In this section of the course, you will learn a lot about the step by step process of producing the finest espresso possible. This means you will learn how to properly measure and distribute the perfect dose of coffee, how to calibrate a coffee grinder, proper tamping techniques, and perfect extraction.
Techniques of the Perfect Shot
The four main techniques of a shot are:
- Dose / Distribution
- Grind Adjustment
- Pour / Extraction
Dose & Distribution
The dose is the amount of ground coffee used to brew espresso.
The proper dose for a shot should be between 14 and 16 grams.
Be sure the distribution of your dose of coffee is done properly and consistently leveling your coffee straight across the surface and filling all gaps.
Adjusting the grind is controlling the particle size of ground coffee, and is one of the key factors in Extraction Time.
The perfect Extraction time is 24 Seconds but the acceptable range is 22 to 26 seconds. If your shot time is slower or faster than that, you need to adjust your grind.
Imagine you have a bucket of rocks and a bucket of sand, both with holes in the bottom. If you poured water over the top, the water would run faster through the rocks than the sand. Think of the rocks as more coarsely ground coffee (larger pieces resulting in a faster shot) and the sand as more finely ground coffee (smaller pieces resulting in a slower shot).
Adjusting the grind finer will slow down the pour.
Adjusting the grind coarser will speed up the pour.
Your grinding burrs are two metal cylinders that are flat on one side, have blades on the other, and a hole in the center. They are both identical and one is attached to the adjustment collar (which allows you to make your grind finer or courser) while the other is attached to your motor. When you turn your grinder on, the beans fall through the center, are ground, and come out into your dosing chamber.
When you adjust your grind, you are either pulling the burrs further apart from each other to make it more coarse, or pushing them closer together, making your grind finer.
The purpose of tamping is to compress your dose of coffee, and give you a flat surface for extraction.
The tamp is the tool used to level and compress the coffee in the portafilter. The process is called tamping.
Pour / Extraction
The pour is the term we use to describe the espresso extraction itself, as it literally pours from the grouphead into the shot glasses. The espresso shot should pour steadily and remain golden in color, with just a little blonding at the end.
As long as the other factors in the shot are correct (dose, grind adjustment, tamp, and water volume) the perfect extraction time will take 24 seconds.