Is single dose [without hopper] grinding inconsistent? - Page 2

#11: Post by **cannonfodder** » July 25th, 2007, 10:49 pm

I will toss in my observation with the Kony. The beans most definitely popcorn when there is nothing above the burrs. The beans jump up into the hopper and you can clearly hear the beans jumping around in the grinding video I did way back when.

I kept a quarter to half pound in the hopper when I was using it. During my testing sessions I would grind and pull multiple back to back shots. During those sessions I would occasionally run out of beans in the hopper because I was not paying attention. Those last 'end of the hopper beans' shot would run noticeably faster hence my assumption that the grind changes when the hopper is empty. I believe Dan had the same observation, when the hopper went empty, that shot suddenly ran fast.

However, if the grind was adjusted from the start for that single dose method of grinding, I don't think it would make much difference. I noticed that as long as I had a couple of shots worth of beans in the hopper, plus the one I was grinding so around 45g of coffee, I did not notice a difference.

Jim mentions a press pot, while I did not mention it when I had the Kony I did make a couple of awesome press pots using it.

July 26th, 2007, 12:21 am

cannonfodder wrote:However, if the grind was adjusted from the start for that single dose method of grinding, I don't think it would make much difference. I noticed that as long as I had a couple of shots worth of beans in the hopper, plus the one I was grinding so around 45g of coffee, I did not notice a difference.

So in a nutshell, sounds like if you want consistent results be consistent. Just like virtually any other aspect of coffee!

July 26th, 2007, 12:52 am

another_jim wrote:
Ken, you keep stressing the proper way to use these grinders. This is, to my mind, meaningless, or at least ambiguous.
-- Some people will buy these grinder for busy bars, keep the dosers filled, and be interesting how accurately the dosing adjustment, and how reliably the automatic refill, work. They may also want to know how well a "don't touch the grind setting" policy works over the course of a day. This may be the most proper way of testing the grinders, since that is what the engineers intended, and the market for which they are built.
-- For others, proper usage may be suitability for Barista championships and third wave coffee stores. In this case, the key will be how fast and accurately it dials in, how accurately a timer doses the coffee, how well the doser distributes the grinds into the basket, and how consistently the shots flow. Greg lives in this world, and that is what he wants to know. It is also an entirely proper set of issues
-- For others again, it may be about having one coffee grinder for the home of a coffee lover. It should be useful switching between three or four different coffees, and for espresso, drip and presspot brewing. This is my own need. More importantly, if someone were to ask me how adaptable a commercial grinder is for home use, this is the criterion I think is objectively the correct one to use for its ergonomics. By testing the grinders hopper-less, I'm addressing the questions of this category of user. I think that too is entirely proper.

I choose to test for the third kind of user, since that is who I am. If you think this is self-indulgent, you may be right. But I doubt I'd be of any greater use to the community testing these grinders in some way I don't intend to use them. My heart wouldn't be in it, and I'd be mailing it in.

In any case, I didn't see anyone falling over themselves volunteering to do definitive taste and accuracy tests on the auto-fill dosers

Jim,

I don't want you to do anything that you are uncomfortable with or that your heart isn't in, but:

The other reviewers have done (mostly) descriptive reviewing, which I think is just fine. What they have written is clearly composed of opinions, educated opinions to be sure, but opinions nonetheless. A lot of what you have written also falls into this category and as such is clearly labeled.

What I take issue is the air of science, the whiff of this, that comes from posting precise tasting scores and one on one grinder comparisons ala, "can it beat the Robur?" I don't believe that this is adequately controlled because I believe you are not using these grinders within their "specs," i.e. there is no bean load above the beans that are being ground for the shots you are tasting. If you would more clearly label these tasting results as being your opinion only and perhaps being limited by the hopperless arrangement you are using, then I'd have no issue with any of this.

ken

#14: Post by **another_jim** » July 26th, 2007, 3:12 am

I think

And Now for the Entertainment Portion of this Review

as the very first thing I say, is more than adequate to dispel the air of science. The scores are boxing scores, round 1, round 2, etc.

I am adding the detailed scores that I'm keeping for later analysis at Teme's request. Teme is not one of the grinder testers, since shipping the grinders to Copenhagen is somewhat awkward. He is, however, one of the heavy hitters when it comes to this whole review process. He has done exemplary work testing a whole set of grinders there, including publishing and interpreting the first ever enthusiast generated particle size comparisons among top grinders. Dan and the rest of us are eager for any input he might give to the final article. If he wants to see the detailed data, he gets it.

I'll be using the same scoring and data collection format to test pairings of the smaller grinders among themselves. By doing such additional tests, and also using the detailed sheets from the blind sessions I did with Marc, I can check whether the data are mutually consistent and usable. If they are, I'll post a statistical analysis with all the caveats that they are based on hopper-less grinders.

