Having to stay at home during lockdown or shift to reduced hours leaves plenty of spare time in the week. We asked London-based coffee expert Ed Yarnton about what he would recommend baristas get up to if they have time on on their hands.
Ed is well qualified to offer perspective - he’s been involved in the fully supply chain from sourcing to setting up coffee shops in London. He currently works as a New Business Manager at Assembly Coffee in Brixton - keep him in mind as you see these bags make their way to coffee shops across the UK. Be thankful too - they’re a good bunch.
First off, there is a small stack of books that Ed recommends all barista become familiar with:
- The Professional Baristas Handbook by Scott Rao provide
- God in a Cup by Michaela Weissman
- Devil's Cup by Steward Lee Allen
Additionally, three how-to guides on steaming milk, pour a heart and improve your latte art provide an entry-level understanding, while Espresso Extraction: Measurement and Mastery by Scott Rao goes deeper.
We’re pretty pleased to publish these steps, straight out of Ed’s back pocket - Espresso Making 101:
- Remove portafilter from group head
- Purge group head
- Empty basket and clean with cloth
- Dose coffee (note weight)
- Distribute evenly using the tapping method. Even distribution is vital in even extraction!
- Tamp evenly and firmly until the grounds stop compressing
- Ensure there are no loose grounds on the basket edges (wipe off with hand)
- Insert portafilter
- Stop between 26 and 34 seconds.
What we’re looking for, from Ed:
If grind and dose weight are consistent extraction should yield between 32g and 45g depending on coffee in 26 to 34 seconds. The coffee will start slowly, with a thick, dark brown crema and slowly lighten in colour, known as ‘blonding’ and speed up towards the end. The taste will be sweet, creamy and balanced - highlighting the unique flavours of the coffee.
If the coffee runs fast, the crema becomes white and thin quickly - you have under extracted the coffee and it will have a weak and almost sour/salty taste to it, causing a ‘puckering’ in the mouth. It is likely to have a ‘thin’ body and weak crema. It may also be an indication of channelling (see below).
In this case, look at your dose amount, tamp pressure and evenness.
Once you have confirmed dose is correct and it still runs fast, look to grind size – too course. Only make the grinds finer as a last option.
If the coffee runs slowly the crema will be very dark and the coffee will look thick. This will be very strong and over extracted, resulting in bitterness and a drying sensation of the mouth. Perhaps you have over dosed, or the grind is too fine. Work back from the dose before making the grind courser.
Channelling is caused when coffee has not been distributed evenly and/or tamped correctly, resulting in the water finding a path of least resistance. This will cause over extraction through that ‘path’ and under extraction in areas the water did not pass through – resulting in bitterness and sourness in the cup.
The shot will likely look thin, fast and watery when extracting and lack crema in the cup.
Thanks to Ed for sharing these notes. You can find him posting regularly on Instagram via @edyarnton.