Testing the Grind Size on Your Home Espresso Machine
While every espresso machine is different in terms of power, age, and maintenance habits, if you follow a few simple steps you will be taking great strides toward ensuring consistency in every shot.
Keep in mind that pulling a shot is essentially a chemistry-experiment-meets-Goldilocks exercise!
WHAT YOU'LL NEED
- a scale, ideally one sensitive enough to measure to the half-gram
- a timer/stopwatch—your mobile phone works well
- an Old Barracks Coffee Roastery sample, note the grind size
- the size of your portafilter, which you can Google with your machine make and model
For 51mm portafilters, like the Delonghi Dedica:
- measure 12g of ground coffee into the portafilter
- tamp, not too hard, not to soft
- place a cup beneath the portafilter on the tared scale
- brew, aiming to get 24g of espresso into the cup in 18-19 seconds
For 54mm portafilters, like the Sage Bambino:
- measure 15g of ground coffee into the portafilter
- tamp, not too hard, not to soft
- place a cup beneath the portafilter on the tared scale
- brew, aiming to get 30g of espresso into the cup in 22-23 seconds
ASSESSING THE PROCEDURE
- If the flow is too slow to obtain the specified volume in the specified time, the coffee is ground too fine (or your tamping is too hard).
- If the flow is so fast that the espresso seems to gurgle out of the portafilter and/or you get the specified volume too quickly, the coffee is ground too coarse (or your tamping is too light).
- There’s also the possibility that you have too much or too little in the portafilter, so if the grind sizes aren’t working, try increasing or reducing the amount in the portafilter.
Repeat this experiment with each different sample grind size, and let us know which works best for your machine.