Espresso Brewing Guide
Which beans? Specific Espresso roast beans will work best under the pressure of the espresso process
What grind? Use a very fine grind – not all grinders will get this fine (see our notes on equipment here)
Brewing Notes The finer you can extract something, the more surface area the water has access to so theoretically the more you can get out of the coffee. By putting extraction under pressure you are able to work with a very fine grind. This is the key to why espresso is so different to the other methods.
Simple Brew Notes (per single cup):
- Grind 18gm (fine) into the (warm) portafilter basket
- Lock it into the machine, put your cup underneath and hit the brew button
- Hopefully start to see drips at 7 seconds, and after around 30 seconds the shot should weigh about 36gm (if not adjust the grind – coarser to speed up and finer to slow down)
Other Brew Notes:
All machines will have different variations on the following basics;
- Aim for about 18gm beans, ground very fine.
- The espresso machine will target around 93C - 94C extraction temperature. The output volume should be around 36gm (doubled, so you have equal parts water and coffee aka 1:2 brew ratio)
- This extraction should be achieved in something close to 30 seconds (at the standard 9 bar pressure). If it’s quicker, the grind is too coarse so the water pressure is flooding through the coffee grounds too quickly. This will result in an under extracted sour coffee. If it takes longer, the grind is too fine so the water can’t get through quick enough and is in contact with the grounds too long, over extracting the coffee and resulting in a bitter flavour
Milk tips Steaming the milk for your flat white/latte/cappuccino, this takes a bit of practice (you can use water and washing up liquid to save on milk cost) but the basics are to expand the milk with bubbles (small for flat white, big for cappuccino) by hovering the tip of the wand near the surface, offset to one side so that it can spin. The spin evens the air throughout the milk. Once you have the volume you want (first 5-10 secs or so), drop the wand deeper and get it all spinning as fast as possible until it reaches the temperature you’re after. (Either using a simple cheap thermometer, or getting your thumb used to the heat you want. Some like it hot, but after 65C the proteins in the milk start to break down so there will be an impact on the taste, even when it cools down)
Pour the milk over the shot, if its fine enough for latte art (you might need to pour or spoon out the frothier stuff on the top), try to keep the mixture dark by pouring from height and in circles to drop the lighter bits below the surface. When you get 2/3rds to the top, tilt the cup and bring the jug close to the surface. Hopefully you can ‘push’ out a blob of white, then lift the jug higher and stripe up the circle, creating a heart. This will all be impossible if the milk texture isn’t fine enough. Also bear in mind that the frothier the milk, the more air, so the more coffee to milk you have, which affects the flavours.