Understand pre-infusion to take your espresso brewing to the next level

Pre-infusion is the process of gently soaking the ground coffee grounds in the portafilter before applying the full desired brew pressure. The goal is to ensure that water evenly penetrates the brew head to ensure that the entire coffee puck has the same amount of water flowing through it when extraction begins. In practice this works very well. When we have tested one espresso shot with pre-infusion compared to one espresso shot pulled without, we notice significantly fewer cases of channeling - that's when water finds a path of low resistance and flows through it. This benefit is just as useful for new home baristas as it is for professional baristas. If you're just starting out, it helps to have something to smooth out any inconsistencies in the distribution of the coffee in your portafilter. Even when you have spent years as barista there's no reason not to use a technique that helps ensure you get a consistent extraction every time.

You'll find pre-infusion in its simplest form in machines with the classic E61 group head design, like ours Profitec Pro 700. By lifting the bridge control partially opens the path between the machine's water intake and the group head - but the important thing here is that the pump does not start. This allows the passive line pressure of the water in the water hose to drive water from the boiler to the coffee puck at the group head. This line pressure is significantly lower than the 9 bar the pump will apply, evenly and gently saturating the puck. Most baristas will apply pre-infusion for anywhere between 2 and 8 seconds before fully lifting the lever and starting the pump.

That method only works for directly connected machines. Espresso machines with an internal fresh water tank do not have the advantage of line pressure and therefore must use different methods to achieve pre-infusion. Take for example Profitec Pro 400, one of the few espresso machines with an internal water tank that has built-in pre-infusion. It uses a specially designed chamber with a piston and spring that connects as a dead-end to the path between the boiler and the group head. When you start your shot, the path between the boiler and the group head opens and the pump starts to start driving water. Some of that water will make its way down the dead end and push against the piston, breaking off some of the pump's pressure from the coffee puck. When the pre-infusion time ends, the dead end is closed and full pressure is then directed to the pump. Although the method here is very different, the end result is the same gentle pre-infusion that you would get with a direct-connected machine.

Manual flair espresso machines have the advantage that you have full control over the brewing process, including pre-infusion. With such a brewer, you can easily experiment with different techniques and get exactly the results you desire. A recommended manual flair espresso maker is Flair 58 and Flair Pro 2, both of which are high quality and provide fantastic espresso shot. With a manual flair espresso machine, you can achieve the ultimate brewing experience and create unique flavor combinations.

Beyond pre-infusion lies a world of complexity and experimentation. Things like "flow profiling" or "pressure profiling" can be seen as the next step in the evolution of pre-infusion. These technologies provide even more control over water flow rate and pressure during brewing, which can help achieve even better results and unique flavors. If you want to take your espresso brewing to the next level and experiment with different flavors, we recommend that you consider upgrading to a flow profiling machine or purchasing a flow profiling upgrade kit. These are compatible with all Profitec espresso machines with E61 group head and can give you the precision and control you need to reach new heights in your espresso brewing.