Post By anst1ssa
Volumetrics help - do you need to dial it in or set and forget?
I've started helping out a church try to improve the quality of their coffee - basically, since I have a machine at home, I'm apparently an "expert"!
I've got a decent grip on dialling in a bean and shots using scales and a timer, but I've never used a commercial machine with volumetrics before.
I've been told that the volumetrics has been calibrated and already preset - next time I'm in I will weigh the water from each grouphead to see if each group is pouring the same.
Assuming that the volumetrics is okay and set to pour the correct amount of water, can I simply forget about it and just focus on dialling in the dose and extraction over the target time?
I also didn't take note of the brand and model of the machine the first time I went in (whoops).
Coffee is from Commonfolk and delivered weekly, so working with good fresh coffee, but I need to see if they supplied the machines and did the initial setup. If so I'm hoping that I can just focus more on getting consistency in dosing and dialling in the grinder rather than worrying if the machine as a whole is setup wrong.
It is wise to adjust the volumetric settings based on how much espresso you wish to extract from your dose.
You aim to dose (grind) 20 grams of coffee and extract 40 grams of espresso.
Without making any adjustments, weigh the espresso after extracting from the 20 gram dose, then adjust the number of pulses/amount of water via the volumetric settings on the machine to head towards your target extraction (of 40 grams out).
After you've achieved your desired shot volume, you can begin to dial in the grinder in order to determine how quickly the shot of 40 grams is poured. Speaking generally - you might aim to reach your 40 gram espresso in a shot time of 28-30 seconds.
If you're using the same coffee week in/week out, you can probably set your volumetrics up and then forget. I'd first check to see you're getting close to the same output from each group before relying on the volumetric settings on the machine.
That makes sense. Thanks!
What anst said is exactly right. And I can definitely reccomend weighing your shots as opposed to using mls because the crema changes over time depending on freshness. So if you measure with mls using beans 2 days old there will be a lot of crema and not much fluid (crema less dense than fluid). Then is you still have the same beans 2 weeks later all of a sudden what you thought was 40mls is actually 25mls. I normally try for 22gram dose 28-30dec extraction time for a yield if 55grams, this gives you 2 X 27.5 gram shots which will enable you to make 2 X espresso shots at the same time.