Where I currently roast, there is a coffee shop attached with everything required to make amazing shots of espresso and exquisitely crafted milk drinks. I pull my shots every day on a beautiful handmade Synesso Espresso Machine (soon to jump into the prosumer espresso machine market!). Making my drinks at home on a plastic domestic espresso machine doesn’t tickle my fancy so to speak. Call me a coffee snob, but I don't want to wait for a brew boiler to adjust on a single-boiler espresso machine before I can steam my milk. I want a version of what's in a cafe but shrunk down and sized for my kitchen.

It's not just me; any home barista worth their weight wants the best gear for the job. So if the art of extracting the perfect espresso is your thing, and you are comfortable with a higher price range, then a prosumer espresso machine is perfect for you. They take the build quality along with professional and durable components from commercial machines and shrink them down to fit into your home or office.

As with any type of semi-automatic espresso machine, baristas grind, distribute, tamp, and control the timing of the extraction on these prosumer espresso machines. These prosumer espresso machines are almost always designed internally with either a heat-exchange boiler or a dual boiler. They are normally either brass, stainless steel, or copper boilers. In the case of the dual, or double boiler, one is set for the extraction and the other to create steam.

They are more expensive, but you get the quality of a commercial espresso machine that lasts for years and gives you ultimate control over your coffee's taste. In the world of the best prosumer espresso machines, there are distinct features that affect espresso quality and some that just deal with functionality like being able to run a water line directly by using rotary pumps as opposed to the vibratory, or vibration pumps that run off a water tank. The bulk of models categorized as prosumer espresso machines by most retailers will also have shot timers, pressure gauges that keep constant track of pump pressure, as well as water and steam temperature controlled by a PID system.

PID Temperature Controller

Internal boiler temperature is controlled by a thermostat or a PID system. PID stands for “proportional integral derivative.” This system uses an algorithm to maintain temperature stability within one degree of optimal at all times. Machines that use a conventional thermostat vary as much as 10 degrees when idle whereas a machine with PID digital temperature control keeps things right at the temperature you set.

A heat exchange system without a PID requires a second flush of the group head after sitting for over 20 minutes. Dual boiler machines, which we’ll cover shortly, don’t require this additional step. PID systems are controlled by a dial somewhere on the machine or via a digital display that often includes an extraction timer.

Digital displays are more convenient if you make your espresso shots with different coffee roasts. Each level of roasting requires a different extraction time to get the best flavor.

Heat Exchange Boilers in Prosumer Espresso Machines

A major difference between high-quality semi-automatic machines is their internal boiler types. Some offer a heat-exchange boiler system that simultaneously operates the steam wand and the extraction. It achieves this through a large boiler with two chambers. One is kept hot enough to produce steam. The other maintains a lower temperature and circulates through the group head to produce water for extraction.

Compared to a single boiler machine, generally thought of as a beginner machine, where you have to wait between using the steam wand and pulling an extraction, a heat exchange system ensures your milk is at the proper temperature when mixing drinks like lattes. This will still not be as stable as a dual boiler machine in the long run but depending on the machine, can still make very consistent drinks back to back. Some of the heat exchange machines give the internal boiler a wrap of insulation. This minor detail means even more stable and consistent temperatures for machines in the prosumer espresso machine category.

Dual-Boiler Prosumer Espresso Machines

Dual-boiler espresso machines are the standard for most commercial and prosumer espresso machines that don’t have a heat exchange system. A dual-boiler system, as the name suggests, has two separate internal boilers. One controls the steam power for the milk froth, and the other operates solely for the extraction.

This technology produces the most consistent temperatures. Each boiler has an independent PID controller system, one for extraction temperature and the other for the steam boiler. These set-ups almost always have a design that is made for dispensing hot water for Americanos or tea as well.

This means that if you want to run an extraction dose at a lower temperature, you don’t have to lower the steam temperature like you would in a heat exchange machine. They add a little bulk to the machine as compared to a heat exchange system but give more control over how you steam milk and your extraction temperatures.

Group Heads

The Appartamento from Rocket Espresso is what some consider a starting point for prosumer machines with its E61 group head but lacks the PID for temperature control.

Group heads in prosumer machines are a vital part of what dictates extraction temperature consistency. The two main types of brew group heads in the prosumer market are E61 and fully saturated.

E61 Group Head

Most prosumer espresso machines use an E61 group head created in 1961 by Ernesto Valente. It first appeared in the Faema E61 espresso machine and was named after a solar eclipse that occurred that same year. It is internally constructed of solid brass enclosed by stainless steel and accommodates a 58mm portafilter—the industry standard. The E61 is controlled by a pull lever that releases water through the group head. When it’s pulled completely open, it releases 9 bars of flow pressure.

Saturated Group Head

Some brands offer fully saturated group heads that provide even more control than an E61. They take temperature control to the next level in the prosumer espresso machine market. As the name dictates, the entire group head is submerged in water pumped directly from the boiler. One can think of the group head as an extension of the boiler itself. Its constant immersion ensures that no external factors create temperature variations. A saturated group head heats up faster than an E61, another advantage.

Pre-Infusion

An additional feature present in many prosumer machines is the ability to control the pre-infusion during extraction. Pre-infusion timing is important when using different coffee roasts and can help bring out flavors. Many prosumer machines adjust manually to determine the initial flow pressure from the group head to the portafilter basket to begin the extraction.

Some prosumer espresso machines come pre-programmed with multiple options to saturate the espresso puck. This allows for the best extraction before 9 bars of pressure are applied and can vary in both time and the amount of pressure for the pre-infusion process.

Some premium prosumer espresso machines also control post-infusion. This regulates the last few seconds of espresso extraction, the period when the less ideal characteristics of the coffee are pressed out. This is essential to balance out the intensity of the shot in a controlled manner.

Variations and Options

The beauty of high-end prosumer products is the wide range of options available. Some target performance, while others are simply aesthetic or just well-designed switches to make life easier. One feature to look out for on many of these machines is the ability to drain the drip tray. It may be minor, but it assures a clean working area with no fuss.

Steam wands also have subtle feature differences. All Rocket Espresso Machines come with an anti-burn steam arm. Some assume that simply not grabbing the steam arm with your bare hands during use is common sense. I don’t disagree, but the more important aspect of the feature is that milk won’t stick to the arm, which makes it easier to clean.

Most prosumer machines come with accompanying accessories such as a high-quality portafilter, stainless steel tamper and steaming pitcher, cleaning detergent, and a water testing kit. Single boiler espresso makers that are more entry-level ideas such as The Rancilio Silvia or Gaggia Classic Pro will come with plastic and lesser-quality accessories.

One thing to make certain not to skimp on when looking to purchase a quality machine is a proper grinder. Your run-of-the-mill blade coffee grinder will not cut it. Grinders matched with these machines will be able to make very fine adjustments to grind size. These will be step-less adjustments so there really is infinite control. The burr size on grinders in this range is normally at least 50mm and will go all the way over 80mm in some cases.

If you want to wake up and have the convenience of pushing a button for a morning cappuccino with no effort foam, then a super-automatic machine or something with the ease of use of a Nespresso might be the best espresso machine for you. If quality extractions of your favorite gourmet, custom-roasted coffee beans at home are essential, then a prosumer machine is ideal for you.

For help picking out a prosumer machine, talk to your Coffee & Espresso Expert!