Spinning for distribution? - Page 3

[AndyS]

Yeah, it's wacky, but you gotta try stuff. You just may end up, in your waning years, using a Centridistrofuge (tm)* to dose and distribute your morning espresso.

I'm with Cannonfodder on this one; you don't have to try everything. I will allow my portafilter to be put in a Centridistrofuge (tm) when they pry the portafilter from my cold, dead fingers.

[The_Mighty_Bean]

Well, thanks to those who weighed in on the side of adventure. While I was mostly joking in my comment to Jon about an espressoporn showdown, I have to admit that my back hairs (how did you know I don't wax in the winter?) did prickle a bit in response to the perceived slap-down against the spirit of inquiry. I mean, this is the place where I first found charts of Total Dissolved Solids, and eye-popping temperature curves generated by $200 Fluke thermologging devices. But then I start wondering about the physics of powder distribution and, whoa Nellie, we're over the edge!

Well, cover the eyes of the Newbies, 'cause it's about to get technical in here. Those who are satisfied with their morning cuppa, and/or only have 45 seconds to distribute their coffee in the basket can go back to enjoying your coffee. We'll call you if anything interesting develops over here, that fits into your enviably brief HX routine.

One of the most important questions in distributing coffee properly is the role of "fines". Dan stated in another thread (which I can't find to save my life) that, in his experience, tapping the basket to excess tended to migrate the "fines" to the bottom of the basket, which produced an extraction that emphasized the flavor components ordinarily present in the first third of the pour. I believe he called it "front loaded". Of course this is only one person's (considerable) experience, and it would be nice to have some more data on this taste experience, but let's take it at face value for now.

The nice thing about vibrating a basket down to the maximum tapped density of the grounds is that you get a puck density, pre-tamp, that is consistent for a given substance. My source for that statement is the Autotap brochure, referenced in a previous post.

Who cares? Well it's got two applications:

1. Consistency of extraction - maximum tapped density and a flat surface means you've taken out airspace and levelled the puck. Ergo, there shouldn't be channeling. (In "Some Aspects of Espresso Extraction" Jim Schulman mentions the phenomenon of "microchanelling", I don't know what the devil that is, let's leave it alone for the moment until someone enlightens us).

2. Consistency across experiences - Use the same batch of beans, grinder, PID'ed machine, and a measured tamp, and you and have a remarkably consistent tool for comparing shots. (If you're really lab-technical you use a digital tool for measuring burr spacing, and you measure ambient humidity and and measure TDS and volumetric water dosage, and probably control for more variables that I'm not thinking of at the moment).

Anyway, it's one step closer to a reference standard for the puck.


Now Andrea Illy goes and complicates, perhaps even destroys, this whole theory, by telling us this interesting tidbit, on page 215, crudely summarized below:

An espresso puck is a heterogeneous ("plurimodal") mix of coarse and fine particles. The coarse bits create a structure that limits the water flow. The fine bits are what contain the flavor components. Therefore, a distribution that homogenizes the puck or separates it by particle size is going to be undesirable.


This may account for the flavor change Dan was noticing when more fines migrated to the bottom.


Thus, it seems that our goal is to create a uniformly distributed mixture. That's probably part of the reason why the WDT works so well. Nonetheless, we also want that mixture to be at maximum pre-tamp density without differentiation by particle size. Otherwise, when we press down that tamper, we're pressing on a surface with uneven pockets of airspace, and creating space for channels. If you're good, you can get close to that ideal with stirring (for clumps and mixing), thumping (for the bottom layers), and Stockfleth's (for the top) , and then the lovely E61 erases any lingering errors with a nice, gentle pre-infusion.

BUT....

I'm still betting that you can get an improved shot with some mechanical means that does the equivalent of sift/stir/thump/level all the way to maximum tapped density. And it should work well for those with less expensive equipment and less-practiced barista skills.

You'll still need a light tamp. Illy says so. How hard doesn't really matter, you just need enough pressure to release the oils and stick the particles together, which creates a more even resistance against the water flow. Sorry, no time to go back and find the page but it was contained within the 2nd or 3rd page of the search results for "distribution".

