Understand pre-infusion to take your espresso brewing to the next level
Jan 01, 2023
Pre-infusion is the process of carefully soaking the ground coffee puck in the portafilter before applying the full desired brewing pressure. The goal is to ensure that water evenly penetrates through 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 a espresso shot with pre-infusion compared to a espresso shot pulled without it, we notice significantly fewer cases of channeling - this is when water finds a path of low resistance and flows through it. This benefit is equally useful for new home baristas as it is for professional baristas. About if you have just started, it helps to have something that evens out any inconsistencies in the distribution of coffee in your portafilter. Even when you have spent years as barista, there is no reason not to use a technique that helps ensure you get a consistent extraction every time.
You find pre-infusion in its simplest form in machines with the classic E61 group head design, like our Profitec Pro 700. By partially lifting the brew lever, the path between the machine's water intake and the group head is opened - but the important thing here is that the pump does not start. This allows the passive line pressure of the water in the water line to push water from the boiler to the coffee puck at the group head. This line pressure is significantly lower than the 9 bars that the pump will apply, evenly and carefully saturating the puck. Most baristas will apply pre-infusion for somewhere between 2 and 8 seconds before they fully lift the lever and start the pump.
This method only works for directly plumbed machines. Espresso machines with internal fresh water tanks do not have the benefit 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 begin pushing water. Some of that water will take the path down the dead end and push against the piston, which relieves some of the pump's pressure from the coffee puck. When the pre-infusion time ends, the dead end is sealed and full pressure is then directed against the pump. Even About the method here is very different, the end result is the same cautious pre-infusion that you would get with a directly plumbed machine.
Manual flair espresso brewers have the advantage that you have full control over the brewing, 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 brewer is Flair 58 and Flair Pro 2 , which both have high quality and provide fantastic espresso shots. 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 techniques provide even more control over the water flow rate and pressure during brewing, which can help achieve even better results and unique flavors. About if you want to take your espresso brewing to the next level and experiment with different flavors, we recommend considering upgrading to a flow profiling machine or purchasing a flow profiling upgrade kit. These are compatible with all Profitec espresso machines with E61 group heads and can provide you with the precision and control you need to reach new heights in your espresso brewing.