Finally, the other reviewers have done blind testing, not just judgment based impression gathering. I'm not for a moment granting that their results apply only to hopper operation, while mine apply only to hopper-less operation. But if it turns out that our results are fundamentally inconistent, then that may well be the reason, and I'll be eating crow.

But for now, relax, I'm doing a grinding reality show, the non-prime time, summer rerun season, entertainment portion of the review.

#15: Post by **RapidCoffee** » July 26th, 2007, 3:53 am

Ken Fox wrote:What I take issue is the air of science, the whiff of this, that comes from posting precise tasting scores and one on one grinder comparisons ala, "can it beat the Robur?" I don't believe that this is adequately controlled because I believe you are not using these grinders within their "specs," i.e. there is no bean load above the beans that are being ground for the shots you are tasting. If you would more clearly label these tasting results as being your opinion only and perhaps being limited by the hopperless arrangement you are using, then I'd have no issue with any of this.

Ken, these are valid points. However, as much as I love having a commercial grinder in my kitchen, I would give it up in a New York minute if I had to use my Super Jolly per design specs (i.e., the way it would be used in a commercial establishment). Fill the enormous bean hopper with a kilogram of beans? Keep the doser half full of grinds so that one stroke consistently yields a single dose and two strokes a double? No thanks. Standard commercial practice, but completely unsuitable for the home barista.

A more likely scenario for the home user: store roasted beans in airtight canisters, and grind per shot within seconds of the pour. I see nothing wrong with modifying the equipment in minor ways to achieve this (e.g., losing the hopper or defeating autogrind). Ditto for adjustments to technique (e.g., thwacking the doser). Such alterations to original grinder design specs do a far better job of reflecting typical home use.

However, the question of bean weight in the hopper really should be tested. I'm already slated to run a bunch of particle size analyses. Perhaps I'll add one more comparison: a single shot ground in my SJ with and without the weight of a tamper, in each case adjusting the grinder to give similar pour timings. If the particle size distributions are similar, this would support the hypothesis that weight on the beans is unnecessary. If they're different, it would indicate the need for more study. Would that help allay your concerns?

Dang it, I so do not want to keep a kilo of beans in my hopper...

#16: Post by **Matthew NB** » July 26th, 2007, 6:34 am

I have read all posts in the TGP and related threads. To me it has become evidently clear that it will be extremely difficult to make this a "scientific" test with hard conclusions, even if HB had many more resources. There are so many variables and personal preferences that a definite outcome of Grinder C> Grinder A> Grinder D etc.. is unlikely.
Fortunately, we are still learning quite a bit in the grinder department due the efforts of all testers involved.

I agree with Ken that testing the grinder hopperless is out of the original design purpose and therefore could lead to different results. Nevertheless, the testing of Jim in this thread is valuable because more than a few people do want to run the grinders hopperless and modified.

Some of the remarks, which are most of the time very valid, made in these threads could come off as hostile to the testers.
But I am sure non of these are meant in that way and we all are very appreciative of your hard work. So please keep going

July 26th, 2007, 10:58 am

Some of the remarks, which are most of the time very valid, made in these threads could come off as hostile to the testers.
But I am sure non of these are meant in that way and we all are very appreciative of your hard work. So please keep going

I wouldn't worry too much about that. Most of us know each other fairly well, at least through these forums. As for Jim and myself, we have been friends a long while and see each other with some frequency. Jim is actually coming to visit me in about 6 weeks, at which time we hope to do some more formal testing, if we can agree on what is worth testing, that is.

ken

July 26th, 2007, 11:05 am

RapidCoffee wrote:Ken, these are valid points. However, as much as I love having a commercial grinder in my kitchen, I would give it up in a New York minute if I had to use my Super Jolly per design specs (i.e., the way it would be used in a commercial establishment). Fill the enormous bean hopper with a kilogram of beans? Keep the doser half full of grinds so that one stroke consistently yields a single dose and two strokes a double? No thanks. Standard commercial practice, but completely unsuitable for the home barista.

A more likely scenario for the home user: store roasted beans in airtight canisters, and grind per shot within seconds of the pour. I see nothing wrong with modifying the equipment in minor ways to achieve this (e.g., losing the hopper or defeating autogrind). Ditto for adjustments to technique (e.g., thwacking the doser). Such alterations to original grinder design specs do a far better job of reflecting typical home use.

However, the question of bean weight in the hopper really should be tested. I'm already slated to run a bunch of particle size analyses. Perhaps I'll add one more comparison: a single shot ground in my SJ with and without the weight of a tamper, in each case adjusting the grinder to give similar pour timings. If the particle size distributions are similar, this would support the hypothesis that weight on the beans is unnecessary. If they're different, it would indicate the need for more study. Would that help allay your concerns?

