While it is difficult to define an exact set of instructions that will ensure the optimum performance from any combination of espresso machine, grinder, beans, and individual skill, not to mention personal preferences in taste, there are definitely some principles which if followed will eliminate 80% of the frustration as you get started with espresso.
I will make a start on this now and complete as time permits. If you need more answers before i finish it do get in touch.
1. Water: use Volvic. it is readily available in Europe at least and has a good composition for espresso. equally important it won’t leave your expensive espresso machine looking like the inside of a cement mixer that has never been washed out after 12 months of use. yes it costs a little bit, but it is very inexpensive insurance if you live in an area that has limescale in the town water supply. yes you can descale your machine, but if you believe nothing else on this blog please believe that a de-scaled machine is never as good as a machine that has not allowed to become scaled in the first place. Use Volvic from the very first shot today, and every day. Do not think for a moment that other waters, e.g. Evian must be ‘about the same’ as Volvic in composition. They are not and will scale you machine faster than even London tap water. Oh, and one final point, using the standard Brita carbon filter jug does not have any significant softening effect and will not protect your machine from limescale. The Brita Maxtra filters do soften your water, but if you live in an area with hard water like London the softening resin will quickly be exhausted – budget on changing these filters at least monthly – our water hardness test kit is the only sure way to know when a filter needs to be changed
2. Digital scales that measure to 0.1g accuracy or better: these are inexpensive and essential in equal measure.
3. Don’t fall into the trap of thinking you can be a top of the line espresso machine and use pre-ground coffee with it and expect a satisfying espresso. Coffee that has been freshly ground in a high quality grinder is more important than the espresso machine itself. Pre-ground coffee will disappoint regardless of how good your espresso machine is.
4. Following on from (3) above ensure you get freshly roasted whole coffee beans that specifically state that they have been roasted for espresso. Using coffee beans not roasted for espresso will generally disappoint.
5. Fill your espresso machine reservoir with water and heat it up in accordance with the instruction manual that came with your machine. If it is a new machine fill and empty the machine once or twice to ensure all the debris from the manufacturing process has been pumped through.
6. When your machine is up to temperature grind yourself 8g of coffee is using the single basket or 16g if using a double basket. If you can fit these amounts in you are likely to be grinding too coarse. For entry level machines you may want to drop down to the traditional measures of 7g for a single basket and 14g for double basket if you are having trouble fitting 8/16g in the basket.
7. There is more than one way to do most things in life. For us careful distribution of the grinds in the portafilter is much more important than the tamping step that follows. Clumping doesn’t bother us nearly as much as it does others. If you study what happens when water comes into contact with the puck you will understand why – the water is absorbed into the clumps and the expansion of the grounds that follows blows the ‘clump’ apart. The much feared ‘channelling’ isn’t the result of clumping in our experience.
Poor distribution of the grounds and a high degree of variance between the shape and size of the coffee grounds will cause channelling however, and an expensive grinder addresses the second cause of channelling but not the first. Rather than smashing the coffee bean in a vast array of sizes and shapes with relatively blunt burrs and high spindle speeds as occurs in an entry level coffee grinder, the burrs are sharp, the spindle turns much more slowly to reduce the likely hood of smashing the bean, trying to achieve a milling action instead where grounds of roughly equal size and shape are taken from the bean with contact with a multiple number of burrs.
Anyway, tamping. In terms of a tamper all you need is a tamper that is between 0.5 and 1.0mm smaller in diameter than the nominal diameter of the portafilter of espresso machine. So, for a machine like the Olympia Cremina with a nominal portafilter size of 50mm you want a tamper with a diameter of between 49.0 and 49.5mm. We dislike tampers with shallow verticals. Deep verticals assist in keeping the tamper vertical in the port filter basket, like a piston running in a cylinder; you want all the help you can get in this area. Secondly we have no time for the almost limitless variations of face profiles of tampers. Que outrage from baristas the world over each with their own preference.
A plain flat face with no grooves or any other design on the face works just fine. Keep in mind that a vast array of variants help the sales of what is a fairly simple device when all is said and done. The pressure you exert on the tamper doesn’t matter very much. Tamping won’t fix poor distribution and you can expect channelling if your distribution of the grinds has been poor. A key step is to make sure you are holding your portafilter level; this can take a bit of practice if you have a single spout on the portafilter and it is free to rock around in all directions. Then taking care to keep the tamper vertical, again that takes practice, press down and twist 45 degrees clockwise then 45 degrees counter-clockwise twice, in one continuous movement. Done.
8. For an electric pump machine with a heat exchanger design you will need to execute what is known as a ‘cooling flush’. As a very rough rule of thumb the water that initially comes from the group will be steaming, indicating it is too hot for espresso. After a few seconds the water coming out of the group no longer be steaming, indicating that the water is now cool enough for espresso. Attach the portafilter and get that pump running. Count off 25 seconds with the second hand of your watch from the moment the espresso first leave the bottom lip of the portafilter spout. As you stop the pump at 25 seconds remove the cup at the same time so the nasty foamy dribbly stuff that leaves the machine when you turn the pump off doesn’t enter your cup.
9. Reading the crema. Once you are familiar with the coffee you are using you should be able to accurately tell whether it is any good without tasting it just from the appearance of the espresso. tbc. that’s enough for xmas day.