Breville BES920 - Double shot time / volume
I have recently purchased a Breville BES920 plus the Breville Smart Grinder Pro. I have been using fresh CS Colombian beans and the double shot basket that came with the machine.
I've been at it for a few weeks trying to get the grind, dose, and tamp right so that I get:
1) First drops / liquid coming through into the cup in 10-12 seconds
2) About 30 mL of espresso in the cup after 30 seconds
3) The pressure on the dial sitting around 8.5 - 9.5 bar once the pre-extraction phase is finished
Our coffee is being consumed as flat white. Whilst it tastes OK (maybe 7-8 out of 10) I just can't help thinking that I'm missing something important and am after advice.
I have read that double shot volume should be 60 mL (and not 30 mL like I am aiming for currently) but that would mean a much coarser grind and / or much longer extraction time than what I am currently aiming for. If I grind coarser then liquid would also start coming through faster, maybe in 6-8 seconds.
If I've been getting it wrong, what volume / times are correct for a double shot basket?
I assume you're using the single wall (non-pressurised) double basket? Seeing the first drops at 7-8s isn't a bad thing, in fact I'd say it's more normal. How long does your preinfusion run for?
How many grams of ground coffee are you putting into the basket? That and the brew ratio that best suits the coffee and your personal taste will determine the amount you want to get out. I haven't used those beans so can't comment there. I tend to prefer shorter brew ratios (like 1:1.5 or slightly less) where typical espresso is 1:2. Just go by taste, try adjusting the grind to get 60ml out and see if you like it better. There is no hard and fast rule for what you should be doing, only guides to get you in the ballpark and from there adjust to taste. If you were getting 20ml out in 60s and it tasted the best to you and you'd tried it at 60ml in 30s then my advice would be to keep doing what tastes good.
Do you know how much your dose weighs? My coffee improved dramatically when I fixed my dose (turns out the scoop I was using was about 15g and not 18g). Worth weighing at least a few times to get a feel for how much that is. The brew ratios are also based on weight, not volume. I reckon if you up your dose and fix your grind to match that you'll end up with about the right volume you're looking for.
FWIW the coffee I'm currently drinking tastes pretty good at 18g in, 36g out over ~25-30s from first drop of coffee coming out.
Edit: I'm using a 920 with a HG One.
Thanks for the reply!
Yes, I have been using the single wall double shot basket. Pre-infusion runs for about 5-6 seconds, then the pressure increases and depending on what I've done with the beans (dose / grind / tamp) the first drops come out 4-6 seconds after that.
Regarding the dose, I have been using the Breville precision dose tool to make sure the volume of coffee is always the same (after tamping, you run the tool over the basket and it scrapes off any excess). I'll have to admit I've never weighed the dose. I will have a go at varying the dose volume in next few days and adjusting the grind to get an appropriate amount of liquid.
Thanks for the reply!
To date I have been using the Breville supplied precision dose tool, so have been concentrating on getting a fixed coffee volume. I will experiment with using a higher dose (ie. not using the dose tool) and coarser grind next time around and see how that goes.
I highly recommend weighing it out and not using the razor tool (I used to use it but gave up on it) at least a few times. Even if you just use regular 1g kitchen scales to get in the right ballpark. Also might be worthwhile weighing the amount of espresso you're getting too just to see what that's like.
Originally Posted by Marcuscurypko
Also there is some good talk about how to get the best out of the 920 in the owners thread: http://coffeesnobs.com.au/brewing-eq...thread-36.html