Mugshot: the precision of coffee machines

Making coffee these days is a craft, right - and not the knitting-needle kind.

Baristas spend ages adjusting their grind, calibrating their extraction times and waving the pourover kettle in a careful swirl to dribble exact-temperature water over unbleached filters in hand-made ceramic cones, working by taste, smell, sight and intuition.

But speciality cafes in Sydney and Melbourne are turning to tech in their search for perfection and consistency.

It starts with a gadget baristas call the Mojo, a digital refractometer used to measure the total dissolved solids (TDS) in coffee.

TDS, according to Jared Lawler of Clement Coffee, is the only real measure we have of coffee. If you know how much water and ground coffee you started with, TDS allows you to put a number on how much coffee stuff you've extracted: the basis of volumetric brewing.

As Lawler explains, TDS is like a dot on a map: once you have coffee tasting the way you want it, the TDS tells you the level of extraction that got you there, so you can get there easily again. He says about 90 per cent of the work baristas do every day dialling in their shots - brewing, tasting, adjusting grind and dose - can be done using TDS measurements, without tasting a drop: a big saving on barista palate fatigue.

Numbers work best if you can plug them into a machine, which is where set-ups like the La Marzocco Linea PB and the Steampunk come in.

The Linea is an espresso machine with a software interface that allows baristas to program a range of variables, including boiler water temperature (to within +/- 0.5C), and pre-infusion and extraction times.

The Steampunk brews filter-style coffee in large glass crucibles. It's programmed and controlled via Google tablet to emulate different filter brew styles to suit different beans and roasts: pourover, siphon and plunger. A Steampunk is already on the brew bar at Brewtown Newtown in Sydney.

Waiting in the wings is the Briggo Coffee Haus, a giant coffee-vending machine that looks like it spits out paper cups full of soft serve but actually roasts, grinds and brews coffee and steams fresh milk to produce the full range of barista-quality espresso-based drinks (look out, Starbucks).

The future of coffee: full of machines that make coffee with machine-like precision, while humans serve it and smile the way only humans can.