Just about the hopper bit.
Air will still get in from the coffee exit chute through the burrs, unless you want to seal that up to and take it off for each time you grind.
I was reading the "Choice of grinders..." thread on this part of the forum and it struck me that some of the members suggested not to weigh the beans for every shot but to keep around 4cm of beans in the hopper. This is to ensure that no "popcorning" goes on inside the grinder while we grind. Frankly this is the first time I have ever heard this term and I have to say Im a bit surprised.
I have an MDF grinder, its not top notch and not perfect but it does the job quite ok. I always weigh the beans before grinding and dose only what is needed for one shot. After reading about popcorning I thought about switching to more beans in the hopper but there could be a problem with the freshness. You see I order fresh coffee from a local roaster and dont roast myself. This means that I try to keep the beans as tightly packed as possible to get the most out of them for the maximum amount of time. Keeping my daily dose in the grinder (thats around 70g as I do four doubles a day, each being 18.5g) means the beans will go stale faster.
Maybe if I seal the joint between the hopper and its cover and put some black paper around the hopper to protect the inside from light the beans will stay fresh longer? On the other hand its just a one day batch of coffee in there, so maybe Im overreacting?
I hope this will turn into an interesting conversation:)
Just about the hopper bit.
Air will still get in from the coffee exit chute through the burrs, unless you want to seal that up to and take it off for each time you grind.
This "popcornin" is most definitely real. It exists. Its a pain. The beans, having no weight on top of them, fall on to the spinning burrs and get tossed up into the air. They then fall onto the spinning burrs and get tossed up into the air. Etc.
But DSC, you are not leaving beans in there for days at a time to go stale. In your case, about 70 grams worth will disappear in one day.
I dont believe that beans are so fragile that, having survived in a one-way valve container for up to weeks, theyll suddenly go stale in a day in a hopper.
In any case, beans on the bottom will get little exposure to air as they are covered by their mates on top.
I wouldnt worry about it.
Ive got an EMO480 and I definately notice a significantly courser and uneven grind when there isnt enough beans in the hopper.
I have a glass thingy that I put inside the hopper to put weight on the beans/burrs when the hopper goes lower than about 1/2 full. Then, when the beans are so low that the glass jar cant do the job anymore (the "burr protector" gets in the way with the EMO480) I either romove and store the beans to use in a blend or throw another load of beans in.
Paul Bassett said that its important to "always keep the hopper FULL" to maintain weight on the burrs, which is a pretty tough ask if you trying differenct beans and origins. The glass weight hopefully simulates a full hopper. Does anyone else do this or something similar?
Disagree with Mr Bassetts advice -- would be more applicable in a commercial environment where they go through the hopper in
hours or even minutes.
Im wondering how the popcorning effects grind evenness. I understand that some of the beans jump when they hit the spinning burrs, but what is wrong with that? They can break into pieces, but still those pieces will be much bigger that the output of the grinder. They will still need to be grind into finer particles, plus that breakage still goes on when the bean gets between the burrs. I just cant understand whats so bad about the whole popcorning effect. Has anyone ever done any experiments that show the bad influence that popcorning has on the grind evenness?
Yup I agree with Robusto, a 100% full hopper is a good thing in commercial environment, but not in home applications.
Well, I must say I only notice the difference in the grind when the beans get REALLY low... as in, the last shot or two before my weight cant put any weight on the beans anymore.
Robusto, what makes you so confident in dismissing Lord Bassetts divinely inspired wisdom ;D? You didnt say why you disagree, you just that you disagreed. Just as a matter of interest that is.
Experiments are for labs...its known from experience
Cant that be somehow connected with the fact that the last beans of the present hopper batch are more stale than the rest? Of course thats only possible if you have a large amount of coffee in the hopper, like 90-100% full.Well, I must say I only notice the difference in the grind when the beans get REALLY low... as in, the last shot or two before my weight cant put any weight on the beans anymore.
Wushoes: I understand that you have experienced the effect of popcorning? if so what does it do? are the extractions faster? faster blonding?
Im still wondering how "jumping" beans can affect the grind evenness.
*hand shoots up*Has anyone ever done any experiments that show the bad influence that popcorning has on the grind evenness?
Firstly, Im going to presume that by "grind evenness" you mean "repeatability of particle size distribution spectrum." Thats because Im not aware of a skerrick of evidence that having a bunch of particles of exactly the same size is actually a good thing.
Basically, whilst experimenting with a bunch of different coffees during a Sunday arvo session at TMR, I was using a number of beans that we only had a few hundred grams of. Dosing the same way with the last shots resulted in a faster extraction. I havent done an experiment to see if that extraction speed is repeatable.
One of the internet coffee denizens who is famous for backing up his assertions with experiments is Jim Schulman. In doing an experiment to determine which of a set of conical grinders produced a better shot, he rigged up some small cylindrical paper hoppers for each grinder. He found that then weighing the beans down with a shot glass simulated the effect of a sufficiently full hopper. (BTW; the mazzer robur spanked the two macap conicals and the mazzer mini for normal doses of coffee.)
