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By: James Fairweather 07 August 2020
Nobody’s perfect right… we all make mistakes. And we don’t always have a friendly, helping hand to direct us away from these inaccuracies and onto the path of perfection. Super Sears is here to save the day once more! Clad in lycra (if you’re lucky) and pulling error-free espresso until the cow’s come home, Ol is here to help. Using his experience as an authorised SCA Barista Trainer he has identified the most common mistakes made by people at their espresso machine and provided tips on how to rectify them relatively easily. Here we go…
NOT USING ENOUGH COFFEE – Ignore old school Italian style espresso recipes of 7g singles and 14g doubles. This was the go-to dose back in the day but preference for increased coffee flavour has lead to a more modern standard of 16-18g double shots. This is due to the growth of the specialty coffee industry and increased access to super tasty, high quality coffees. There is no longer a need to limit dose in order to hide negative roasty flavours that were (and in some cases still are) typical of lower quality, darker roasted coffees. It is also worth noting that not a lot of machines are built to be at their best at 14g, yet another indicator that old recipes are becoming irrelevant and significantly out-dated. For reference, in today’s Specialty coffee market, 17-18g double espressos are now made as the standard dose.
INCREASING DOSE IN AN ATTEMPT TO CORRECT YOUR RECIPE – People have a tendency to think that by putting more coffee in a basket, they’ll slow down the speed of the espresso pouring from their machine. Although true, this ‘shortcut’ is not a recommended solution to create a longer brewing time and increase more flavour. It is also unnecessarily wasteful for home baristas whose coffee comes at more of a premium than wholesale customers. Especially when you can eek out a lot more from good quality coffee and have the bonus of going through your coffee slower, saving money and preventing wastage. In addition, an overloaded basket can cause technical problems for home espresso equipment of a lower build quality over time due to unnecessary pressure build-up.
USING PRE-GROUND COFFEE FOR ESPRESSO – Historically, espresso is a drink that is made bespoke to order in a café setting. This comes with the requirement of a decent grinder. DIALLING IN a coffee is an extremely complicated process, with grind settings subject to change for a variety of reasons. It may be convenient to pop shop-bought ground coffee into your portafilter but this comes at a price when it comes to quality. The resulting espresso can leave you with stale flavours, less flavour over all and little to no pleasant aroma. It can also make following an espresso recipe increasingly difficult, making it harder to control the flow rate of your espresso, which in turn negatively impacts extraction. Most ground espresso found in the supermarket is what we call an ‘omni-grind’ and has been ground in a way to try and cater for a number of brew methods. If you have read our previous blog post on THE IMPORTANCE OF GRIND SIZE then you’ll be aware of the impact your choice of grind setting has on extraction and the end flavour of your coffee. Grind should not be treated as a one-size fits all approach due to the fact that espresso machines and coffees have inherent differences as well as different needs.
USING A GRIND SETTING THAT IS TOO COARSE – Grinding too coarse, will result in a watery, weak or sour espresso. With a smaller surface area and more space between grinds, water under pressure will flow through coffee in the basket very quickly. This means that espresso can end up quite thin and underwhelming.
USING A GRIND SETTING THAT IS TOO FINE – Grinding fine is not commonly thought of as a mistake due to the increase of a coffee’s surface area and the ability to extract more flavour from the grinds over the same amount of time. However, too much flavour can be detrimental as not all flavour compounds are palatable. For instance, you can ruin a beautifully sweet specialty coffee by grinding too fine and ending up with a disappointing bitter shot of espresso. Not only can a fine grind be harmful to the flavour and strength of your coffee, it can also damage your machine as mentioned earlier. Even commercial machines struggle with espresso that has been ground too finely, leading to pressure problems, slow downs and damage to valves and mechanical parts.
To avoid the two extremes of grind size listed above you should aim to have all liquid espresso extracted into your receptacle of choice at around the 25-30 sec mark. This is assuming that you are using the ‘new modern coffee shop standard’ of between 16-18g of dry coffee at a brew ratio of 1:2. Please be aware that this is still a guideline and ideals will 100% change from coffee to coffee and depending on your equipment.
NOT DISTRIBUTING COFFEE EFFECTIVELY – Ultimately leading to channelling. This is an often unknown yet essential part of making great espresso. Most home baristas will never be told how important this step is. This involves levelling and settling coffee grinds evenly in the espresso basket.
You don’t need a fancy distribution tool to achieve this. Simply tap side to side with the palm of your hand and settle with a gentle tap on a work surface. Water always finds the path of least resistance so by following these steps you will prevent some of the channelling which can result in poorly/unevenly brewed espresso.
FAILING TO TAMP YOUR COFFEE LEVEL – Leaves you with a similar problem to poor distribution in that water will again find the thinnest/weakest spots in the basket to pass through. By not tamping level you are unknowingly compressing coffee more densely in one area than another and leaving at least one area shallower in depth. If one side of your coffee bed is lower you will find that gravity takes all water to that area, exploiting the difference between the sides. In short, this means you can under-brew some areas of coffee and over-brew others in the same espresso.
TAMPING TOO HARD – Similarly to grinding too finely, hard tamping is a strange and unnecessary way of attempting to slow down the brewing time/extraction of your espresso. As we mentioned before this should be addressed before coffee even enter the basket and controlled by choosing the right grind.
TAMPING TOO SOFT (anything less than 5kg worth of pressure) – will leave your coffee insufficiently compressed. Water will find gaps in the poorly compressed coffee and expand the grinds immediately. This can cause channelling and result in water passing through your coffee too quickly, without taking enough flavour with it.
NOT CREATING THE RIGHT STRENGTH IN YOUR ESPRESSO – Contrary to popular belief, strength is not a number on a bag, an expression of roast level or caffeine content. It is simply a matter of dilution. ie. “diluting” the shot of coffee you are making correctly to your taste. Great espresso recipes with high quality coffees can vary but most utilise strength as a key component to maximise your experience of coffee flavour, avoiding sharpness or insipidness. A good rule of thumb is to work to a 1:2 coffee to water ratio where the liquid you end up with is roughly double the weight of ground coffee that you started with. So if you use 17g dry, end with 34g wet. You can then play around with this ratio to find an espresso that suits your palette.
Have you struggled with/encountered any of the issues above whilst at the helm of your espresso machine at home? If you enjoyed this blog and would like to follow it up with an in-depth (not quite hands-on unfortunately – thanks Covid) session with our super friendly and knowledgable barista trainer Ollie, then our brand spanking new VIRTUAL HOME BARISTA COURSE is now live and waiting for you! 👈🏼 Click on the link to find out more about this great opportunity to learn espresso theory/practice from the comfort of your own home, in a course that is designed to help you get the most from your own espresso setup. Plus, who doesn’t want to hang out with this hero for 3 hours…?
Learn about our brand new online coffee course and training.