Updated: Apr 10, 2018
As soon as coffee is roasted it starts to lose freshness. Therefore, storing coffee correctly is important for maintaining a high quality cup.
Fresh coffee with the roast date stamped onto the bag is how we should all be receiving it. We therefore want to ensure we get the best out of our coffee and keep it fresh for as long as possible; you wouldn't leave bread out without sealing it. Exposing coffee out in the open, grinding long before use and placing it under the sun are all perfect ways to kill freshness and make your coffee taste flat and stale. Moisture, oxygen, heat, light and time are all important control factors in storing your coffee.
Moisture – Keep your coffee from damp conditions. Storing coffee in the fridge or freezer is acceptable but not advised. Opening up a container allows air to enter and putting it back in the cold will cause condensation. A cool, dry cupboard is a better option. Furthermore, once coffee gets wet (when not brewing) it will spoil immediately. It also provides the means for fungal contamination.
Oxygen – Airtight containers are a must. Oxygen causes coffee compounds to break down, releasing aromas and flavour. This makes for a friend when brewing but an enemy when storing. Vacuum storage containers are a worthy investment to avoid staling. Also, ground coffee has a greater exposed surface area, allowing oxidation to happen more rapidly. Only grind enough coffee for as you use it.
Heat – Storing coffee in a hot environment causes compounds to break down. However, don’t just look out for heat. Temperature fluctuations can cause condensation and so finding a place with a consistent temperature is imperative.
Light – Direct light is also damaging to coffee. Be sure to store your coffee in a dark place.
Time – Try to consume your coffee within 2 weeks after its roast date, which should always be provided. Most coffee is packed in vacuum-sealed bags with a valve, letting carbon dioxide escape (emitted after roasting) but not allowing air in. If you can’t finish your coffee within the 2 weeks after roasting, then 2 weeks after opening the sealed bag is also a good guideline.
Main storage points
Store your coffee in a cool, dark and dry place where the temperature is constant.
Only grind the amount of coffee you are about to use.
After receiving your coffee, try moving it into a large air-tight container and open it as infrequently as possible. (Perhaps use a separate container for daily use.)
Only buy enough coffee as you can consume within 2 weeks. Coffee subscriptions are great for receiving fresh coffee when you need it.