1. Proper Equipment Operation
Understanding the mechanics of how to operate your equipment and properly maintaining them will yield better and consistent results. This is much like going through drivers ed, learning how to operate the vehicle and regular inspections to ensure it keeps running properly. Knowing your equipment will also help you identify any problems down the road. For anyone pursuing consistency in their brewing technique consider adding there pieces of equipment to your wish list; A burr grinder, scale and water filtration.
2. Water Quality
There are two key ingredients to brewing coffee; coffee and water. Just as a chef in a restaurant would seek out quality ingredients for their menu it behooves us to treat our coffee preparation in the same manner. Have you gazed into your water kettle at home and notice a white-ish buildup on the interior? When one boils hard water from the tap, water with a high mineral content, as the water turns to vapor it leaves behind the mineral deposits in the kettle, coffee maker or the boiler of the espresso machine. Now imagine how the contents in the tap water would affect the taste of the brew. For example, if the water from the tap is high in mineral content or heavily treated with chemicals the water will not be able to extract the coffee goodness as well since it will already be loaded with other things. This typically means the resulting brew will be under extracted. On the other hand, using distilled or purified water will create a softer water content meaning it will want to absorb as much out of the coffee as possible, in other words over extraction. There is a delicate balance of water pH and alkalinity in water which creates an ideal environment for brewing. We can continue further down the rabbit hole on the subject of water quality but we’ll save the juicy stuff for another time.
Think of this as the recipe for making coffee. The appropriate coffee to water ratio will allow for an extraction which is within range of optimal flavor. Using too much coffee and not enough water will produce an under extracted cup whereas using too little coffee and a lot of water will yield an over extracted batch. This is where a scale will come into play for measuring out the ingredients. This develops recipe consistency and eliminates the guesswork. The standard window to work with is 1 part coffee to 14-17 parts water (1:14-17). I typically start with 1:15 as my ingredient ratio. Depending on variables like the roast, the brewing method and taste, I will adjust the amount of water necessary for what I am expecting as an end result.
4. Grind Matching
the grind size to the brewing method of choice will directly influence the timing of the extraction. Think of ground coffee as a bucket of rocks versus a bucket of sand. If the grind is too coarse, like a bucket of rocks, then the water is just going to pass right through the bed of coffee not allowing for the coffee goodness to extract. If the grind is too fine, like a bucket of sand, the increased exposed surface area of the coffee will just absorb the water not allowing it to pass through as quickly. The longer contact time coffee has with water the more it will extract. Depending on the method the particle size needs to be adjusted. In the case of French Press or Cold Brew methods, the coffee and water are sitting together over an extended period of time, thus a coarse grind would be sufficient. If one is working against gravity or the application of pressure extraction then you need to adjust to a finer grind to control the flow of water through coffee. Consistency of your grind will play a major factor as well. Investment in a good burr grinder not only will provide fresh ground coffee but also consistency of particle size.
Having a set extraction time as a fixed variable will help in troubleshooting how coarse of fine to grind. One can swiftly be overwhelmed with the multiple moving variable targets without establishing a time range which works. For pour over style brewing the timing range falls between 3-4 minutes to allow for optimal extraction. For espresso preparation the range is 20-30 seconds. If the extraction time falls outside of the ranges then a grind adjustment is in order. Keep in mind the bucket of rocks vs. bucket of sand analogy when observing the flow rate of your coffee extraction then make the adjustments accordingly.
This is another relatively fixed variable when it comes to brewing coffee. The ideal temperature range falls between 195° - 205° Fahrenheit. When water reaches boiling point, at 212°F, the speed at which coffee flavor moves through the grounds to the brewed state is increased due to the high temperature. This also results in a brew which is over extracted and bitter. A simple beverage thermometer will help determine when the water has cooled down to the acceptable range before incorporating the freshly ground coffee. When it comes to Cold Brew methods directions indicate use of room temperature water since the mixture sit over an extended period of time allowing the flavors to slowly be coaxed out. Heat still plays a vital part in brewing a cup with
7. Even Distribution
Water and gravity will work together to find the path of least resistance in a bed of coffee. If there are breaks, gaps, pockets, cracks or an uneven surface then the water will rush to those areas where passage will be easier. If the grinder does not produce a consistent grind particle size the water is sure to find the gaps to pass through quickly thus affecting the extraction. This is especially evident in preparing espresso. A simple motion of shaking your filter cone will help settle and level the bed of freshly ground coffee. The finer particles will work towards the bottom and in the spaces between any larger sizes. For French Press a simple act of stirring the coffee before letting it sit will ensure all the grind surfaces are contacting the water. Also take into consideration the pattern in which water is being poured over the bed of coffee. Faster more aggressive pours will agitate the bed of coffee creating those pockets for water to channel through quicker.
Ready? Set? Brew!
Now that the mind is swimming with variables, scientific and otherwise, take a step back and remember a key component in the final outcome is taste. When it comes to honing in on brewing coffee the individual perception of taste and personal preferences will factor into the expectations. Be patient in finding the recipe which tastes good to you. Make mistakes, learn from them and keep moving forward by adjusting the different variables. Part of the joy in making coffee is the magical moment when all the variables and the cosmos align providing in that particular moment the perfect cup of coffee.