It seems like an ounce of experimentation here might be worth a pound of theory. I'm going to keep reading for now, but next month when I have more time I'll probably start messing around with vibration and spinning and maybe even vacuum suction. Anybody who has gotten similarly curious is cordially invited to experiment as well. If it doesn't work on our coffee, maybe Dr. Ruth will buy our patent.

~tMb

P.S. If anyone would be kind enough to save me $100 and loan me a copy of Illy's book for a month so I can quit trying to read it online through creative Amazon searches, I would be very grateful. Or I could offer a barter in the form of Barnes and Noble gift cards.


P.P.S. Again, gotta run no time to go back and find the page but worth looking at is the place where Illy discusses what a PITA it is to sift ground coffee because of the oils that stick different-size particles together.

[Matthew Brinski]

I have just read this thread for the first time today, but ...

It's documented on this site, by certain extremely experienced and well-regarded members, that hand distribution is unreliable and difficult

... could someone please help me understand the rationale behind this statement? This is not an attack on the individual who posted, but a general question due to the underlying theme that dissecting needles, yogurt cups, ramekins, paper clips, shakers, etc., are needed to prepare espresso without great difficulty. I honestly don't get it sometimes.

Peace.

[Psyd]

I'm with Cannonfodder on this one; you don't have to try everything. I will allow my portafilter to be put in a Centridistrofuge (tm) when they pry the portafilter from my cold, dead fingers.

Cheers, and like I said, no one is telling you that you have to. that's still no reason to suggest that those that want to play and experiment are somehow ruining it for the noobs or desecrating a holy ritual or something. These folks are the type that have fueled innovation for millenia. Lots of them have died doing silly stuff, but those that have survived have been what's given us crops, domesticated animals as beasts of burden and a food source, indoor plumbing, the arts, HVAC, cars, radio, television, and espresso machines. Leave 'em play, I say.
Look, I haven't the time or the inclination to gather together three machines of nearly any sort here, but I'm so happy that some folks will. I don't have time to go through the experimentation required to devise a water dance for my HX, or a surf regimen for my Silvia, nor do I have the time to learn my lever from scratch. Nearly every detail of pulling shots that I've learned, I've learned from people like the ones considering spinning baskets. I let them do all of the work, and scroll down to the bottom of their threads, and get to the results. If they've come up with something that makes the coffee better, I try it. If it works for me, I steal it! It's these very folks and their efforts that made me the accomplished barista from the noob that I came here as. Of course, if I get to the bottom and they say it was a total failure, they've just saved me a whole raft of time.
Cheez, if it weren't for some guy like them, bored, out watching goats eat berries, we wouldn't even be here!

[Psyd]

... could someone please help me understand the rationale behind this statement? This is not an attack on the individual who posted, but a general question due to the underlying theme that dissecting needles, yogurt cups, ramekins, paper clips, shakers, etc., are needed to prepare espresso without great difficulty. I honestly don't get it sometimes.

Quite often, some posters aren't able to afford the best machinery out there, and what they are able to get their hands on will sometimes have shortcomings. Some innovative person with more time than money will attempt to overcome these shortcomings, and when he does, he posts the secret, hold-your-tongue-right method of getting great results from less-than-stellar kit. It works, so others adopt it and have better espresso, so it becomes popular. If it didn't work, it'd die on the delivery table.
Some folks have superior kit from the get-go, so they don't see the results that those with the middle of the road kit will, so they don't understand the gyrations. Some folk don't see the difference between what they get with the additional technique and without because their palate will accept either result as good enough (bless them, I wish I were still one!) and they won't understand why you'd do those things either.
Those that want better and don't want to spend next years mortgage to get it will try anything, and adopt what works for them.

[RegulatorJohnson]

i think you would have time better spent on redesigning the grinder instead of the doser.

jon

[DigMe]

I mean, this is the place where I first found charts of Total Dissolved Solids, and eye-popping temperature curves generated by $200 Fluke thermologging devices. But then I start wondering about the physics of powder distribution and, whoa Nellie, we're over the edge!

