Frozen Beans: A Rebuttal

Frozen Beans: A Rebuttal 

The New York Times posted a story (read it here:  on actual scientific research into coffee grinding, to the effect that freezing coffee beans before grinding would improve flavor. Clearly they had not read my page on Coffee Basics ( explaining why grind matters to taste. Sigh. Nevertheless, the recommendation to freeze before grinding could be a bad idea, so here is what you need to know:

1. Do coffee beans grind more uniformly if frozen? If you use a decent burr grinder set for the kind of brew you are making, beans are being ground fairly evenly without freezing. Further, freezing beans actually could hinder the extraction process by dragging down brew temperature, so DON’T. (FYI, please read my pontification on Grind Matters.)

2. No substitute for using the right equipment. If you are using a whirly-blade grinder, freezing your beans might help the “coffee dust vs coffee rocks” situation, and you might reduce unwanted bitterness that way. You will never obtain a consistent size grind using this method, IMHO, so don’t expect miracles when the “miracle” is actually a decent burr grinder.

3. So if you DO freeze your beans...If you do want to freeze your beans ahead of grinding, you might have to allow the ground coffee to return to room temperature before brewing. I don’t know if letting your ground coffee sit exposed to air for a short time prior to brewing will appreciably impact flavor. Technically it should, but I doubt that it would be a bad trade-off in practice. The bigger threat is bitterness from over-extraction of the very small particles.

4. Something smells off here.  What really bothers me about the suggestion to freeze your coffee is that refrigerators and freezers are dangerous places for coffee due to the danger of flavor contamination and staling from exposure to air. Be aware that you cannot keep coffee fresher longer by freezing, but you could wreck quality beans by doing this. Stay away, please!

5. Get trustworthy guidance.  Now is a good time to remind everyone that NanoRoast has literally pages of guidance on maximizing coffee enjoyment. Why not refresh your knowledge now?