Unlock better espresso: a guide to manual pre-infusion with the Profitec Go

The Profitec Go has earned its reputation as a powerhouse in the world of single-boiler espresso machines. It offers rapid heat-up times, PID temperature stability, and the build quality Profitec is known for. However, one feature it lacks out of the box is automated pre-infusion. While this might seem like a drawback, it’s actually an opportunity. By mastering a few simple manual techniques, you can gain a level of control over your extraction that rivals more expensive machines. This article will guide you through the why and how of manual pre-infusion on your Profitec Go, transforming a perceived limitation into one of your greatest assets for pulling consistently delicious, café-quality shots from your home setup.

Why pre-infusion matters for your Profitec Go

Before we dive into the techniques, it’s crucial to understand what pre-infusion is and why it’s so beneficial. Pre-infusion is the process of gently wetting the puck of coffee grounds at a very low pressure before applying the full nine bars of extraction pressure. Think of it as giving the coffee bed a moment to settle and prepare for the intense pressure to come.

The vibratory pump in the Profitec Go is powerful and ramps up to full pressure very quickly. Without intervention, this can hit a dry, unprepared puck of coffee like a hammer, sometimes fracturing it and creating tiny channels. These channels allow water to bypass the coffee grounds, leading to an uneven extraction that tastes both sour (under-extracted) and bitter (over-extracted) at the same time. This is a common issue known as channeling.

By manually pre-infusing, you achieve several key benefits:

Reduces channeling: Gently saturating the puck allows the coffee grounds to swell and expand, creating a more uniform and resistant bed. This helps ensure water flows evenly through the entire puck during the main extraction.
Improves consistency: A well-executed pre-infusion makes your puck prep more forgiving. Minor imperfections in your distribution or tamping are less likely to result in a disastrous, channeling shot.
Unlocks flavor clarity: An even extraction allows you to taste the full spectrum of flavors in your coffee beans. You can achieve sweeter, more complex, and balanced shots.
Allows for a finer grind: With channeling minimized, you can often grind your coffee finer than you normally would. This increases the surface area of the coffee, allowing for a higher extraction yield and richer flavors without choking the machine.

Essentially, manual pre-infusion gives you direct control over the most critical phase of the espresso shot, turning your Profitec Go into a more versatile and capable machine.

The pump-flick technique explained

The most common and effective method for manual pre-infusion on a machine like the Profitec Go is what many in the community call the “pump-flick” or “on-off” technique. It’s incredibly simple in principle but offers a deep well of variables to experiment with. The goal is to use the pump just long enough to wet the puck and then pause before the full extraction begins.

Here is a step-by-step guide to performing this technique:

Prepare your puck: Go through your normal routine of grinding, distributing with a WDT tool, and tamping your coffee. Lock the portafilter into the group head.
Start the pump: Place your cup on the scale and start your timer as you flick the brew switch on.
Watch the pressure: Keep a close eye on the machine’s pressure gauge. You are not letting it ramp up to the full 9-10 bars.
Stop the pump: As soon as the gauge reads about 2-4 bars of pressure, or when you see the very first drops of espresso begin to form on the bottom of your basket, flick the brew switch off. This initial “on” phase usually lasts only 3-5 seconds.
The soak phase: Now you wait. With the pump off, the residual pressure in the group head will slowly decline while the hot water saturates the puck. This is the pre-infusion soak. A typical soak time is between 5 and 10 seconds.
Begin extraction: After your desired soak time has passed, flick the brew switch back on to engage the pump at full pressure and complete the extraction as you normally would.

The beauty of this method lies in its adjustability. A shorter initial pump time is gentler on the puck, while a longer soak time can help extract more from lighter roasts. You must experiment to find the perfect combination for your specific coffee beans.

Dialing in your pre-infusion shots

Introducing pre-infusion into your workflow means you’ll likely need to adjust your other variables, primarily your grind size. Because pre-infusion makes your shots more resistant to channeling, it opens the door to grinding finer. This is where the magic happens.

Start with your current grind setting and apply the pump-flick technique. How does the shot behave? If it runs too fast, don’t just increase the dose. Your first move should be to grind finer. Make small, incremental adjustments until your shot time is back in the ideal range (typically 25-35 seconds for a traditional 1:2 ratio). You’ll notice that the resulting shot, even at the same ratio and time, tastes sweeter and more balanced than before.

Keeping a simple log can be incredibly helpful. Note the coffee, dose, initial pump time, soak time, total extraction time, yield, and most importantly, the taste. This will help you identify patterns and replicate your best results. Use the following table as a basic troubleshooting guide as you dial in.

Problem	Possible Cause	Potential Solution
Shot runs too quickly and tastes sour	Grind is too coarse; pre-infusion not long enough.	Grind finer. You can also try increasing the soak time by a few seconds.
Shot starts with channeling or spritzes	Puck prep issue or initial pressure is too aggressive.	Focus on even distribution (WDT). Try a shorter initial pump-on time (e.g., stop at 2 bar instead of 4).
Shot chokes the machine or tastes very bitter	Grind is too fine.	Grind coarser. This is the most direct solution.
Shot tastes good but a bit weak or thin	Under-extracted, possibly due to grind size.	Grind finer to increase extraction. Pre-infusion gives you the safety net to do this without channeling.

Beyond the basics: a note on hardware mods

While the pump-flick technique is a free and highly effective software solution, it’s worth noting that the enthusiast community has developed hardware modifications for similar machines. For the Profitec Go, the most relevant mod is changing the gicleur. The gicleur is a tiny, screw-like jet with a narrow opening that sits inside the group head and restricts water flow. The stock gicleur is designed for a quick ramp-up of pressure.

Some users swap this out for a gicleur with an even smaller opening (e.g., 0.5mm or 0.6mm). This physically slows down how fast water can fill the headspace above the puck, effectively creating a gentler, more automatic pre-infusion phase every time you pull a shot. This can make your workflow simpler, but it’s a permanent change to the machine’s behavior.

It is extremely important to note that making this kind of modification will almost certainly void your machine’s warranty. It’s a path for advanced users who are comfortable working on their equipment and understand the risks. For the vast majority of Profitec Go owners, the manual pump-flick technique offers all the control and benefits of pre-infusion without any of the risks or costs associated with hardware mods.

The Profitec Go is an incredibly capable machine, and its lack of built-in pre-infusion is far from a weakness. By embracing manual control, you engage more deeply with the espresso-making process and gain a powerful tool for improving your shots. We’ve explored the reasons why pre-infusion is so critical for reducing channeling and enhancing flavor, and detailed the simple yet effective “pump-flick” technique to achieve it. By adjusting your grind to complement this new variable, you can push your extractions further, achieving a level of sweetness and complexity that may have eluded you before. So don’t be afraid to experiment. Play with timings, grind finer, and taste everything. You have all the tools you need to pull exceptional espresso.