Bottomless portafilter = more volume

Want to talk espresso but not sure which forum? If so, this is the right one.
User avatar
AndyS

#1: Post by AndyS »

(split from Fiorenzato Bricoletta - A Pro's Perspective by moderator...)
malachi wrote:I decided to see what the crotchless would reveal about the two baskets. Going with the same dose as with the stock Portafilter yielded a shot that was dramatically more balanced and evenly extracted. Hmmm... I repeated this a few more tries and continued to get nice shots. Perhaps a bit lacking in the low end and not quite as sweet as I'm used to, but good shots none the less. And the volume was noticably larger (I could get about 1.5 to 1.6oz from the double with ease).
Apologies if I'm misunderstanding you, but the larger volume is not a surprise, since the bottomless PF doesn't break down crema like the spouted one does.

Because of this, the exact same shot will measure ~15% greater in volume prepared with a bottomless PF as compared to a spouted PF. Or, if you pull to the same volume, the bottomless shot will always be more concentrated (ristretto) and will often taste richer and sweeter.
-AndyS
VST refractometer/filter basket beta tester, no financial interest in the company

User avatar
malachi

#2: Post by malachi »

For the bottomless portafilter volume, I've taken to doing a "swirl and tap" to "knock down" the large bubbles in the crema. This seems to result in comparable volume with the naked and the LM portafilter (using the same basket and same coffee of course).
"Taste is the only morality." -- John Ruskin

User avatar
AndyS

#3: Post by AndyS » replying to malachi »

At what point do you do the swirl and tap?

All due respect, I don't doubt it seems to result in comparable volume, but why not weigh the shots from time to time and KNOW whether or not the volumes are comparable?
-AndyS
VST refractometer/filter basket beta tester, no financial interest in the company

User avatar
JonR10

#4: Post by JonR10 »

AndyS wrote:At what point do you do the swirl and tap?
I'm pretty sure that would be after the pull and before drinking the shot.

I like the frothy mouthfeel for straight espresso. When it comes to pouring latte art (attempting art) I like to give the shot a STIR with a spoon before I pour to avoid bubble development on top of the drink.
AndyS wrote:...why not weigh the shots from time to time and KNOW whether or not the volumes are comparable?
That would give you a measurement of mass, but mass will not correlate to volume (in this case).

We agree that using a naked portafilter results in "fluffier" espresso (bigger bubbles) than using spouted portafilter. Volume is a measurement of SPACE (not mass). I guess the bottom line is that the density is different...

User avatar
AndyS

#5: Post by AndyS »

JonR10 wrote:
That would give you a measurement of mass, but mass will not correlate to volume (in this case).

We agree that using a naked portafilter results in "fluffier" espresso (bigger bubbles) than using spouted portafilter. Volume is a measurement of SPACE (not mass). I guess the bottom line is that the density is different...
Jon, that's exactly my point. Problem is (IMHO), espresso people are extraordinarily sloppy in their use of the word "volume." It has caused much confusion, and it continues to cause much confusion.

Here's some text from a post I made on alt.coffee in Oct 2004 (link):

_________________

There are TWO distinct espresso "volumes":
1. "Apparent volume," aka "gross volume"
2. "Actual volume," aka "net volume"

"Apparent volume" is what you see in the cup as you pull the shot. It is the volumetric measurement of liquid and crema at the moment the pump cuts out. Apparent volume gradually decreases as the foam collapses.

"Actual volume" is the amount of LIQUID espresso that you extract. Since espresso is whipped up into a foam as it exits the PF, it's harder to directly measure actual volume until all the foam collapses. Paradoxically, weighing the shots is the quickest method of measuring actual volume. As you know, automatic espresso machine can conveniently keep actual volume consistent by metering the amount of water fed into the portafilter.

Very fresh beans, robusta beans, and bottomless portafilters all increase the proportion of crema delivered to your cup. This increases the apparent volume when actual volume is kept constant, and decreases the actual volume when apparent volume is kept constant.

Baristas who understand the difference between actual and apparent volume are less easily fooled when going from conventional to bottomless portafilters. They understand that the bottomless PF shot looks bigger, even though the actual volume is the same. They understand that robusta shots look bigger, even though the actual volume is the same. They understand that shots with older beans look smaller, even though the actual volume is the same.

When the bottomless PF phenomenon spread like wildfire across the net, some folks were fooled into thinking that the new portafilters magically allowed them to pull much "longer" shots. Others thought that their regular shots were higher in dissolved solids. Neither of these ideas were correct; the folks simply made the mistake of confusing actual and apparent volume.
-AndyS
VST refractometer/filter basket beta tester, no financial interest in the company

User avatar
JonR10

#6: Post by JonR10 »

AndyS wrote:Problem is (IMHO), espresso people are extraordinarily sloppy in their use of the word "volume." It has caused much confusion, and it continues to cause much confusion.
Why do you think that's a problem? There's always confusion about everything! :wink:
(How many times have we been asked "when do you start timing the shot?")

As for the correct use of "volume", it all depends on your perspective. If I consider the volume to include the crema, then I would say that "real" and "apparent" volume are the same and both reduce as the shot settles.

There's no right or wrong, only an agreement to be made about how a shot is to be measured. Since I consume the crema before it settles then I would assert that I get a larger volume of lighter-density beverage. :D

User avatar
AndyS

#7: Post by AndyS »

JonR10 wrote:There's no right or wrong, only an agreement to be made about how a shot is to be measured.
I didn't say there was a right or wrong, I just said that there was no agreement about how a shot is to be measured. In fact, most espresso people don't even know that an agreement NEEDS to be made.

Actually, an agreement only needs to be made if you're interested in seeing the art of espresso develop more quickly. If you think ambiguity and confusion are not a problem, then, never mind.

[post edited 1 time to make it a hair less obnoxious]
-AndyS
VST refractometer/filter basket beta tester, no financial interest in the company

User avatar
JonR10

#8: Post by JonR10 »

AndyS wrote:In fact, most espresso people don't even know that an agreement NEEDS to be made.
LOL - good point.
AndyS wrote:If you think ambiguity and confusion are not a problem, then, never mind.
Hmmm - this seems to twist my intended meaning about, but it's an absolutely valid point just the same. I was trying to say that agreement is necessary for clarity in communication, and in that I think we agree :)

User avatar
AndyS

#9: Post by AndyS »

JonR10 wrote:I was trying to say that agreement is necessary for clarity in communication, and in that I think we agree :)
Sorry for misunderstanding you. Agreement and communication are GOOD. :-)
-AndyS
VST refractometer/filter basket beta tester, no financial interest in the company

User avatar
cannonfodder
Team HB

#10: Post by cannonfodder »

I have been mulling around the idea of getting a bottomless PF. Not because of the added 'volume' in the shot but as a diagnostic aid. I have also seen reference to its ability to produce a thicker, buttery mouth feel (bonus!).

I would assume that the added volume is a byproduct of the direct brew path, no twists, turns or impacts with the bottom of the PF. I would think that the actual net liquid volume would be less than a traditional PF. Your are essentially measuring foam and foam will displace much more volume than a liquid. If you pull a traditional 2oz double, you actual have more of a ristretto due to the added crema. You would have to measure your shots by weight to get a closer compare. I would guess that you would have to pull about 2.5oz by volume to get the equivalent of a 'normal' double.

That is like comparing egg whites to meringue, same starting product, same starting weight but the meringue displaces twice the volume due to the incorporated air.

AAAA, too much thinking, as long as it tastes good, who cares. Jon's espresso porn photos are enough taunting to push me into getting one.
Dave Stephens