Heavy conical upper burrs pull the beans down, compressing them until they shatter into smaller fragments to enter the flat burrs, to be sheared into the final grind.
Seventeen grams of the fluff exits the edges of the flat burrs and drops into a chute along the sides of the grinding head. A whirling brass paddle smashes into the coffee, whisking it on a furious circular journey at about 450 rpm until it is forced out a square portal to tumble into the dosing hopper. After grinding, this is the first real assault on our sweet coffee – the impeller smashing it into lumps, bruising the lipids and destroying a little of the fragrance.
Because of the short, pressurized percolation cycle of around 25 seconds, the final consistency of the ground coffee is critical to achieve crema, and preserve the full amount of fragrance the bean has to offer. The flat burrs shear the bean into a complex consistency that looks like snowflakes under a microscope. To accomplish this the flat burrs must remain very sharp and require changing every 500 pounds. The goal of the grind is to achieve the highest surface area of exposed aromatic oils, lipids and sugars to be transported quickly by the brewing water into your cup. The rapid percolation cycle and pressure are the unique characteristics of the espresso method that allow us to preserve the most delicate fragrance through the brewing process.
I like coffee. You know that by now. I’m also very committed to the idea that you can have coffee that’s better quality than the coffee served by 90% of cafes at home (without being crazilly obsessive and buying a commercial machine – but don’t tell my wife).
There are two essential ingredients to good coffee that make even the most rudimentary brewing methods produce a passable cup of coffee. Freshly roasted beans, freshly ground. That’s it. If you have those ingredients you can produce a great cup of coffee just by mixing the coffee with (almost) boiling water.
The freshly ground part requires a grinder. Most coffeesnobs will argue that you should spend more on your grinder than your machine. The grind is the most important variable when producing different types of coffee in different ways. Most coffee snobs say the only way to go is for a conical burr grinder – but I think given a little development of technique (ie figuring out how long to push the button for) even a spinning blade grinder will produce a better coffee than a lot of cafes if you have the right beans.
Lets face it, dud beans=dud coffee. It doesn’t matter what other variables you throw into the mix . Give a World Barista Champion a box of Lavazza beans from the supermarket and they’ll still turn out coffee that tastes stale and muddy.
Getting the beans right means getting the beans at the right time. Ideally 2-14 days post roast. The sweet spot timing wise depends on the type of bean and how roasted they are. The darker the bean the stronger the flavour and the thicker the “body” of the coffee – and the lighter the bean the more complex and tasty the bean is (and the less bitter).
There are two ways to ensure you’re hitting that timing sweet spot – one is to find a roaster who labels their coffee by roast date – the other is to roast your own. Buying roasted coffee is expensive – Coffee Dominion in Townsville roasts wonderful coffee – but charges $8 for 250gm – or around $30 if you buy a kilo in bulk. That’s a lot of coffee to get through in two weeks.
Buying green beans is much cheaper – Ministry Grounds – the online co-op I buy beans through sells green beans ranging from $6 through to $12 per kilo – you’ve got to throw postage costs into the mix – but it’s much, much cheaper. Neil Atwood, who runs the store and the associated blog, is a coffee snob and a church minister. He’s very approachable and helpful. The customer service is great – and all the green beans come with a “serving suggestion” roasting notes to help you get the best from different bean varieties.
Roasting at home is easy. There’s a plethora of information around the web. I got most of my tips from coffeesnobs.com.au (who incidently also sell green beans once a month through a first come first served “beanbay”) and my roasting set up cost me about $40 thanks to ebay and some astute garage sailing. I use a heat gun/breadmaker combo as do many people from the coffeesnobs forum – but roasting simply requires heat and agitation – you can roast beans in a popcorn popper.
Home roasting is cheap, easy, and has that do-it-yourself element that adds a whole lot of self-satisfaction to every cup. And it tastes better too.
If home roasting sounds like too much hassle you could always ask your friendly neighbourhood home roaster and they might do it for you… it’s well worth it.