Im not sure that its the beans jumping around that matter. It could just be having less weight feeding the beans into the burrs.Im wondering how the popcorning effects grind evenness. I understand that some of the beans jump when they hit the spinning burrs, but what is wrong with that?
Yes, Id say that youre over reacting. If you manage your bean supply freshness it shouldnt be a problem. If your bags seal well, leaving the beans in the hopper might actually make it easier to keep your shots dialed in. At work, I have taken to cutting open bags for my shifts well in advance of using them (usually the night before). Otherwise, I have to chase the grind all over the place as the beans start to enjoy the ambient conditions more. Or whatever they do!Maybe if I seal the joint between the hopper and its cover and put some black paper around the hopper to protect the inside from light the beans will stay fresh longer? On the other hand its just a one day batch of coffee in there, so maybe Im overreacting?
Inspired by another recent post that touched on the popcorning issue, I did a little "amateur" experimenting over the weekend.
In my case, I dont use the hopper at all, and measure a double shot [volumetrically] and just drop it into the throat of the grinder.
I have looked for evidence of popcorning, and maybe one bean in 5 shots will jump, but otherwise it doesnt seem to be a real issue.
I have a flat burr grinder and the beans are flung centrifically into the burrs. As I see it, the spinning whirlpool seems to "hold" all the beans in place.
Also, in my grinder, the throat has a diameter of 50mm, and grind chamber is larger again so this too, may assist in keeping the beans down.
Over this weekend I tried several methods of weighting down the beans: upside down pullman tamper, cut down chair leg, plastic medicine bottle full of beans etc.
Strangely enough, the first two methods seemed to jam the beans, sometimes only 3/4 of the beans would grind through.
The med bottle method which approximated the "real weight" of more beans didnt jam but seemed to make no difference.
Specifically, I was looking for discernable changes in the grind texture and/or the extraction time and I saw no change.
Since I can get repeatable results with 18g of beans sitting by themselves in the hopper, Im happy to stick with this method!
I concede that different grinders and burr sets and even beans may behave differently, especially conical burr sets [like the sunbeam] that may rely more on gravity feed, than centrifugal force.
Also, I can understand that this issue would be more relevant in a commercial setting.
Bottom line, if you can get repeatable shots stick with your preferred method. ...as Luca says "IWITCTC"
Its not about grind evenness...you need a whole bunch of different sized particles to pack in...
Think of say....interstitial and/or substitutional atoms within a lattice for those who know chemistry (I dont know chem but know enough of it to make this analogy). Interstitial atoms fill up the gaps between the larger sized particles.
For some reason it screws up my pours like today when my hopper kept on getting empty when I was busy.
Im an advocate for keeping a hopper full of coffee....otherwise if you have a compulsion to weigh out beans and grind per shot like that, my advice is to take the hopper off pop your coffee in to the throat of the grinder and leave your tamper on top.
Spot on, Wushoes. Now that I think of it in terms of "interstitial and/or substitutional atoms" it all falls into place.....
This phenomenon doesnt seem to be an issue with the recently acquired LSM grinder. I only drop enough coffee into the hopper as required, either for two brews at a time or just one for me. The resulting grind is very noticeably uniform.... no large pieces and almost no fines at all. Theres probably more to this thing than meets the eye :-?, from one grinder to another.
No popcorn for me thanks ;),
so today I filled my hopper with around 80g of coffee and made two shots each with 18.5g. The results where quite different to what I usually get when weighing coffee per shot. I almost choked my machine two times and had to wait 20s each time before a steady stream of coffee appeared. Will check how it works with the next two shots that I plan to make later today, but Im expecting to see faster pours.
Anyway it all seems to be true:) and as Mal says it also depends on the grinder you use. I guess its best to try both weighing per shot and having a half full hopper to make sure.
I find small grinders (eg Sunbeam doserless) are effected more than the bigger ones (Mazzer)
I cant see how having one bean or a kilo of beans in the hopper would affect the grind size.
Surely that would be determined not by the weight of beans on the burrs, but the spacing of the burrs.
I reckon you could put some rice(got rice?):P into a greanbean bag and put it into a hopper and it will shape itself into the shape of the hopper and giving it weight, which hopefully doesnt get eaten up by the burrs. That shouldnt happen with the EM0480 though since it has a little cap thing. Havnt tried but it shouldnt...
Its interesting. It may be due to my poor technique - which in all honesty may be it! *shrugs*
HaHa. I dont know about divine inspiration. Im sure that his advice is good for his commercial environment where, as I said, theyll churn through a kilo of beans in no time. :DOriginally Posted by richy_4000 link=1184501068/0#6 date=1184504736
But for say, me, to use a kilo of beans would take about 2 weeks. I dont think having that many beans out of their air-tight container for two weeks is going to do them any good. :o
having the two grinders side by side on the bench, it has been interesting to observe the difference in the "pop corning"...
