The root of great coffee is firstly in the choice of coffee beans and their roasting, and secondly in the subtleties of the way those delicious coffee oils are extracted. Coffee making machines can either hide the complexity of extraction – think Nespresso capsule machines – or give you the full range of skilful adjustments – think more coffee geek and an expensive mini café style espresso machine. Maybe it’s like the difference between ‘house wine’ and ‘fine wine’. The ROK espresso maker works in both modes, catering for no-fuss hit-me espresso and also the infinite adjustment of the coffee geek looking for that ‘god-shot’. 

So, what are the ingredients to great coffee? Well, higher pressure went through a phase of being cited as desirable, with a bit of an arms race between manufacturers, but today’s trend reflects the reality that 6 – 8 bar is ideal for great taste. And that doesn’t require an electric pump.

The main taste difference comes from the type of beans, the grind and the freshness of the ground coffee ( but don’t worry if you don’t feel up to mastering all this in one go – there are shortcuts to success). Bean flavours are as varied, and subtle, as wines. For some, it’s simple enough to find one or two you really enjoy, and stick to them. For others it’s an infinite playground of exploring tastes. Each to his own. But dally with freshness and you risk a poor experience (dare I say, similar to the lottery of quality I find in global coffee shop chains compared to passionate local café’s?). So much so that we adapted our patented ‘O-ring’ technology to create the Zero Jar which simply squeezes air and the harmful oxygen out of your bean or ground coffee storage.

Then comes the question of grind quality, type and fineness. It all matters since it defines the surface area of interaction between water and coffee oils, which is key to extraction. We created a human-powered grinder that majors on a great fluffy texture and remarkably consistent size of coffee ground – vital to avoiding ‘channelling’ as the hot water is pressed through the coffee. Electric grinders can do the same job - but not the cheap ones. Of course, you can buy pre-ground coffee to get this part right.

I promised short-cuts. Not everyone wants to become a coffee expert and explore and fine tune all these elements – at least, not to start with. And sometimes even the geeks just need a quick simple shot. This is why we offer a short-cut to success with a pressurised portafilter for the ROK espresso maker – just chuck in any old grind size and away you go, no fine tuning required, no tamping or preparation of the puck. 

And if you want to read up on the science and why huge pressure isn’t helpful, why not start here with a pretty heavy treatise which includes discussion of ideal pressures.

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