Espresso Myths

August 03, '21
In the coffee industry we are always learning. If you ever meet a barista who says they know it all they are either lying or they are kidding themselves; coffee is a complex and constantly evolving product that, even after hundreds of years, we still don’t fully understand. When it comes to Australia’s favourite brew method, espresso, there are a number of myths that we have always taken for Gospel. We thought it was about time to put a few of them to rest.

Tapping the side of the portafilter with the tamp

Have you ever seen a barista tapping the side of the portafilter after they tamp? This seems very technical and adds some noisy flair to their routine. Surely this must be a good thing? Think again. This technique originated as a result of the congregation of small amounts of grinds on the inner rim of the filter basket after compaction; the tapping of the portafilter is an effort to knock these particles back into the basket. After losing these by bashing the outside of the rim, the Barista would then have to re-compact the coffee as the knocking motion would have loosened, or even split, the ‘puck’ which would in turn create channelling (water bypassing the majority of the coffee). While the coffee is under pressure, there will always be a few grinds that end up becoming loose regardless of their position within the basket. The effect of these ‘loose particles’ on the final cup is negligible and (arguably) imperceptible to the drinker. The tapping of the PF is widely considered to be ineffective, time consuming , damaging to the portafilter and detrimental to the final cup. The practice has, nevertheless, survived over the years but is slowly being phased out as baristas become more aware of the thought processes behind it.

Blonding = over extraction

‘Blonding’ is the end stage of extraction in which an espresso appears very pale and begins to wiggle due to lack of resistance. This myth of ‘Blonding is bad’ began because of people’s general assumption that less colour = less flavour. The beginning of the extraction appears darker and emerges slowly. This dark reddish-brown stage is the most intense part of the espresso. As the shot continues it will become gradually lighter and speed up as the resistance from the (now saturated) coffee grounds eases up. Finally we reach the ‘blonding’ phase and the extraction is ended. It is important to note that each stage of extraction will contribute to the complexity of a WHOLE cup. As the hot water and pressure exert themselves on the ground coffee particles they begin to release their full flavour, first come the acids, then the sugars and finally the bitterness; the bitterness has always been strongly associated with the blonding stage. The key to understanding extraction is that each stage has something to contribute to the cup, in essence, they should be balancing each other out to create an overall pleasurable cup for the drinker; how much of each aspect and when to stop the extraction is entirely in the barista’s hands. A good way to understand, and by extension, develop your brew recipe, is by catching the beginning, middle and end of a shot and tasting them separately. This will allow you to determine what each stage contributes. Remember that every coffee is different and there is no ‘golden rule’ that will work every time. In summary: Too much or not enough blonding can be bad. We no longer judge coffee solely on visual extraction and ridged rules – TASTE is the objective. We should be constantly experimenting to extract coffee to its full potential.

Rinsing the portafilter after every shot

Don’t get me wrong; cleanliness is extremely important in espresso making. There are, however, situations in which too much cleaning can be detrimental to the overall process; rinsing your portafilter after every extraction can be one of them. If you are rinsing your portafilter with water after each shot to clean away the grinds and oils you may notice a few things starting to happen: The portaflter will tend to hold excess water for quite some time after the rinse, possibly leaking onto your grind station (dry area) leaving a sloppy mess that is harder to maintain (not something you want to deal with in a busy café). In addition, the process of rinsing is quite time consuming and to perform this routine after each shot is pulled will result in customers waiting longer for their coffee. Apart from convenience, the real issue on this topic is with extraction consistency. If grinds are placed in a basket that has water residue, a minor ‘pre-infusion’ will begin to occur essentially beginning the extraction before the portafilter is even placed in the group. With no way to control this variable from shot to shot, added variance in the extraction will occur, and result in an uneven, unpredictable and inconsistent cup. Our aim is consistency. Ideally, a quick wipe of the basket with a dry microfiber cloth or tea towel will achieve a more consistent and efficient result.

‘Burning’ coffee grounds

Have you ever noticed the temperature difference between a group head, portafilter and ground coffee? The group and portafilter are very hot; they may even burn your hand if you touch them! The coffee grinds – not so much; they generally will sit at room temperature. If the portafilter is locked into the group with fresh grinds inside each moment that passes will increase the grind’s exposure to intense heat. This could result in under extraction (due to channelling) as the particles expand and ‘cracks’ form around and through the compacted coffee. The result is a cup with an abundance of undesirable characteristics often mistaken for ‘burnt’ coffee. This is where the myth of ‘burning’ the coffee if you do not press ON straight away’ comes from. In truth, it is not ‘burning’ but it is changing the structure of the coffee rapidly! Consistent temperature + constant routine = consistent espresso. So often in this industry we are taught to do things a certain way because that is the way it’s always been done. Remember that it is always okay to ask that very simple but very important question, “why?” Happy brewing!