Resting Coffee
There is a myth in the coffee industry that all coffee starts to become stale and lose flavour after a few days, but this is not always the case. The aromatic compounds, which give coffee its flavour, often take time to develop after roasting. But, there are few scientific studies which provide robust insight on the time-frames needed to develop optimum flavour.
Our experience with our own freshly roasted coffee suggests roasted beans can reach a delicious taste profile within minutes, but this is rare. Some reach an optimal taste within hours, but most coffees are best if left at least 1 day, and many are best left 7 days. This depends largely upon the variety of the bean and the degree of roast. Some varieties, notably our espresso blends, are at their best 5 to 6 days after roasting. This process (holding off on brewing for a specific period) is usually called "resting."
Roasted beans give off a considerable quantity of carbon dioxide (CO2) while resting; this emission continues at a reduced level over a couple of weeks. This CO2 release serves as an indicator of bean freshness: just-roasted beans will create a goody quantity of froth when brewed or extracted for espresso, whereas stale beans will create almost none. In the coffee trade, this particular froth is called "bloom."
At Spiller & Tait all our coffees are packed within minutes of roasting into mylar plastic bags, which have a foil lining and a one-way valve. These bags are ideal short term storage for freshly roasted coffee. They protect the coffee during the resting period by releasing CO2 through the valve while preventing contact with Oxygen in the air, which causes aromatic compounds to dissipate quickly and reduce flavour.
We also time the dispatch of our coffees so that most of the resting occurs during the period of transit to our customers. By the time a bag of coffee bought via this website reaches you, much of the resting is complete, which can sometimes be evidenced by a build-up of CO2 in the bag.
Our goal is for all our coffee to reach customers within 7 of roasting so the coffee has ripened to its optimal taste profile. By this time most coffees will having lost much of their CO2 and any negative combustion tastes created during roasting. How you then choose to store your coffee will also have a significant impact on its flavour. Follow this link for more advice on Storing Coffee.