Hello again coffee enthusiast and espresso machine shoppers. In Part Two of the machine-types blog series, we will be going over the Semi-Automatic Espresso Machine. This type of machine strikes a comfortable compromise between user control and user convenience.
Beginning to Control the Variables
With a semi-auto, it is the machine itself, that starts to control the variables of espresso making. While this may not be what hard core coffee enthusiasts want to hear, keep in mind you still have plenty of variables that you can control to produce the shot of espresso you are looking for.
The semi-auto has an internal pump, which ensures consistent pressure for duration of the brew process. However you still control the amount of coffee used, the volume of water brewed through, as well as the grind and tamp variables that produce the nuances of the shot.
Semi Auto Features
There are also some semis that step up and offer to take other brewing variables off of your hands, using a number of methods. First the pressurized basket which basically alleviates you from having a perfect grind and tamp. The non-pressurized commercial basket allows a greater range of control of the shot. (For a more detailed explanation of the two, check out ‘How Do You Brew? Pressurized or Non-Pressurized?’, about the different types of filter baskets.)
Also, there are the ‘programmable semi-automatic’ espresso machines. These machines usually have one or two programmable buttons that lets you program the amount of water that is pulled through a shot. You activate the pump, pressing one of the programmed buttons, and the machine’s control board deactivates it. Examples of these types of machines include the Gaggia Espresso Dose and Pasquini Livia 90 Auto.
Lastly, the top end semi-autos are in a class of their own. We call them Prosumer machines. These machines are characterized by large heat exchange boilers, E61 group heads, and commercial/non-pressurized portafilters. Examples would be anything in the Expobar, Brasilia and Rocket Espresso lines. These machines are powerhouses that are for the demanding user. Once up to temperature, they provide instant steam, and hot water, and will even allow you to brew and steam simultaneously.
Other Features Offered – And Don’t Skimp on the Grinder
Semi-autos, are also the largest group of machines. There are available different classes, and have a number of features that are available, including: Thermoblock and volumetric boilers, single and double boiler, 3-way solenoid valves, ESE pod capability, and temperature control via Proportional Integral Differential, or PID.
The other thing to keep in mind is that the machine is only about half of the equation for producing a good shot. The grinder is an integral part of the brew process. As you go about choosing your grinder, don’t put 95% of your budget into the machine, keep it at about a 60/40 ratio. This rule of thumb is about right for most machine pairs. Your espresso machine and grinder are like your washer and dryer. If you buy a high-end front-load washer, you aren’t going to buy the door-buster special dryer. You’ll want to buy a dryer that can keep up with the washer; the same thing with grinders and semi-auto espresso machines.
What Does It All Add Up To?
So what does it all mean? In the end, it still comes down to how much control you want or need over the shot you pull. If you’re a coffee enthusiast and want to have a lot of control over your shot, then a semi-auto may be appropriate for you. If you prefer to get up in the morning, press a button, and have espresso dispensed into your cup, then you’ll want to check out my next blog: Super-Automatics.