Category Archives: Storing coffee

Resting time

I am not talking about our coming vacations 🙂 but about letting the coffee rest between roasting and brewing. How fresh is fresh and should we brew immediately after roasting? These are common questions that I get from my costumers. The first question I answered in a previous blog:

http://www.engrano.nl/blog/2014/08/03/fresh-for-longer-time/

I always recommend my costumers to use fresh roasted coffee and so I sell coffee that is roasted-on-demand which implies that I don’t have a storage of roasted coffee. However, sometimes it happens that i get a coffee order accompanied by an email with subject: urgent. In these cases it takes a bit of explanation to the customer that I really cannot ship that coffee first thing in the morning since I actually first have to roast it.

But to return to the topic: should you brew the coffee immediately after roasting? Personally, I think coffees taste the best not shortly after finishing the roast but after another 2 to 4 days.
During roasting the coffee beans undergo physical and chemical changes. Due to the chemical reactions taking place during roasting CO2 (carbon-dioxide) is produced which is initially retained in the beans. This CO2 will be released over a period of weeks after roasting, the so-called degassing. The speed of degassing is inversely related to time after roasting: fast degassing takes place during the first hours after roasting and slowing down gradually. Adding hot water to coffee will release some of the CO2 that is still bounded to the bean structure and we can “see” this CO2 in the crema formed while brewing the coffee.

If you brew your coffee with an espresso machine then this fact is very important for you. Espresso brewing takes places under high temperature and pressure, so if there is alot of carbon-dioxide left in the coffee beans it would make the brewing process more difficult and can prevent the proper extraction of the coffee flavours. It will also lead to an excessive amount of crema and sometimes the espresso cup may have more crema than actual espresso which is a clear indication that the coffee has not rested long enough.
For other brewing techniques as for instance filter-coffee this can still be an issue since the coffee will swell-up from the release of CO2. In an open-drip filter this wont be a problem but in closed-dripping as a common electrical filter machine it may lead to the machine to overflow.

You can also use the release of CO2 as a freshness factor! If you prepare an espresso and the crema is too thin and even shows holes through which the espresso liquid underneath is visible then you know the beans are no longer fresh, since most of the CO2 has been released already. The same counts for filter coffee: if the coffee remains flat during the brew cycle, the coffee is old.

Old coffee leads to thin, light crema
Old coffee leads to thin, light crema

The coffee I roast and send always mentions the roasting date, which is typically 2-3 days earlier than the day you receive your package. Though it is tempting to immediately open the package and prepare some coffee, it may actually be better to wait a few days more to get the best flavour. Therefore it’s recommended to not wait with your new coffee order until you really run out of coffee, because otherwise you may find yourself in the antagonizing situation that you can’t make your favourite cup of coffee since you run out of the previous coffee while the new coffee you just received is actually still too fresh to use.

Fresh for longer time

Another frequent question that I get from our costumers is how to keep the coffee fresh for longer time. Good question! I sell freshly roasted coffee, so freshness is kind of an obsession because it makes a word of difference. You know what I am talking about if you have tried and compared both freshly roasted coffee and packed coffee that has been standing for weeks in a shelf before you purchase it.
You have noticed that the smell of coffee decreases with time and so does the flavour, the crema in the espresso too.

So, how to store your coffee to keep it fresh? Well, coffee should be kept away from oxygen, moisture, foreign odours, heat and light.
It may sound complicated but it is not, let me explain.

Oxygen and moisture: Roasted coffee is a dehydrated product and immediately after roasting coffee it will start ageing. Contact with oxygen is one of the factors that contribute to shorten the life of coffee. It is responsible from the typical stale flavour of old coffee. Every time that you open your coffee bag your coffee comes into contact with oxygen and moisture. Thus to reduce the amount of times that your coffee is in contact with oxygen I suggest that you keep in a container the amount of coffee that you will consume in a short period of time, one or two weeks. If you buy coffee in a bigger amount then you better first split the coffee into smaller containers.

Due to a higher exposed surface ground coffee can absorb a considerably higher amount of moisture compared to beans. So, water-tide storage is even more critical if you purchase ground coffee. And please, don’t store coffee in the fridge and never freeze ground coffee!
If you store your coffee in the fridge, when you open the container moisture will come in, then you put back the container in the fridge and that moisture will condense into water droplets… dripping in your coffee… not good.

If really necessary you could freeze beans (not ground coffee). You may need to adjust your grinder to a finer ground when you unfreeze your beans. And if you do freeze the beans then you can only defreeze them once and use them.

Heat: Increases in temperature (starting from about 10C) will speed up the release of CO2 and volatile compounds (which include the nice coffee smell that we love).
Light: Light also plays an important role in ageing of coffee, it has a catalytic role in many chemical reactions.

You may have noticed oil droplets appearing in your coffee, especially in dark-roasted coffee. It starts during roasting and goes as the coffee releases gas because CO2 tends to push oil outwards. The problem here is that the oil on the surface of your coffee will also speed up ageing.

So our advice to keep your coffee fresh for a longer but not indefinitely time is to keep it a grease-proof, air-tight container. Consider glass, ceramic, metal or a polymer as used in the Engrano bags. Place the container in a cool, dry and dark place to ensure the full flavour and freshness of your coffee. That’s it!
But even in this optimal conditions please don’t store coffee for long periods of time, the best you can do with your coffee is to drink it and then get some more freshly roasted beans and every morning enjoy the magic of full aroma and flavour in your coffee!

keep this time of containers in a cool place in your kitchen
keep this time of containers in a cool place in your kitchen
Keep this type of container in a dark and cool place in your kitchen
Keep this type of container in a dark and cool place in your kitchen