Posted in Kafevend Blog
Last week, we had a look at how coffee is roasted and the attention to detail taken in the process. Today we are carrying on our little series on coffee and examining the penultimate step before making a cup- the grind. Whilst as with roasting you might think initially that there isn't much to it, the way you grind your coffee does have a big effect on the final product.
The first thing to consider is what you are going to grind your coffee with. There are four major methods of grinding coffee:
Roller grinding: This method is the one typically used on an industrial scale. The coffee beans are fed through large pairs of corrugated rollers, producing ground coffee en masse.
Pounding: This method creates the finest of grinds and reduces the coffee beans to almost a powder by using something such as a pestle and mortar.
Chopping: Though cheap and readily available, the chopping method- which uses blades to grind the coffee- is not always recommended as it is very difficult to produce a uniform grind which is vital to producing a good brew.
Burr grinding: The most likely method used if you like grinding your own coffee, burr grinding uses two counter-rotating, jagged and cog-like wheels or cones to produce ground coffee. It results in a much more uniform grind over chopping, and some machines can vary the fineness of the grind.
So that's how your coffee gets ground up, but why the need to grind it in the first place and how does the coarseness of the grind affect your brew?
Different ways of making coffee require varying levels of fineness in the grind. It all comes down to surface area- a larger surface area, as you get in a finer grind, will extract more quickly than a coarser one. So espressos require a fine grind, compared to the coarse grind needed for a French press. If a fine grind is exposed for too long to hot water, it will over extract and produce a bitter and strong drink- conversely, not exposing a coarse grind to hot water for long enough leaves you with an under extracted and weak drink.
The finest grind of all is used to make Turkish coffee, utilising the pounding method mentioned earlier. This powder like grind is essential to a successful brew. Turkish coffee uses a pot called an Ibrik, which tapers towards the neck. Water goes in first with the coffee on top, creating a seal. When it is heated, the water will bubble up through and extract from the finely ground coffee. This process has to be repeated three times and removed just as it starts to boil. The technique is complex enough to warrant its own competition, where competitors from around the globe have to perfect both the brew and the grind to come out on top.
We hope you've enjoyed our look at coffee over the past few weeks, and we hope you'll join us again next week when we begin anew and examine our other favourite drink- tea.