These things are different in that no one is proposing or trying to create these temp curves or charts as part of his/her morning routine. As far as shot-prep goes - most of the ideas proposed here at HB that are sorta outside of the normal cafe routine still consist of fairly quick moves or things that do not severely slow down the process. Remember - most of us have limited time in the mornings to prepare our espresso before work. We can tweak a lot of things in our free time that will improve the shots we pull in our pressed time but I personally have no room in my morning routine for elaborate processes added on top of the normal shot prep.

brad

[The_Mighty_Bean]

Rapidcoffee, thanks for your comment. I have the same problems with shaking the basket. You end up with a nice dense puck but the distribution is uneven and hard to correct without one of those Australian downdosing scrapers I keep hearing about. I tried Stockfleth's for Dummies on those well-settled pucks, but I always end up with results that are less than perfectly level. Still, I've gotten some excellent, syrupy, high-TDS ristretto pours, using the shaken basket, plus some of your celebrated technique to re-fluff and level the top.

I also used a vibrator with poor initial results. I didn't detail all the crazy stuff I went through. I tried two weaker vibration devices before settling on the big plug-in back massager that I wrote about. Neither one of the smaller devices worked well, so I see why you gave up. But from trying the big one, it seems that sufficiently strong, vibration, centered under the basket, gets the grounds spinning in a vortex-like shape that looks a lot like a sloow version of the spinning part of milk-frothing. I bet that sort of strong, centered vibration, paired with rotation of the basket would yield a good result. That's where I'm likely to start experimenting.

Regulator, meant to thank you for the link to the thread about how deceiving looks of the pour can be. That was interesting reading. Also, re: your comment about best approaching this issue through grinder modifications, I think Versalab is doing a great job at that, for $1500 and up. And they have said clearly that it is their intent to keep costs down, but retain design quality. Frankly, I haven't the tools, nor the first idea how to improve on an espresso-quality grinder, let alone how to do it for under $100.

But spinning and vibrating and vacuuming- all those things can be done quite inexpensively, and they're simple for us to mess around with at home to see if they improve the pour.

DigMe - agreed, and my goal is to come up with something quick, practical and cheap.

Matthew - did Chris answer your question?

Psyd, thank you for your kind words and eloquent defenses of innovation. You're absolutely right. Nobody here knows this, but I invented the internets.

~tMb

[Randy G.]

.........
In any case, if you were to put the entire basket on the inside of a spinning thing, with the opening of the basket facing the center of the rotation, would it distribute any better or simply be a very complicated method of 'thumping'?

"HEY! Why are all those portafilters embedded into the walls and ceiling? And why do you wear that helmet when making espresso? And what ever happened to your dog?"

[The_Mighty_Bean]

"HEY! Why are all those portafilters embedded into the walls and ceiling? And why do you wear that helmet when making espresso? And what ever happened to your dog?"

I don't know, but it all came to a sorry end when my wife left me and ran off with my vibrodistrocentrifuge.

[The_Mighty_Bean]

I started an important background thread HERE, to discuss what exactly is the role of "fines", whatever those might be, within the puck.

-the Inquisitive bean

[Matthew Brinski]

Matthew - did Chris answer your question?

My question regarding the meaning of this? -

It's documented on this site, by certain extremely experienced and well-regarded members, that hand distribution is unreliable and difficult

No, not really.



.

[The_Mighty_Bean]

Now Andrea Illy goes and complicates, perhaps even destroys, this whole theory, by telling us this interesting tidbit, on page 215, crudely summarized below:

An espresso puck is a heterogeneous ("plurimodal") mix of coarse and fine particles. The coarse bits create a structure that limits the water flow. The fine bits are what contain the flavor components. Therefore, a distribution that homogenizes the puck or separates it by particle size is going to be undesirable....


