How long can I keep beans frozen before they are unuseable?

Pompeyexile

Was having a root around in my chest freezer this morning and there hiding at the bottom I found these…

I do not for the life of me remember putting them in there, but as you can see from the date they were roasted in 2017 which is when I must have bought them.

So, will they still be useable? If so, do I measure out a dose and let them warm up to room temp before grinding or grind from cold?

Or Bin them?

I’ve heard that Mammoth meat found frozen in the Russian Tundra for a couple of million years has been tasted and nobody died from it, so maybe 4 or five years isn’t quite so bad.

I hang my head in shame!

Dumnorix

Pompeyexile
Love the new DB in the background! I will be very interested to hear the results.

Doram

Pompeyexile I do not for the life of me remember putting them in there, but as you can see from the date they were roasted in 2017 which is when I must have bought them.

Read about some coffee experiment that showed 90 days in the freezer was equivalent to 1 day in room temp. If true, and providing you froze the beans on roast day (which of course you did), they should be like 20 days off the roaster now (5 years x 365 days divided by 90) - so perfectly rested for espresso! ;-)

Flat_Eric

Don’t just bin them! Try grinding a batch from frozen and thawed, try different brew methods. This is a great opportunity for experimentation, let us know your findings.

dutchy101

Provided they were frozen not too long after roasting, they will probably be fine - but might be worth only defrosting them in small quantities, in case they very quickly stale up after defrosting. Let us know how you get on.

On a former board, @DavecUK did an experiment with some 5 year old coffee that he found in his house (if I recall correctly this had not been frozen). He drank a cup and lived to tell the tale….

MediumRoastSteam

I’ll drink it for sure. Or at the very least, try it out.

Pompeyexile

Well, I opened the Indonesia Buana Mandiri and weighed out 18 gramms and put the rest back in the freezer.
As I’ve sold my Brasilia grinder and the Sage is all packaged up ready to go if that gets snapped up too, I was left with my ROK grinder. Had it set for what they recommend for espresso and….. it was very very bitter! It ran so slow it almost choked the machine.

Another 18 grammes adjusted the grind setting so not quite so fine, tamped a little lighter… Ooh, now that was better, the bitterness really toned down and a hint of sweetness. Still ran a bit slo though.

Another 18 grammes backed, off another notch on the ROK setting and….like night and day. It ran nearly perfectly resulting in only a slight hint of bitterness, but my goodness the sweetnwess really came through.

Now OK, I didn’t get the tasting notes of dark chocolate (although maybe that was the hint of bitterness), baking spices (wouldn’t know what they were…All Spice? Nutmeg? Mixed Spice? if so definately not) but as for the dried fruit sweetness… Oh yes!

Now since starting this journey, I have never had an espresso shot I could honestly say I enjoyed… unless it had lashings of milk in it. In the past, that may well have been down to my incompetence rather than the equipment. But, with the ability to pre-infuse properly both pressure and timewise and the machine ramping up rather than just hitting the full pressure immediately and being able to adjust the brew temp more accurately, which the Sage does effortlessly, must have something to do with it.

I was also very surprised at just how fine the ROK grinder can go and how adjustable that is too.

So, whilst the first lot of beans seemed OK after being in hibernation for five or so years, I know my palet is nowhere near as refined as some of you more experienced chaps/chapesses who if tasting them, might have a competely different opinion. To me though, they gave me a taste experience I have not yet had several years in, on my ‘real coffee’ journey and are therefore, too good to go to the compost heap.

Oh, and all tests were done from frozen.

DavecUK

Doram I drank some coffee that was 6 years old stored in a valve bag at ambient temperature in my workshop…… @MWJB Mark tried this coffee as well.

It led me to the conclusion that although the coffee may lose some (well a lot) of je ne se quois…it seems to be almost immortal.

Pompeyexile

So, not so much a Chateauneuf-Du-Pape, more of an Aldi bottom shelf special.

-Mac

I think freezing helps, too. Parsnips and potatoes that have been par-boiled and then frozen taste sweeter after they’ve been cooked from frozen. Something to do with the water inside crystallising. Don’t see why that wouldn’t apply to coffee beans too (though it’s less noticeable).

tompoland

I regularly grind frozen beans and that works very well. But I’ve noticed a deterioration in flavor and body if I let them defrost before grinding. They are still OK to drink just no longer stunningly good. No idea why but I read an article (so it must be true?) that defrosting sets of some sort of chemical reaction.

Being coffee, many will be more than happy with defrosted beans. More power to them.

LMSC

tompoland I regularly grind frozen beans and that works very well.

How do you deal with the risk of moisture impacting the burrs in the bigger scheme of things?

tompoland

Not sure there is any moisture. I probably should have explained that I vacuum seal individual 18 gram doses. Umm, yes I definitely should have mentioned that!

I guess it might be an issue if I was opening a typical bag of beans every day to take a dose out and then resealing. Even then though I don’t think there will be excess moisture.

Then again, a lot of people use RDT i.e. misting the beans with a fine spray to minimize spraying. I would be a little concerned about moisture retention in the grinder which is why I have avoided RDT. I’m not an expert in this area but I can’t imagine water and steel is a great combination generally.

tompoland

PS the bags are recyclable (I get asked that a lot so I thought I’d pre-empt the question :-) )