There has never has been any doubt about two things

1. that proper commercial freezing at -40F in vacuum bags preserves coffee over the long term. Sivetz patented this for green and roasted coffee back in the 80s; it's been published in peer reviewed journals; and is unchallenged. Given that the moisture content of coffee, either green or frozen, is too low to cause crystallization damage, there are no grounds for doubting that proper freezing will almost entirely halt all chemical reactions and preserve the coffee.

2. That storing an open or casually sealed bag of coffee in the freezer between uses is detrimental to the flavor since the air exposure and condensation damages the beans.

So the only question is if reasonably careful freezing in a home freezer is more like 1 or more like 2. Given that "reasonable" means airtight packaging and no air exposure during freezing or defrosting, there is no scientific reason to think this is more like 2. And our experiments show fairly convincingly that the zero to minus fifteen F of home freezers does extend the life of the coffee to several months. Minus 40F is said to preserve indefinitely, we never made any claims that home freezing will do this.

Dogshot wrote:I think the outdated notion of keeping coffee in the freezer between uses has made the whole idea of freezing coffee a difficult one to accept.

I think that's it in a nutshell.

Dogshot wrote:I probably would not have tried freezing my coffee if not for the research you have done and shared, Ken - so thanks.

It has changed the way I buy coffee. Now, I go to my roasters/resellers and buy 5lbs at a time, rather than mail ordering in 2lb amounts.

Mark

Same here. While not 5lb amounts, I definitely order more than 1 package or pound at a time.

I was very happy to find this in the FAQs a while back. I was considering ordering in 5lb quantities to save on long term shipping and coffee expense. I knew there was no way to consume that amount before it went stale and I knew that storing coffee in the fridge between uses was bad. I wondered if anyone had tried long term cold storage below freezing. What I found was an extensive study conducted to a standard I never would have considered, with results that were pretty darn clear. I do not have a chest freezer, but I was willing to try this in my home freezer.

I have now been ordering 5lb bags since the beginning of the year. The coffee arrives 2 days post roast. I split it into 6, 1 liter canning jars. 5 go in the freezer on the back shelf behind anything else that may be in there. This is an effort to minimize any ill effect the occasional door opening may cause. The last one goes on the counter to rest another day before use. It usually takes me 3 to 5 days to empty a jar. The original container of unfrozen coffee is gone by day 6 or 7 at the latest. It takes around a month to go through the whole 5lbs. In the time I have been doing this I have not been able to detect a noticeable difference between the frozen and unfrozen coffee, even in the coffee in the final jar. I am not a super taster, but I am quite pleased with the results I have experienced. While I may not be a super taster I am familiar with the difference between the way fresh and stale coffee pulls and tastes. In my experience in my home ice box freezer, fresh frozen coffee when treated with some respect, does not seem deteriorate after a month.

Thanks to Ken for the original post and to Jim for assisting with the follow up. While everyone else's posts seem to make me want to spend more money on gear, this post is actually saving me around 10.00 per coffee order. At this rate I will save around 120.00 to 150.00 on coffee this year.

Another thanks for saved postage costs and less global warming

Split follow-on discussion to Freezing decaf vs. regular roasted coffee.

cannonfodder wrote:The ambrosia from Fresco I left in the pound valve bag and taped over the one way valve to prevent it from gassing in, or out.

I just put a fresh 250g valve-bag of coffee in the freezer to check the things myself. And I have a question related to the condensation on beans... the CO2 that coffee is degassing is non-humid?

CoffeeOwl wrote:I just put a fresh 250g valve-bag of coffee in the freezer to check the things myself. And I have a question related to the condensation on beans... the CO2 that coffee is degassing is non-humid?

As long as you don't add an "H" to it. Hope this helps.

ken

Ken Fox wrote:As long as you don't add an "H" to it. Hope this helps.

yes!! Chemistry was not my favourite subject