How filter baskets affect espresso taste and barista technique - Page 3

August 28th, 2011, 1:53 pm

I had a request for the complete set of physical basket data. In addition to that was shown in the original posts, we also counted the number of holes, and measured the fill weight of the basket using table salt. Below is the complete data set with the hole number after the average hole area, and the fill weights as the final column.

      B.dia H.av  H.sd H.ar N.ho H.gr NaCl.wt
fas1    288 396.7 37.5 28.2 228   0    57.9
fas2    288 382.2 25.9 27.5 248   0    57.9
lms     310 367.2 28.2 37.9 362   1    59.4
fad1    430 285.8 39.2 36.6 633   0    75.1
fad2    430 286.3 48.1 36.9 584   0    75.1
fmf1    430 342.3 30.8 59.3 640   1    77.1
fmf2    430 366.8 38.8 68.5 642   1    77.1
lmd1    430 401.9 50.7 81.9 640   1    75.2
lmd2    430 409.9 46.3 85.0 638   1    75.2
vst15   494 310.6 14.3 54.3 720   0    71.7
vst18   494 351.2  9.8 69.3 739   0    76.7
vst22   494 377.1 15.4 80.0 716   0    88.1
tr1     489 384.9 41.5 87.7 746   0    91.6
tr2     489 387.0 42.5 88.7 748   0    91.6

Please note that the hole area was calculated by summing the individual hole areas, and is not quite identical to the estimate of squaring the average hole diameter and multiplying it by pi/4 and the number of holes.

#22: Post by **malachi** » August 28th, 2011, 4:28 pm

Ian_G wrote:If I'm reading this right, this sounds very interesting. I wonder if my failure with up-dosing has been caused by using the wrong basket. I suspect - and in some cases know for sure - that many British roasts work best when using larger doses. Unfortunately I have never yet managed to appreciate them, possibly because of the dose/grind trade-off, which is one of the reasons I stick with Italian coffee.

Does anyone know if the VST or clones thereof can be used in a Elektra Semi-auto?

As a heads-up, the VST seems to have a "minimum grinder" requirement that sets a rather high bar.

August 29th, 2011, 6:20 am

This sounds intriguing. Could you explain the thinking behind it please? And also, if you know, can you say whether my Eureka Mignon will be up to the task?

#24: Post by **GlennV** » August 29th, 2011, 7:39 am

another_jim wrote: ... Espresso made from large doses taste punchier ...

This is a fascinating study. I wonder where it leaves the analysis of "Espresso 101: How to Adjust Dose and Grind Setting by Taste" and "Mano Lite: A Short Guide to Dialing in Espresso SOs and Blends" though? Similar language is used to describe the effect of updosing (More "aggressive/in your face" and "louder" respectively) yet there is an implicit change in grind associated with the updosing there, as it is in the same basket. This is undoubtedly a real effect, but I thought the change in grind was key. So, if you increase the dose and grind coarser to keep the flow the same (in the same basket) do you really get differential extraction of the caramels vs acids/bitters, which should still be detectable when cold, or is this effect more about structure/crema as well? I have neither the equipment or technique to answer this convincingly myself unfortunately.

#25: Post by **cafeIKE** » August 29th, 2011, 9:13 am

malachi wrote:As a heads-up, the VST seems to have a "minimum grinder" requirement that sets a rather high bar.

The better the grinder, the more consistent the shots. For any basket

Presumably the study used a Titan / Commercial class grinder.
The study shows the VST baskets to be the most variable for small changes in dose.

#26: Post by **RapidCoffee** » August 29th, 2011, 9:44 am

cafeIKE wrote:The study shows the VST baskets to be the most variable for small changes in dose.

Correct. One of the more interesting results of the study.

VST basket holes are more consistent in diameter than other filter baskets. But there is no reason to believe that this makes the baskets easier to use. On the contrary, it appears that you have to be more accurate in dosing the VST baskets. I have no simple explanation for this. It's probably associated with the highly heterogeneous size and shape distribution of coffee grind particles, and how they block the basket holes, and how this impacts flow...

#27: Post by **boar_d_laze** » August 29th, 2011, 11:06 am

GlennV wrote:This is a fascinating study. I wonder where it leaves the analysis of "Espresso 101: How to Adjust Dose and Grind Setting by Taste" and "Mano Lite: A Short Guide to Dialing in Espresso SOs and Blends" though? Similar language is used to describe the effect of updosing (More "aggressive/in your face" and "louder" respectively) yet there is an implicit change in grind associated with the updosing there, as it is in the same basket. This is undoubtedly a real effect, but I thought the change in grind was key.

