER:

It’s impossible to say with certainty, without seeing the actual beans. But my guess is that you are looking at the natural oils of the coffee beans.

Take a look at the photo above. I took it this morning, after reading your question.

The beans on the left are medium-roasted.

Those on the right are dark-roasted. Not only are they darker in color but, as you can see, the surface of the beans themselves are actually oily.

Are your Barissimo beans dark in color? If so, you are probably seeing the same.

Can these natural oils become rancid? Probably, over time. But before that happens you will have likely used the beans anyway.

One thing to remember... whatever the roast and color of the whole beans you buy, you should always keep them in a sealed container. Beans go stale when exposed to the air and lose their finer flavors surprisingly quickly. And those oils will oxidize too.

I hope this answers your question!

Best wishes,

Nick

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