Dang it, I so do not want to keep a kilo of beans in my hopper...

For the record, as I've made obvious in pictures I've posted, I'm not using my Compak conical with its original hopper, either, although I have made a point of using it almost all the time with a bean load on top in the hopper I have improvised. My Cimbali grinders do not lend themselves to easy modification, however they are much more "kitchen friendly" in their stock configurations.

There is absolutely no doubt that most of these enormous grinders are out of place in a home kitchen, and if they are to be used in one they will be modified. The one thing I would be loathe to modify, especially in a formal review, would be operating without at least a layer or two of beans above those being ground, as I believe this is one modification that could easily effect grind quality.

Your testing, John, although interesting, would only give us information on the one grinder that you are doing particle size distributions on (SJ), so it couldn't really be generalized beyond that.

ken

July 26th, 2007, 11:10 am

another_jim wrote:I think as the very first thing I say, is more than adequate to dispel the air of science. The scores are boxing scores, round 1, round 2, etc.

I am adding the detailed scores that I'm keeping for later analysis at Teme's request. Teme is not one of the grinder testers, since shipping the grinders to Copenhagen is somewhat awkward. He is, however, one of the heavy hitters when it comes to this whole review process. He has done exemplary work testing a whole set of grinders there, including publishing and interpreting the first ever enthusiast generated particle size comparisons among top grinders. Dan and the rest of us are eager for any input he might give to the final article. If he wants to see the detailed data, he gets it.

I'll be using the same scoring and data collection format to test pairings of the smaller grinders among themselves. By doing such additional tests, and also using the detailed sheets from the blind sessions I did with Marc, I can check whether the data are mutually consistent and usable. If they are, I'll post a statistical analysis with all the caveats that they are based on hopper-less grinders.

Finally, the other reviewers have done blind testing, not just judgment based impression gathering. I'm not for a moment granting that their results apply only to hopper operation, while mine apply only to hopper-less operation. But if it turns out that our results are fundamentally inconistent, then that may well be the reason, and I'll be eating crow.

But for now, relax, I'm doing a grinding reality show, the non-prime time, summer rerun season, entertainment portion of the review.

Jim,

I think the risk here is that real differences among the grinders could be masked by too many things being fudged. The easiest conclusion to reach in a project like the TGP is that there is no discernible difference, but if there really is one then we are limiting our results to, "it doesn't matter, go buy any decent grinder and you will be fine." Although there is obvious truth to this last sentence, I'd rather have this time consuming TGP show slight differences, which the reader would then be free to decide were not worth paying for, either in real money or in the inconvenience of having such a leviathan grinder in one's kitchen.

ken

#20: Post by **RapidCoffee** » July 26th, 2007, 2:04 pm

Ken Fox wrote:Your testing, John, although interesting, would only give us information on the one grinder that you are doing particle size distributions on (SJ), so it couldn't really be generalized beyond that.

The same observation applies to any study, including your work comparing vibe vs. rotary pumps. I could point out that your results apply only to your Cimbali Junior espresso machines, whatever grinders you used for the study, and that particular batch of beans. Ditto for your more recent article on freezing greens. But those studies are still valuable, providing (at least) a starting point for future investigation. That's all I'm suggesting here.

Ken Fox wrote:I think the risk here is that real differences among the grinders could be masked by too many things being fudged. The easiest conclusion to reach in a project like the TGP is that there is no discernible difference, but if there really is one then we are limiting our results to, "it doesn't matter, go buy any decent grinder and you will be fine." Although there is obvious truth to this last sentence, I'd rather have this time consuming TGP show slight differences, which the reader would then be free to decide were not worth paying for, either in real money or in the inconvenience of having such a leviathan grinder in one's kitchen.

All the Titan grinders are more than capable of producing excellence in the cup, so to some extent we're talking personal preferences rather than better or worse. Good grind quality and ergonomics are to be expected from grinders in the $1K price range, and I think the Titans deliver.

I'll be pleased if we reach consensus on a few general issues, such as fundamental differences (if any) between flat/planar burr grinders and conical burr grinders. (And perhaps dispel some of the recent hype surrounding conicals.

) The TGP testers (Dave, Jim, Ken, Dan, and I) have all noticed the high forgiveness factor associated with conical grinders, and that may be one of the most compelling conclusions of the study. Tastewise, there's less consensus - neither Dave nor I are rushing out to buy a conical just yet.

Is single dose [without hopper] grinding inconsistent? - Page 2

Do you dose and then run the grinder until empty for each espresso?