Our espresso machine is something a little bit special. In fact, its so special that it's one of only three of its kind in the UK. It's called the Slayer and it makes espresso unlike any you have probably tasted before. If you'd like to know how, and why, read on! The Slayer was hand built in Seattle, the home of three of the world's best espresso machine manufacturers. Along with Slayer, Seattle is the home of La Marzocco and Synesso. La Marzocco is the Godfather of espresso machine manufactures; they're of Italian origin, but they now manufacture all their machines in Seattle. Synesso and Slayer are made up of ex-La Marzocco engineers. Essentially, the best brains in the world of espresso machines.
What makes the Slayer so good? Well, it's mostly down to its simplicity. It is a completely manual espresso machine, no buttons, no automatic dosing, just a paddle and a lever.
So, the important part is the paddle. This controls the pressure of the water that is forced through the espresso. With the large majority of espresso machines, you press 'on' and water is forced through a puck of finely ground coffee at around 9 bars of pressure. The Slayer allows us to vary this pressure. This brings out flavours and textures in espresso that no other machine is able to consistently produce.
More precisely, when we pull a shot of espresso at Brew Lab, we first 'pre-infuse' the coffee for about 10-20 seconds. The Slayer pushes water into the coffee at a low 5 bars of pressure to, in a way, prime it. The low water pressure blooms the coffee readying it to release more flavours and a very different texture than would be achievable were you were to simply pull a shot at 9 bars.
Pre-infusing helps us to recreate the kind of pressure profile you get from a lever espresso machine, only more consistently. It enables us to find a sweet spot in coffee that has previously been extremely hard to nail. It's hard to explain in words, but when we first tasted some single origin espressos at Has Bean, brewed on their Slayer, we knew we just had to bring this machine to Edinburgh.
You can get even more experimental with the Slayer's pressure profiling. Bringing the pressure back to the low position towards the end of a shot will bring out more sweetness and help to reduce acidity, but that's a topic for another blog post!
On top of pressure profiling, the Slayer is extremely temperature stable. This is very important for producing espresso in a commercial environment. If you're knocking out three shots a minute at peak times, you need your machine to stay stable at the same temperature for the duration.
And here are some pictures of our Slayer being built in Seattle.