Espresso Machine Comparison: Pre-Infusion
Pre-infusion gently saturates coffee grounds before extraction to minimize channeling and improve flavor, with implementation varying from manual E61 levers to automated presets to full pressure profiling control.
- Pre-infusion saturates coffee grounds before full pressure extraction, reducing channeling and improving shot consistency across all espresso machine types
- E61 machines use a manual lever at the halfway point for traditional pre-infusion and require plumbing for proper line pressure
- Compact machines like Lelit Elizabeth and Victoria use electronically controlled solenoid valves with preset pre-infusion times of a few seconds
- Advanced machines with flow control (La Marzocco GS3 MP, Lelit Bianca) allow manual pressure profiling for customizable pre-infusion at 4-5 bars before ramping to 9 bars
"What is pre-infusion?" is a commonly answered question. How it can vary from machine to machine is a bit more complicated. Today we’ll dive into specifics and compare pre-infusion from a few of our most popular machines.
If your machine features pre-infusion, the overall capabilities and workflow might look and feel a bit different depending on your machine. If you’re still searching for your dream machine, we’re here to be your guide and help you find which machine and workflow sound perfect for your morning routine.
Ultimately, the goal with pre-infusion is the same from machine to machine. But if you’re unfamiliar- pre-infusion refers to the gentle saturation of ground coffee within the portafilter before ramping up the pressure inside the group head. This initial soak settles the coffee puck, which minimizes channeling and will give your shot the best chance at a perfectly even extraction for a rich, full-bodied flavor.
Today we’ll review a few different machine styles to understand how pre-infusion works within their specific class of machines. With a grasp on the technical components, pre-infusion will be something you can keep in your espresso toolkit to perfect your shots at home.
First, let’s take a look at our most popular and very traditional machine style — a directly plumbed espresso machine with an E61 group head.
With any E61, the halfway point between the lever full engaged and entirely off is where pre-infusion will occur. With the brew lever halfway opened, the top brew valve inside the group head opens, allowing water to begin filling the chamber just before the lever hits the micro switch on the front of the machine to engage the pump to start your shot. The machine needs to be plumbed in with this style of group head for a true pre-infusion since there’s not much back pressure coming from just the brew boiler alone. With a standard E61, pressure for pre-infusion is not variable or easily changed. The flow is consistent and infinite thanks to the line pressure behind your machine at its water source. We’ll talk about modified E61’s with flow control a bit later. Overall, if a tactile manual workflow sounds intriguing to you, a traditional E61 group head is undoubtedly a reliable route to achieve pre-infusion.
Next, we have these compact vibratory pump machines that only run off their own internal reservoir — machines such as the Lelit Victoria and Lelit Elizabeth, which are affordable and compact. We’ll also include the LUCCA A53 Mini in this comparison, with the optional pre-infusion chamber. In this case, they all operate in a very similar manner.
These machines use an electronically controlled three-way solenoid valve to start and stop water flow to their group head. They also feature an additional chamber or separate pipe reserved for a small amount of water for pre-infusion specifically. With this digital component, pre-infusion is preset with a specific time or volume allotted. This function is different compared to the other styles since you are limited to only a few seconds maximum, but that’s typically all you will need to saturate the grounds thoroughly. If you’re someone who craves precision but prefers to let the machine do all the hard work, a compact machine of this style is an excellent option.
Lastly, the machine style for those who want it all - machines with flow control or pressure profiling used to perform a manual pre-infusion. In recent years, additions have been added to E61 machines to control their group head’s flow rate, similar to high-end commercial machines.
Our favorite machines with variable flow profiles are the La Marzocco GS3 MP and the wildly popular Lelit Bianca, both phenomenal machines with endless amounts of control and versatility. With their manual paddles, you’re able to adjust the flow at the group head to simulate line pressure with a gentle ramp-up in brew pressure. Our go-to with this machine style is typically a 3-4 seconds pre-infusion at 4-5 bars of pressure, then flipping the paddle to the open up to 9 bars to finish our shot. But again, with flow control, the options are endless. If you enjoy a hands-on experience and find experimenting and tinkering with details exciting - you’ll love this workflow.
Whether you’re a novice or experienced barista, a little pre-infusion can easily benefit your daily espresso routine. A gentle saturation with any machine style will help keep your shots consistent and will bring out that delicious full-bodied, rich flavor we’re all trying to achieve. For some, a set it and forget it option works best. Others want options and versatility.
Now it’s up to you to decide what will suit your needs! But of course, our team here at Clive is always here to answer any of your questions and be your guide for all things espresso.
Frequently Asked Questions
What is pre-infusion and why does it matter for espresso?
Pre-infusion is the gentle saturation of ground coffee before applying full brewing pressure. It settles the coffee puck, minimizes channeling (uneven water flow), and gives your shot the best chance at even extraction for rich, full-bodied flavor. This technique works across all espresso machine types to improve shot consistency.
How does pre-infusion work on E61 espresso machines?
On traditional E61 machines, pre-infusion occurs when you engage the brew lever halfway. This opens the top brew valve, allowing water to fill the chamber before the pump engages for full extraction. E61 machines need to be plumbed in for true pre-infusion since line pressure is required, and the flow is consistent and non-adjustable unless you have a flow control modification.
Which espresso machines offer the most control over pre-infusion?
Machines with flow control or pressure profiling capability, like the La Marzocco GS3 MP and Lelit Bianca, offer the most control. Their manual paddles let you adjust flow rate and pressure in real-time, allowing you to perform custom pre-infusion (typically 3-4 seconds at 4-5 bars) before ramping to full 9-bar pressure for extraction.
Do compact espresso machines like the Lelit Victoria have pre-infusion?
Yes, compact vibratory pump machines like the Lelit Victoria, Lelit Elizabeth, and LUCCA A53 Mini feature automated pre-infusion using electronically controlled solenoid valves. These machines have a separate chamber reserved for pre-infusion water and use preset times (typically a few seconds) to saturate grounds before full extraction begins.