Espresso shot: Volume vs weight- still confused

Coffee preparation techniques besides espresso like pourover.

#1: Post by rmachin »

OK sorry to flog a dead horse here, but I have reviewed other posts in this and other forums where the question is discussed, but I didn't see a clear answer so asking here so those with more experience than I have might help me out with some direction.

Received wisdom is 1:2 grams, so for a double shot 18g in, 36g out.
Received wisdom is also that a double shot should yield about 2 fl oz of liquid.

So clearly, these two are usually in conflict: 2fl oz is way (if not weigh) more than 36g.

My Breville Infuser comes programmed to produce an almost perfect 2fl oz volume for a double shot, so should I reprogram it to produce more like 1.2 fl oz to comply with the weight mandate, or not?

To produce a 1:2 ratio shot by weight I have to drastically reduce the shot time, or grind much finer and risk a sour pucker.

I've read advice to "always go with weight", but in that case I'd never reach a 2oz shot with any of the grinds I've tried. Any help? For a beginner, this seems a fundamental question that needs to be answered before all the other variables can be considered!

Thanks - Richard.

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#2: Post by MNate »

Yes, ignore volume as that will vary by how much air/crema gets in the shot. Weight will always be consistent though.

Also, an 18g dose really isn't a double so even there you should be aiming higher than 2oz.

So how to dial that in for you...

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#3: Post by MNate »

Yeah, the Breville's buttons are super easy to program. actually though you don't really want to program the yield until you've dialed in your shot so it's somewhere in ballpark for you- just run the shot manually and stop it at the desired 36g yield. Ignore the program buttons for awhile until you get the hang of it. Then when you start liking your shot you can program the button.

Taste and blonding are more important than time or weight. I'd pull a shot until it blondes, note the time it took and the weight of the yield, taste it and adjust. There are some handy charts in how to adjust that I really like.

There's tons of reading on home-barista about how to dial in a shot, but we'd certainly answer more of your questions! (And likely people better than me will be chiming in too.)

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#4: Post by Jake_G »

rmachin wrote:Received wisdom is 1:2 grams, so for a double shot 18g in, 36g out.
Received wisdom is also that a double shot should yield about 2 fl oz of liquid.

So clearly, these two are usually in conflict: 2fl oz is way (if not weigh) more than 36g.
Hey Richard,

Welcome to HB!

The short answer is that weight is what matters.

The long answer is that while 2oz of water weighs much more than 36g, 2oz of espresso is probably closer to 28-30g, and that's because of the air/CO2 engrained in the crema. The crema "fluffs up" the volume, and makes a small mass take up lots of space. Putting it another way, a freshly pulled shot of espresso has a density of about half that of room temperature water.

The other thing at play is that the 2oz rule comes from Italian standards for espresso, which are very clear that a double shot is 14g of coffee to make 2oz of liquid espresso. That 2oz weighs roughly 28g, thus an 18g double yielding 36g of beverage weight might produce about 70ml of liquid espresso, or nearly 2.4oz.

But remember that the volume is highly dependent on how gassy the beans are and how much volume the crema adds to the shot. You are way better off to go by mass...


- Jake
LMWDP #704

rmachin (original poster)

#5: Post by rmachin (original poster) »

Alright many thanks all this is helpful. An immediate rookie mistake I was making was comparing fl oz by shot cup volume using water, which I see is heavier by far than freshly infused espresso. OK - also, in trying to reach the 2oz I was waiting too long (even though 30 secs - another rule rookies cling to) - and teh shot was getting far too light. Yes, I had to google the diff between sour and bitter, and tasted shots early and are into extraction to get the diff!

SO key is to ignore the std shot volume, get the weight and color right in a ballpark timeframe, adjusting grind for that. I don't see the programming as that important, unless perhaps you could store a prog for each bean you're trying - which in the case of the Breville, you can't. So a post-it on the wall it is, for now.

Thanks all - any further advice of course very welcome.

-- Richard.


#6: Post by espressoren »

Accounting for cream is a good tip. Also, don't be afraid to adjust to 1:2.5, or even up to 1:3 on light roasts. You may end up closer to that 2oz water weight than you think. It's not that uncommon for me to pull 50g from a 20g puck.

When I started out I was so dead set on the 1:2 rule but when I relaxed and started dialing in to taste I found some beans are better at 1:2.2 or whatever.

I think with espresso traditionally being dark roasts the 1:2 (or sometimes less) makes sense, but when you get into medium and light roasts it takes adjustment to get the most out of the beans.

rmachin (original poster)

#7: Post by rmachin (original poster) »

Good info. I tried middle of the road Starbucks beans, a couple of more artisan local roasts, and then Illy vacuum packed to get some experience - I have a Sette 270 and it's surprising how much I needed to adjust the grind for each. Permission to experiment is important so thanks for that! I think the manufacturers talk about adjustable temps, pressures, volumes etc when that can lead to chaos for beginners. I did get the best taste results when stopping the shot a little early just as the color faded and that syrupy look went a little watery, even though sometimes the time was 23 or so. I did invest in a bottomless filter to help judge that. Experiments with longer times and too fine grinds I found can be almost poisonous!