Freezing coffee can have great benefits - however, if done wrong, it can ruin your coffee.
Freezing coffee preserves the life of it. It effectively stops the aging process (aging is still happening, but far slower).
The other benefit to freezing coffee beans is that it can give a more consistent grind profile. This means that the temperature of the room will have much less of an effect on your final cup.
To properly freeze coffee, you have two options.
Firstly, with an unopened bag, you can push all the air out of the bag, place tape over the valve (to stop anything going into the bag) and place in your freezer. When you are ready to drink the coffee, take the bag out the freezer and leave it to defrost overnight. It is important not to open the bag at this time.
This method is great if you have received a lot of coffee, and wish to preserve some of it for a later date.
The other method you can use to freeze coffee is to individually dose it. This involves taking small doses of 15g, 20g or however much you brew with at a time. Place these into airtight containers with as little air as possible. The best results come from vacuum sealers. Ziploc bags can also work. Place these in the freezer, and when you are ready to brew, simply take your coffee, and grind it frozen!
We have had 20+ month old coffees that have been frozen in vacuum sealed bags, and they have brewed and tasted like they were a week old!
The science behind freezing coffee is constantly being evolved, so this is a particularly exciting time to start looking into it.
Photography by Michael Clement: https://www.michaelclement.co.uk/