It is. At least to the extent that grind is variable and basket is fixed. Start messing around with lots of parameters and it's difficult to fix the specific contribution of any in particular. Grind is the simplest and least expensive component to vary on a daily basis and produces profound changes.

So, if you increase the dose and grind coarser to keep the flow the same (in the same basket) do you really get differential extraction of the caramels vs acids/bitters, which should still be detectable when cold, or is this effect more about structure/crema as well?

Does such an adjustment (coarser/more) change both (balance/texture)? Yes, it does. You have to nail things down considerably further before you're going to get me to say more.

I have neither the equipment or technique to answer this convincingly myself unfortunately.

Pulling shots means an interdynamic chain -- the 4 Emms, if you will -- and any significant change anywhere in the chain will change the cup. If you've got a sufficiently consistent grinder and can afford a couple of baskets to fool around with, you can get a pretty meaningful answer for your particular chain -- which will be THE meaningful answer as far as your daily coffee is concerned.

It's a good idea to remember:

1. Thou shalt not take quantification too seriously;
2. Science is a question, not an answer;
3. Statistics is a science allowing insight into the behavior of a large population of anonymous objects, and not anything else. The smaller the population and the better identified the objects of the discussion, the more limited the utility of the statistical analysis.
4. Your taste is the most important measurement;
5. Thou shalt not take any of this too seriously;
6. Your taste is the most important measurement;
7. Your wife is not only always right, she can make you unhappier than any cup of coffee, and can do things for you no beverage can; therefore
8. Thou shalt cater to her tastes; otherwise
9. Your taste is the most important measurement; and
10. Your taste is the most important measurement.

BDL

August 29th, 2011, 12:26 pm

GlennV wrote: I wonder where [this study] leaves the analysis of "Espresso 101: How to Adjust Dose and Grind Setting by Taste" and "Mano Lite: A Short Guide to Dialing in Espresso SOs and Blends" though? Similar language is used to describe the effect of updosing (More "aggressive/in your face" and "louder" respectively) yet there is an implicit change in grind associated with the updosing there, as it is in the same basket. This is undoubtedly a real effect, but I thought the change in grind was key. So, if you increase the dose and grind coarser to keep the flow the same (in the same basket) do you really get differential extraction of the caramels vs acids/bitters, which should still be detectable when cold, or is this effect more about structure/crema as well? I have neither the equipment or technique to answer this convincingly myself unfortunately.

A very good point; and I'll need to try it out; This is the first time I started tasting espresso cold; mainly because the initial taste was so different in the different baskets, and I couldn't believe it.

My feeling is that there is a difference in taste between the two effects. Under-extracted shots taste cartoonish, with powerful acidity and peel-like cutting flavors. The high dose baskets with proper extraction taste more like 100 and 120 proof whiskeys, when you are used to the 80 proof ones -- extra oiliness and extra punch, but roughly the same flavors.

However, this is an area where expectations are likely to trump actual taste; so I'll need to blind taste the same dose done at a finer grind in a high dose basket and at a coarser grind in an overdosed small basket to assure myself that the distinction is real.

#29: Post by **malachi** » August 29th, 2011, 12:55 pm

Ian_G wrote:This sounds intriguing. Could you explain the thinking behind it please? And also, if you know, can you say whether my Eureka Mignon will be up to the task?

I have no familiarity with that grinder, sorry.
My experience has been that a grinder that is not of "commercial quality" is going to be at the very least challenging with the VST baskets. Keep in mind that these baskets were developed for commercial use and to solve commercial problems. As such, they were developed and tested using commercial equipment.
I would say that anything equal to or of lesser quality to a Super Jolly is simply not up to the task. It's not that you won't be able to get great shots using these baskets - it's just that you will probably struggle to gain consistency doing so.
I found that a Robur was up to the task, but that the Anfim Super Caimano was perhaps even better suited. So that's the category that you should probably be looking at.

#30: Post by **Ian_G** » August 29th, 2011, 1:25 pm

malachi wrote: It's not that you won't be able to get great shots using these baskets - it's just that you will probably struggle to gain consistency doing so.

I think I understand. These baskets were designed to nullify one area of shot inconsistency, but wont have any effect on grinder variability.

Edit: I wonder to what extent this is an issue for mid-range grinders such as mine. They are more consistent that cheaper versions, but not as consistent as commercial ones. However as James Hoffman pointed out, commercial grinders have not really evolved since the sixties and more importantly a commercial grinder running flat out in a commercial setting overheats and the burrs expand causing inconsistency. Compare that to a domestic machine that runs maybe once an hour, if that, and perhaps the difference in variability is not so much.