You'll still need a light tamp. Illy says so. How hard doesn't really matter, you just need enough pressure to release the oils and stick the particles together, which creates a more even resistance against the water flow. Sorry, no time to go back and find the page but it was contained within the 2nd or 3rd page of the search results for "distribution".

I went back and looked. These concepts are more fully discussed on p277-78 of the Illy book. Currently being discussed on the "role of fines" thread that I spun off of this one.


~tMb

P.S. Matthew, I spent a ton of time searching but I just can't find one of the two quotes I remember. Please forgive me for not linking to this first one, but in the experiment that Ken and Jim ran on the role of preinfusion, Ken stated that Jim did the dosing, because Ken could not imitate his technique.

Okay, when two people as experienced as Ken and Jim agree that their difference in dosing/distribution method is substantial enough that it's too inconsistent to use in a statistical comparison of shots, that tells me that, for sure, you and I and Joe amateur-home-barista are doing different things to the beds of ground coffee we're working with.

In other words, distribution techniques are unreliable as a tool of comparison, and make a difference in flavor.

There's a second post that I couldn't find, and I could swear it was Ken or Jim again, and it was, once again a comparison thread. Might have been somewhere in the Titan grinders mega-discussion. Anyway, the person posting made a complaint to the effect that the distribution was less than ideal because it was inconsistent between testers.

The only way to standardize the compaction aspect of distribution is to get it down to a fixed pre-tamp density. Once it's there, if we use the same tamp (e.g. Espro or Autotamper), then we are working with samples that are identical in that respect.

I also am intuiting that this max-density, evenly-distributed puck is going to consistently taste and pour better.

There's much experimenting to be done, for those inclined to do so, to establish whether there's any merit to my crazy little idea.

~bean

[RegulatorJohnson]

i think based on that... that it is inconsistent from one person to another.

..but i bet the same person would be consistent with them self.

jon

[barry]

I have the same problems with shaking the basket. You end up with a nice dense puck but the distribution is uneven

how do you know?

[barry]

Okay, when two people as experienced as Ken and Jim agree that their difference in dosing/distribution method is substantial enough that it's too inconsistent to use in a statistical comparison of shots, that tells me that, for sure, you and I and Joe amateur-home-barista are doing different things to the beds of ground coffee we're working with.

In other words, distribution techniques are unreliable as a tool of comparison, and make a difference in flavor.

When the variable being tested is not grounds distribution, it makes sense that the distribution being used should be consistent. That does not necessarily mean that interpersonal variations in distribution impact the cup quality, only that it was a test of Variable A and not Variable B, and by holding Variable B constant, they reduce any impact that it might have so as to make the statistics on Variable A valid.

Further, as much as I like Ken and Jim, and they're both good friends, they really aren't that experienced when it comes to making espresso. Perhaps as home enthusiasts, they rank right up there, but I know plenty of folks who make more espresso drinks in a week than those guys make in a year.

I also am intuiting that this max-density, evenly-distributed puck is going to consistently taste and pour better.

but haven't you already declared that this isn't going to be an "evenly-distributed puck" by forcing the fines to separate from the coarses in the matrix through vibration?

[popeye]

It's documented on this site, by certain extremely experienced and well-regarded members, that hand distribution is unreliable and difficult

... could someone please help me understand the rationale behind this statement?

At first glance, I was confused - i mean, how difficult is distribution? But then i compared it to most other steps of pulling an espresso, and it seems that there is probably the most "art" and least "science" associated with distribution. Compare it to: grinding (done by a machine), tamping (generally agreed as less important than distribution) and pulling the shot (done by a machine). Even with variables where experience counts - choosing the grind, deciding how hard to tamp, and deciding what temperature and pressure to pull the shot at - are more about decisions (setting the grinder/machine) than actual technique. The prevalence of techniques associated with distribution - the stockfleth move, the WDT, etc. - show how much of an art distribution is.

So, comparatively, i would argue that hand distribution (as opposed to the proposed vibratory distribution) is unreliable and difficult. Perfect distribution is very complex. Even our rudimentary measurements of distribution - through the absence of channels, through taste, or through the use of a bottomless portafilter - are just that, rudimentary.

