Espresso is a short shot of concentrated coffee, water under pressure has been forced through the coffee & stopped once all the goodness is out. A bench mark for a well made espresso is 20 to 30 seconds from pressing the button to extract 20 to 30ml but when we use a speciality coffee blend* (Oh by the way, why we more often than not use a ‘Blend’ of coffees instead of one single coffee through an espresso machine is because a single origin may taste bland or unbalanced in the process of forcing everything out of it in a short time under pressure. This is why we make a recipe to create interest & a well balanced tasty espresso, a single origin is better used in brew methods such as cafetieres, filters or pour overs, where the extraction takes longer & is more gentle so to bring out those subtle delicate flavours.) * sorry… so when we use a speciality coffee ‘Blend’ for our espresso machine we don’t want to over roast (over cook) them, as we want to taste the characteristics of the beautiful coffee of where it’s from. The only problem with light roasts through the espresso machine is a light roast is less of a powerful flavour & is more light, fruity & acidic (The more thats roasted the more the acidity is roasted out. more acidity can be a sign of a speciality coffee). Forced through the espresso machine can make quite a sharp, flat bodied coffee, by changing things such as the extraction time & length of drink the espresso can then be made to be more full-bodied & keep the qualities of a traditional espresso. I may give an Espresso Brew Formula EBF, with some of my espresso blends which is how I recommend that particular coffee to be brewed.
The Coffee Refractometer
The best way & easiest way I can explain a Refractometer is it is a piece of equipment that reflects light through the liquid (in this case coffee) & shows you how many Total Dissolved Solids TDS are in the solution giving a TDS reading. Coffee can dissolve a maximum of 33% but we only want to extract enough good flavour, so the SCAE Speciality Coffee Association of Europe ‘gold cup standards’ says the perfect extraction is between 18 & 22% under 18% being under extracted & over 22% over-extracted. The Refractometer allows you to measure this along side the mojo to go app… allowing you to change factors to make the coffee taste it’s best, so by changing the grind size, water temperature or hardness/softness of the water or quantity of coffee to water?
I passed my brewmasters course a few years ago which was a couple of days training in Chelmsford & then I became an AST Authorized SCAE Trainer to be able to professionally train people on this.
The coffee Refractometer also measures other extraction methods – so just to show you here is one I did this morning with ‘Bec’s Coffee Blend coffee’ – El Salvador Monte Sion & Costa Rica through my Aeropress.
As you can see my coffee from this morning was right in range at 19.93%. It did taste lovely!!
I am sure I will do many more posts on this but I hope you have enjoyed reading my basic insight for now. Until next week… x
