JohnB. wrote:I use a frost free storage freezer set to -5*F. The roasted beans are vacuum sealed in canning jars. This set up keeps the beans usable for about 6 months.

This is representative of the vast bulk of the anecdotal evidence collected over many years of fevered discussions on multiple venues regarding low temperature food storage including coffee. Works fine for about 1/2 year in just about any freezer that is capable of making ice cubes. The colder the freezer is the longer it lasts and colder means all the way down to absolute zero. There are huge usenet archives on this subject.

another_jim wrote:-40 (F or C) is the ideal, based on Sivetz's work.

His patent says "less than −40 degrees F".

I think colder is better but not in a linear way. Even putting it in the refrigerator is better than leaving it out. An extra 5° probably won't make that much difference. But other than some small effect on electric usage what's the downside of setting the freezer as low as it will go?

I keep mine in the storage freezer which runs around -15-20F as I recall. I have kept greens vacuum packed and frozen for a couple years. Roasted coffee rarely makes it past 2 weeks, usually one week. I also quit purchasing so much green coffee. I get it in smaller 5-10 pound batches at most and enjoy the seasonality.

jpender wrote: But other than some small effect on electric usage what's the downside of setting the freezer as low as it will go?

Logically, it would shorten the life of the compressor, all else being equal. Don't know how much, though.

Here's a related question. If you received roasted whole beans the day after it was roasted, would you freeze it right away and then let it age for a few days in room temperature just prior to use, or would you let it age at room temperature for another 5-6 days, let all the gas escape, and then freeze?

Frozen coffee will age, although quite slowly, so when I'm freezing a batch, I'll let it offgas for a couple or 3 days after roast (in a cool, dark spot), and then package and freeze it. I find that when I pull it out several weeks later, it'll be nearing its peak. My batch size is 8 oz, so it all gets drunk within 4 or 5 days, typically, before any apparent staleness sets in.

As cold as you can set it.

As mentioned, three months is my use it shortly cutoff.

I did an uncontrolled experiment and put three bags of roasted coffee in my laboratory -80 degree freezer. Two were my home roasts and one commercial They were in one way valve bags that were degassed or rested for three days. Two years later they were as best I could tell totally unchanged from the day they were frozen. -80 is close to suspended animation for coffee. I did not try liquid nitrogen

If Elon Musk is reading this thread, he's probably already concocting a scheme to store warehouses of roasted coffee on the dark side of the moon, where it's -382F.

Balthazar_B wrote:If Elon Musk is reading this thread, he's probably already concocting a scheme to store warehouses of roasted coffee on the dark side of the moon, where it's -382F. :P

Yeah but when the sun rises it gets really hot there so you'd have to drink the coffee within a couple of weeks anyway.