Coffee is a big part of my life, I love the process of making coffee as much as I enjoy the final product. For me it is a ritual; firing up the espresso machine, weighing out the beans, setting the grind, possibly throwing away the first couple of shots until I get the shot that I am after.
My journey began with a domestic Kambrook espresso machine that my wife bought me. Even with its limitations I learned how to pull some amazing shots. What I discovered is that although equipment is important, the person operating the machine has the largest influence on the final product. That being said we cannot discount the evolutionary design of the espresso machine.
Before the espresso machine was around filter coffee ruled the world. Any civilisation with access to coffee found a way to grind it and soak it in water. Filter coffee was made in bulk and poured out as people wanted.
The espresso machine changed all that. In the late 1800’s some clever Italians invented a steam powered single boiler machine that used steam pressure to push hot water through the ground coffee. This design was improved on in the 1940’s by the addition of pistons that pushed the water through the coffee at a higher pressure. Later in 1961 the first electrical motor driven pump machine was designed. Since then this design has remained the most common.
So why all this fuss just for a cup of coffee?
An espresso in essence is between 7 and 10g of ground coffee that has had about 9 bars of water pressing on it for about 30 seconds delivering a 25-30ml shot of espresso. These are not hard and fast rules but traditionally they are the norm. By designing a machine that forced the water through the coffee, three things were achieved.
1) More aromas are released because the coffee is ground finer to combat the high water pressure.
2) With more surface area(finer grind) being exposed to water you get more flavour being extracted out of the coffee
3) With the increase in pressure the oils that were previously insoluble in the coffee begin to emulsifying creating crema.
So next time you pass an espresso machine, show some respect! These machines created a whole new dimension to your coffee drinking experience.
Do you have a question about coffee equipment or a how-to that you would like Craig to unpack next? Let's hear it then!