FEATURE: Coffee brewing and consistency
What’s Your Baseline?
Good coffee is about understanding and controlling the variables – or at least the important ones. Regardless of your preferred brew method knowing your start point or standard settings gives you an important baseline to change one or more variables to improve what’s in your cup. If you don’t know where you started from you may change something and possibly make the final cup better but it is highly unlikely you will be able to repeat it the next time you brew. As one of my manufacturing gurus once said, “Without standards there is no improvement.”
Variables, what variables?
If we wanted to list all the variables that impact what ends up in our cup it would run into the hundreds at least. From ambient temperature, water temperature, water type, grind settings, extraction time the list goes on and on. There are so many variables that it is critical to choose the most important ones to focus on.
Variables can be divided into two main categories, the ones we can control and the ones we can’t. With this in mind the first variables to stop worrying about are those we have no control over e.g. how green coffee is stored before it is roasted. We just need to trust the roaster on that one!
Variables we can control are things such as grind setting (I hope you’ve read the previous article on the importance of grinding your own coffee?) and brew or extraction time for example. This still leaves many variables that we can easily get preoccupied with.
Which variables do I need to think about?
Narrowing down our controls is the next and logically we can list them in order of importance before finally selecting the vital few – the ones that we can clearly detect have an impact on the flavour of our final brew in the cup. Personally I break these down into Coffee Variables, Equipment Variables and Brew Process Variables. My key variables list is below.
Optimum time to brew from roast date (good roasters will provide this information)
Kettle (or pourover vessel)
Espresso machine maintenance intervals
Finished brew weight
Grind setting (particle size)
Pouring technique (drip coffee methods, V60, Kalitawave, Chemex...)
Pressure profile (some espresso machines)
Standing time (time between end of brewing to drinking)
Once happy with the variables you can easily control and have the biggest impact on flavour, I create my baseline standard for each different brew method I use whether I’m making espresso based drinks or any of the various filter brew methods. I have a preferred or starting brew ratio for each method, I control grind setting, pre infusion time, extraction time then if I want to influence the flavour I may choose to change one or more of these key variables. Although to understand the difference changing some variables will make, I always change just one at a time until I understand the result.
The ones I change most often for different coffees are grind particle size, water temperature, brew ratio and extraction time. By having this start point or Brew Standard it allows me to easily return to where I started if I find myself meddling too much and lose sight of where I’ve ended up!
Listed below are a couple of my basic Brew Standards, one for espresso I use on my trusty La Pavoni Professional and one for Hario V60 01 but don’t necessarily use mine, have fun and find your own!
Espresso (for La Pavoni Professional)
17g of coffee to 34g yield in the cup – 1:2 yield target in 25” to 30” extraction time
17g coffee in the double basket (grinder dialled in at baseline)
Boiler up to pressure (0.8 – 1.0 bar)
Flush the grouphead
Start the timer (40s countdown)
Slow lift lever (to avoid disturbing coffee puck)
8 seconds preinfusion when grouphead full of water
3 Short pulls to remove any air
18 seconds begin pull (constant pressure throughout)
Weigh yield which should be 34g to give a standard 1:2 double espresso shot
Based on the outcome I will decide if and what variables to adjust. Generally the first setting will normally be grind setting to achieve extraction time parameters.
Hario V60 01 Filter
15g of coffee to 250g yield in the cup – 1:16.6 yield target extraction time 2’50” – 3’20”
Kettle brewed to 95F and held (Brewista Temperature Control Pouring Kettle)
Wet filter and warm cup
Weigh and hand grind 15g of coffee (standard grind setting 25 clicks Comandante C40)
Add 15g ground coffee to filter
Start brew timer and begin pour
Add 30g water and stop pour to begin bloom (preinfusion)
At 40 seconds continue pour in 50g pulses
Stop pour at 250g yield (the cup will be full also!)
Total brew time should be not more than 3’20” and not less than 2’50” (extraction time)
Leave to stand for 60 seconds
Based on the outcome I would normally change either the weight of ground coffee and therefore brew ratio or if outside time parameters I would change the grind setting first to maintain the target extraction time.