David Donde: The importance of home grinding
By David Donde, 2 September 2015
The question is always waiting for me like a goon in the shadows. What espresso machine should I buy for home? Well dude, your partner is probably not going to allow that behemoth to live for long on the kitchen counter. Your huge fantasy coffee machine is going to make way for counter space eventually. That’s if Eskom management doesn’t insist on its forced removal sooner.
The sadness of this dilemma is not in the espresso machine, I share these fantasies, and do in fact indulge in them from time to time. The sadness is that it is off of the mark. A perfect espresso machine with supermarket coffee that is pre-ground is not a shortcut to coffee perfection.
Coffee is ruined by oxidisation. Pre-grind, and that aroma that you smell in the store? Flavour Elvis leaving the building. Beyond that coffee extraction is simple chemistry. Particle size vs brewing extraction time – think contact time between water and coffee. You also need to factor in the temperature of the reaction while water and coffee quantities also have an effect.
Now on an espresso machine, the water temperature (hopefully) is pretty stable. As is the dose of coffee used. So to control the brew time, one plays with the particle size in order to achieve perfect extraction. Only one way to do that properly. Adjust the grind size. This in effect means that a home grinder is an essential tool to coffee extraction.
Beyond that there is an issue with particle size. One wants a roughly consistent particle size for good flavour. So “propeller” grinders are not an answer. Besides smashing rather than grinding the coffee, you will only get an approximation of the grain size you want. Half will be too small, the other half too large, causing all sorts of flavour issues.
The answer is with what we call a burr grinder, a grinder with two blades that a dial or adjuster moves closer and further apart, allowing exact particle size selection. They range from mechanical ones at around R700 to electric home ones for a few thousand to commercial ones starting at R8 000 and going all the way up to R30 000!
Buy the best one you can afford, that is allowed on your kitchen counter, forget the cool espresso gizmo, and invest in a grinder, if only to supply your plunger. Espresso machines will come and go, but a great grinder will last a lifetime. I promise it will be the most rewarding upgrade you can do for your coffee regime!