My evaluation process for a home espresso machine is similar to how I test standard drip coffee makers. First, I wash and dry all removable parts and accessories. For most espresso machines, this includes the filter basket, metal portafilter inserts, water tank, and so on. Next, I run a brew cycle with just hot water to wash away any remaining material from the manufacturing process.
Most automatic espresso machines, aside from fancy super-automatic models, lack one built-in Coffee grinder And I prefer espresso machines with freshly ground coffee, not ground coffee, so I’m trying my own grinder: the Breville Smart Grinder Pro. I chose this conical grolder for two reasons. First, it is more calibrated for espresso than drip or other brewing styles. This means it produces a coffee bean that is pretty good. Second, its grind size is consistent throughout. Both factors are crucial to a proper espresso brewing process.
To pull shots, I start with the suggested method described in the product manual for a particular machine. Typically this covers the amount of coffee expected per shot, along with guidelines regarding coarseness. Likewise, I follow tamping instructions (light, medium, or hard tamp) when the manual provides them.
Whenever possible, I brew double shots of espresso for all of my test runs. I make sure I record the weight of the grounds I use as well as the weight of espresso for each shot I pull. This data, along with readings from a portable refractometer, allows two important percentages to be calculated: total dissolved solids and extraction percentage.
Exactly for any coffee brew, the ideal extraction percentage for espresso is between 18% and 22%. This will produce a balanced cup provided you perform an even and efficient extraction of coffee rushes from your plot (both flavor and caffeine).
Not many home espresso machines can brew quality shots. This was pulled from the Breville Barista Express.
If you over-extract, you risk extinguishing unpleasant flavors (bitterness) after the good. At the other end of the scale, under-extracted beers tend to have undeveloped flavors. These shots taste sour, weak and watery, without sugar and other caramelized organic chemicals.
Unlike a cup of drip coffee, barista espresso should be concentrated. Great drip typically has a TDS percentage of 1.3% or 1.4%, great espresso has a much higher percentage. The Breville Barista Express, for example, produced shots with TDS percentages as high as 12.4%.
The shots I pulled were balanced with an extraction of 18.6%. The test coffee beans I use are the same variety that I use for standard coffee machines – Costco Kirkland Colombian. It is a medium roast that is also suitable for brewing espresso.
Many espresso machines have steaming wands for frothing milk. The Bambino Bambino is particularly simple.
Finally, I try making milk foam using any coffee machine that is equipped with a steam wand. I capture the overall steam wand experience, whether the process is a snapshot, a tricky task, or somewhere in between.
You can use steamed milk to create espresso drinks like lattes and cappuccinos.
