The Benefits of Freezing Coffee
SUNDAY, 13 MARCH 2022
AUTHOR: MAXWELL COLONNA-DASHWOOD
READ TIME: APPROX. 2:21 MINUTES
We have talked about freezing coffee on multiple occasions. Freezing roasted beans has become a trend to allow for high-end brew bar menus in cafes and also as a way to store coffee at home.
Grinding coffee frozen has its benefits, improving the aromatics and cup profile and also helping maintain cup quality over time. It is much the same when it comes to freezing green coffee and we have recently introduced freezer units at the roastery to implement this storage method before roasting.
Green quality is definitely much more important than roast freshness.
An older coffee that was roasted when the green was at its best will easily outperform a fresh roast of the same green if it had started to show “age”.
The exact time frame in which a coffee is optimal after harvest is not a defined period. When I first got into coffee it was shorter than it is now. Improvements in processing, drying and storage have definitely extended the expected optimal window. Saying this, there is definitely coffee and origins that buyers and roasters are more wary of in terms of showing age, such as Honduras and Mexico.
The exact science isn’t fully defined but water activity and drying appear to be key causes, combined with the resulting storage. Frustratingly, there are also factors outside of our control, such as coffee being delayed at a port somewhere around the world, meaning it lands already tasting agey.
This side of coffee has always made it a very different experience year to year, where previous harvests are only memories! George Howell, an American coffee pioneer, started freezing green coffee and presented some fascinating taste comparisons of a Kenyan producer. Two harvests, 4 years apart, were presented side by side and the older harvest scored higher. This was because George had been freezing green coffee and much like wine and other single crop products there are good years and bad years in terms of harvest and agriculture. The older lot was a “better year”. This potential to freeze green coffee and then defrost and roast a previous year's harvest is very exciting.
Frozen storage isn’t necessarily a practical solution at scale for all green coffee, but it makes a lot of sense for rare and small lots and this is how we are using our freezers at the roastery.
The green coffee for our next Limited Release, Chilled Cherry Gesha, is currently in the freezer awaiting launch.
This is very much an optimal storage method for a coffee, but I also feel excited to start freezing small amounts of our favourite coffees, allowing us to revisit them in the years to come. We can then re-showcase our favourite coffees or compare them to different year's harvests. Of course this requires the patience to not drink them in the meantime!