Undoubtedly, most of us are quite good at distribution. But we've gotten there through much trial and error. And none of us can claim to be perfect at it. In fact, further improvements are elusive, because we are dealing with very small particles (microns in size?) with very rough tools (fingers and needles). If distribution is currently an art, we are very good artists. But there's no need to be afraid of science. Let science proceed, and those who wish to use it's tools do. Personally, i keep my fingers crossed. As long as my art is better than the science of the superautomatic, I think the end of the barista is nowhere near.

[The_Mighty_Bean]

i think based on that... that it is inconsistent from one person to another.

..but i bet the same person would be consistent with them self.

jon

As we attorneys (well, future attorneys in my case) like to say in our pleadings, "I hereby incorporate by reference" what Popeye just said.

We are dealing with very small particles, with huge and clumsy tools. You're never going to push around a hundred thousand microparticles in the exact same way.

A practiced, competitive barista will be most consistent, a skilled home user less so, and so on down the line. Not one of them will be consistent with another.

I've been at this for over a year, I make several shots a day and it is patently obvious to me, each and every time I make a shot, that sometimes there's a few more grinds pushed into a "hole" that I need to fill, and sometimes a few less.

So there's definitely variance in distribution. The question is how much variance makes a difference that you can see in the pour and, more to the point, taste?

But, if I may flog the dead horse once again, if you get that puck to max tapped density, then that variance is drastically reduced, because the tapped density is supposedly constant for a given substance.

Once you have that consistent puck, it's easy to test and adjust for flavor issues.

tmb

[The_Mighty_Bean]

how do you know?

It's visible on inspection. The grounds in the basket heap up on one side or form peaks and valleys, and grounds in the shaken basket settle in lower than if it had not been shaken. It's like tapping- it leaves visible room for updosing.

When the variable being tested is not grounds distribution, it makes sense that the distribution being used should be consistent. That does not necessarily mean that interpersonal variations in distribution impact the cup quality

.

The test was for effect of preinfusion on cup quality. If individual distribution technique wasn't at least thought to possibly have an outcome on the final cup, there would have been no need to standardize it. If its not a variable, then there's nothing to worry about. --edit-- You are right, I stated it above as a fact. It -is- an established fact if you talk about a newbie's distribution attempts versus an accomplished barista. One you get to higher and higher levels of competence in the art, the differences grow smaller and possibly at some point become negligible. Again I refer to Popeye's post.

Further, as much as I like Ken and Jim, and they're both good friends, they really aren't that experienced when it comes to making espresso. Perhaps as home enthusiasts, they rank right up there, but I know plenty of folks who make more espresso drinks in a week than those guys make in a year.

True, but if it takes the likes of Chris Tacy to get consistent distribution by hand then it's probably not a bad idea to look for new methods that can give folks like you and me a helping hand.

but haven't you already declared that this isn't going to be an "evenly-distributed puck" by forcing the fines to separate from the coarses in the matrix through vibration?

No, well, maybe. LOL. I'm figuring this thing out as I go, not declaring laws. If I declare something as a rule, then I've cited a source for it (I hope).

I'm trying to figure out if there's an "ideal" intra-puck distribution of fines, which is why I spun off that other thread. And I have also suggested a way to get consistently dense pucks. I'm not sure how the fines would be distributed at max tapped density.

There's a whole lot I don't know, and some of it may be a lot easier to solve experimentally. Thanks for your thought-provoking response. Also, I need to get my hands on that Illy book.


-bean, confusedly

[Matthew Brinski]

True, but if it takes the likes of Chris Tacy to get consistent distribution by hand then it's probably not a bad idea to look for new methods that can give folks like you and me a helping hand.

Um, dude ...

Not that it automatically makes him correct, but do you understand that you're having a conversation with an established USBC judge? I just thought I would point it out after reading the "give folks like you and me a helping hand". (And I've been told that he's pulled a few shots)

... he's gotta be pretty cool, 'cause he has designated helicopter parking at his coffee shop.


Matt