It is every home barista’s dream to pull the perfect shot of a single origin coffee through your home espresso machine or make a striking cup of a pour-over, indulging yourself with the beautiful flavours that are locked within the beans as they were patiently maturing inside the coffee fruit. Or you might just like to share a good cup of coffee with your loved ones and friends and also, perhaps, show off your fancy rosettas while at it. But is it as easy as it sounds? Or do you need a thousand hours of experience behind a machine at a café to master the skills to do so?
The pursuit for the perfect cup of coffee for a barista is an endless journey and it is virtually impossible to achieve it in reality! As baristas, we can only do our best to examine and evaluate the ingredient that we have in our hands and experiment with it to achieve a better tasting cup of coffee one after the other. It is this journey that makes the coffee tasting and drinking experience more exciting and meaningful as we begin to appreciate the variety and fragility that coffee presents.
There are many factors in coffee brewing that can dictate the outcome, from the roasted beans you selected to use down to the choice of cup you drink out from. We need to look at it in every possible way so that we can eventually satisfy our senses and make us feel awesome about it. Let’s start exploring.
There are two mains types of coffee brewing. One is to use pressure, ie passing water through coffee via an espresso machine, and the other is let the extraction occur naturally, ie water dripping through coffee via gravity usually through a paper filter. Regardless of which method you decide to use to brew, you will end up facing differently tasting coffees that result from countless combination of variables. There are 4 important variables that you need to become familiar with.
Knowing exactly how much coffee you are using is like matching the first button on your shirt so that the rest of the process goes according to plan. Varying the dose can affect the intensity of the flavours and also the rate of flow of water through the coffee. In the specialty coffee world, baristas, roasters and coffee producers (well in fact the whole world) uses an accurate scale to measure and record the weight of what they are trading. The higher the accuracy and the precision, the more confident we can be in what we are doing.
This term is frequently used by current generation of baristas to describe amount of the extracted coffee liquid, which was traditionally measured by volume in a shot glass. Because of the Crema’s inconsistency in its thickness (which is dependent on the roast profile and freshness of coffee used) and the inaccuracy of reading the actual volume, we are more inclined to refer to the term Yield. This can be accurately measure by using a set of drip-tray scale.
3. Brew Time
How long does your shot last? Measuring this in seconds using a timer would give you a clearer idea of how your coffee might taste. Brew time can be altered by changing the dose and also may depend on the tamp pressure but the change in grind size of coffee trumps them all. By changing the coarseness of the grind you can control the water flow through the coffee bed, changing the extraction of flavours eventually affecting the brew time.
4. Grind Size and Freshness
We always recommend that people have a grinder at home and purchase beans. This allows you to grind the coffee fresh to serve. Pre ground coffee starts to go stale in a matter of minutes (yes minutes!). This is why you always see the best baristas ‘grind to serve’. By using pre ground coffee that has started to oxidize (go stale) you will notice the shot length, yeld and most importantly taste will change dramatically. If you don’t have access to a grinder yet, keep the coffee away from oxygen, sunlight, and fluctuating temperatures (see our coffee storage story for more information). If you do have a grinder, become familiar with how to adjust the grind, and don’t be scared to make adjustments. It is not uncommon to make regular adjustments throughout the day due to changes in temperature and humidity.
Using an ideal water temperature is essential in making delicious cup of coffee. Although it is not restricted to a particular number, in general water temperature ranging from 85 degrees Celcius up to just below boiling point is used for brewing. A very high temperature may lead to an over-extraction of flavours and a lower temperature might lead to an under-extraction.
Examples of the use of extraction parameters.
Dose = 23.0 grams
Yield = 40 grams
Time = 35 seconds
Dose = 23.0 grams
Yield = 55 grams
Time = 25 seconds