Coffee is enjoyed from variety of brewing methods. Whether it's espresso, pour over, french press, coffee needs to be ground before it can be best extracted to get the best flavours. To save on time, and the minor inconvenience of grinding whole beans, people tend to buy pre-ground coffee. This comes with a few benefits and caveats, and is worth weighing to see what works best for your coffee brewing.
Types of Ground Coffee
Simply put, pre-ground coffee is roasted whole beans, ground into various grind sizes between coarse to very fine espresso. Also, a short mythbuster; Pre-Ground coffee is NOT instant coffee! The distinction being instant coffee is freeze dried concentrated extract of roasted coffee beans.
This level of ground coffee is the finest grind size you'll typically find which is ideal for espresso brewing. The only grind finer is for turkish coffee, also known as extra fine grind.
Fine grind coffee is ideal for Moka Pot, and Aeropress brewing. Typically this grind level is associated with producing a strong black cup of coffee. Not to the extent of espresso, with ideally for a darker roast, with a high ratio of extraction.
For pour over, clever dripper and drip coffee machines, filter grind produces the ideal conditions for coffee to be extracted for water being poured over the top via percolation (and immersion for the clever dripper).
For french press coffee, the most coarse cafetiere grind is ideal for this immersion brewing method, meaning your immersing ground coffee with hot water over a modest chunk of time, usually 8-12 minutes.
Whilst ground coffee is far more convenient, and likely to ground to a high standard from a specialty coffee roasters, the caveat is ground coffee stails far quicker than whole beans. When coffee is ground, a greater ratio of the coffee material is exposed to oxygen, and more aromatic compounds containing flavour are released. This combination means the best coffee flavours are release more quickly than storing whole beans.
As a general rule of thumb, if you consume ground coffee within 1-2 weeks of being roasted, most of the best flavours should stay in tact. However beyond 2 weeks, we advise going whole beans and grinding your coffee with a good quality burr grinder.