Storing Roasted Coffee

Have you ever had a cup of coffee at a cafe you often frequent only to find something is off? We run into this a lot!  Sometimes we ask questions and find out that it is simply a novice barista. Sometimes we realize that a setting with the espresso machine/pour-over system/French press/etc is off (normally a water temperature problem).  Sometimes we find that the grinder needs to be calibrated. But most often we find that it is a storage issue.

All the attention possible can be given at the farm, in the roastery, and by the barista only to find that the manner in which the coffee is stored is the culprit for a bland cup. Light, heat, moisture, and oxygen are the elements that need the most attention when considering how to keep your coffee the freshest. We have seen some beautiful displays of airtight artisan glass coffee containers that cafe’s use to display their beans only to place them on a counter in direct sunlight. The containers are rated to keep all oxygen and moisture out but the light will still adversely affect the coffee. We have seen others place the coffee in well engineered stainless steel canisters that keep out light and oxygen but then place them in a cooler to keep the beans chilled. This is another attempt to protect the beans that does damage because refrigerating them increases moisture.  Many times though, it is isn’t necessarily a problem in the immediate environment it is simply a storage medium issue.

From May to September 2018 Blue Bottle conducted a fascinating experiment trying to identify the best way to preserve freshly roasted coffee. For the analysis they not only controlled the environment to minimize the exposure the beans would have to light, heat, moisture, and oxygen, they also placed the coffee in three different types of packaging. They wanted to gauge the resulting effect on the beans if the greatest concern for environment was tended to how much responsibility for freshness was due to packaging. The different types of packaging they used were:

A compostable paper bag (Blue Bottle’s standard storage method), opened once a month to take a sample
A GrainPro 15-kg Ultra-Hermetic zipped bag, opened once a month to take a sample
A GrainPro 15-kg Ultra-Hermetic zipped bag, which remained sealed throughout the entire five-month trial

With the standard compostable bag used by Blue Bottle they found that the cupping score dropped from 86 to 79 over the five month period. With the GrainPro bag they found the cupping score dropped less drastically. In the ultra-hermetic bag where they were sampled each month the scores only dropped 5 points over the same time period (from 86 to 81). Whereas the beans that were not opened a single time during the experimented only saw a 3 point change during the five months (86 to 83). Needless to say, the beans with the least amount of oxygen exposure won the day. It is important to note that regardless of the storage medium freshness was lost.  Drink your coffee – best not to let it linger!

Leave a Reply

Your email address will not be published. Required fields are marked *