The coffee served at Prufrock and several other cafes is now so good that despite shelling out £100 on a De Longhi machine, my home attempts are a bitter disappointment. I’ve come to up my game but the sheer coffee geekery here has me feeling out of my depth. A blackboard advertises a “milk texture” class (sold out) and in the training area, all polished counters and prototype Simonelli machines, Challender casually flings about such befuddling notions as brew ratios, volatile aromatic gasses and TDS (total dissolved solids). Some intense hours later, I emerge with the lowdown on getting the best out of any machine.
The coffee
Decent coffee, like the stuff Prufrock uses from London roasters Square Mile, comes with a roast date. “Between about nine and 11 days after roasting is when we get really excited about the taste,” says Challender. Their standard espresso is made from capao, a Brazilian single-origin dark-roasted bean. Dark roasts tend to be more complex, with chocolate and caramel flavours; lighter roasts are more fruit and florals.
The recipe
The drink you end up with depends on water temperature, dose of dry coffee, amount of espresso you’re making, the time it takes the machine to produce your shot, and grind consistency. You’ll need a small set of digital scales, and a timer to record the recipe.
Temperature
Prufrock’s machines are set to between 92C and 96C. Some domestic espresso machines don’t hold their temperatures as consistently as commercial behemoths. Perfectionists can find instructions at home-barista.com for pimping machines with a precise temperature control (a PID). Or accept your limitations and get the rest right.
The dose
“We most like the taste of our 30ml double espresso,” says Challender, “when it uses 18g dry coffee, so that’s what the coffee baskets in Prufrock’s machines comfortably hold.” A traditional Italian 30ml double espresso is made with a 14g dose.
Extraction and the grind
Challender prefers the coffee when it takes 30 seconds to extract – that’s 30 seconds between switching the water flow on and off again. Timing depends on achieving good grind, which requires frequent adjustment as no two batches of beans are the same and even a change to the temperature of your grinder burrs (burr grinders trump blade grinders for evenness of grind, and won’t overheat and cook your coffee) will make the fineness fluctuate. You need full control.
Perfecting your recipe
All of the above differs according to your machine, coffee and palate, so experiment. Once happy, keep an eye on the extraction time – if it comes through quicker than usual, your grind’s probably too coarse.
Read the full post at TheGuardian.com (http://www.theguardian.com/lifeandstyle/2012/may/09/how-to-make-the-perfect-espresso)
Ordinary Bea 