Rocky (without the finger guard) has virtually no jumpers, perhaps one every 5 or 6 seconds..... whereas Ms Carimali throws the beans around like there is no tomorrow!!
if i want to single-dose grind and operate Ms Carimali without the mini hopper i have to hold my hand on her throat to stop the beans from going everywhere and after grinding there will be a layer of coarsely broken beans sitting on the sloping-down part of the throat which needs to be wiped/pushed down into the burrs.
and, it may be my imagination, but when i pull shots using Ms Carimali s grinds "grinding through the doser" or from (inadvertently..) "the last beans in the mini hopper ", they seem to blond faster...
i am now making sure Ms Carimali always has a weight of beans on her throat. ;)
Considering the limited amount of coffee I drink at home ( one or two per day) this thread has made me think twice on upgrading from my handgrinder to something better, say an IBERITAL.
I like the fact I can grind small amounts of any particular bean or blend on a given day with minimal waste, and knowing that my different types of beans are hermetically stored until they are to be ground. I might not get the better crema I would only get with a finer grind, but that is made up for the nice little shots I currently get which are custom blended to suit my mercurial moods.
THe hand grinding is relaxing too without the shrill of the electic burr.
Hand grinding advocate, Jason
I generally have little trouble with pop corning with the Rocky grinder. So my hopper is always empty and I put in just enough beans to grind for the required number of coffees that Im making. I do notice the occasional bean jump around but it doesnt make any difference to my coffee. If anything, that very last bean thats hopping around will be just grind that I will throw away when I next make my coffee, as I always discard the first couple of seconds of old grind anyway.
Ive got an EM0480 and have also noticed that the more beans I have in the hopper, the more evenly and quicker the grinds seem to come out of the chute.
As Im the only coffee drinker in the house and I cant be bothered emptying the hopper each time after Ive used it, I just keep mine about a quarter fill and use my tamper as a weight on top of the beans. This seems to have the same effect as having the hopper full.
As Im usually grinding coffee both in the morning and once or twice in the evening, I figure that the beans arent being left out for too long to go stale. Once a week though, Ill empty it and give it a good clean.
Maybe "pop-corning", where it occurs, has more to do with the peripheral velocity of the rotating burr plate, the shape of the grinding chamber and the profile of the feed chute into the grinding chamber. As Lizzi has observed above, I too rarely noticed this phenomenon occurring with Rocky as I only ever load and grind the beans Im going to use immediately. It is more noticeable in the LSM grinder but the grind size is unaffected and as Robusto stated above, how could it anyway.... the burr-plate gap hasnt changed and thats the only way out for the beans.
Perhaps there is something more to this than any effect that pop-corning is being attributed with.... Yet another mystery ,
My view on this, based on observations of conical burs only, is that having a head on the beans at the burrs does have an impact on grind.
I suspect beans without a head bounce around much more and are more prone to being smashed, and/or, the beans are shaved thinner as the pressure between bean and burr is lower. Having a head pushing the beans against/through the burrs changes the grinding characteristics.
A very obvious example is when I grind using a Zass manual grinder, the last portion of the beans, without a head, hang up in the burrs, i.e. they do not feed through at all well, and tend to grind to dust. This is more due to the poor feeding characteristics (i.e. pressure from above), but I think the principle is the same.
As others have mentioned I perceive the grind to be better through the EM0480s, conical burrs if the hopper is loaded. Ive found I have to change the grind setting if I grind with just the required amount of beans. The result is still okay, but the characteristics of the grind certainly change.
Does anyone work in a lab that can do grist (sieve) analysis, I used to have access to this type of equipment...
From Robustos comments it looks as if the Iberital Challenge popcorns alot and is therefore not a good grinder if you want to feed small quantities of beans into to test blends etc ie hopperless use.
Does anyone disagree with this?
I was eyeing off the IC as a future grinder purchase and like to grind just enough beans each day rather than having a full hopper.
Beanhead, I disagree with your conclusion that the Iberital Challenge is not a good grinder.
It IS a good grinder in may respects. But even good grinders have shortcomings, irrespective of whether they use conical or flat burrs, cost $300 or $1300.
Others may disagree, but my experience over two years with this grinder is that you cannot feed in 20 grams of beans, and expect 20 grams of grounds in the basket.
Grounds get trapped and build up in the grinding chamber, clinging to areas where the sweeper does not reach.
And Im talking about a doserless here. Could be worse still with a doser
It can be messy. Very messy. If you stick to 14 grams in the basket, that is not an issue. But when you have to heap the basket to collapse and level, it is a big issue which is straining my maritial relationship (a little hyperbole here).
Popcorning? Yes, it does. But even the last stubborn bean will eventually succumb.
Now, these "problems" or "shortcomings" are not unique to the Iberital
And, they are quite unrelated to what really counts: the qualaity of grind.
On that score, a very important one, it is an excellent grinder.
Construction wise: It has conical burrs set in very robust plastic. Brass or bronze bush bearings . Reduction gearing to give it a slow speed so it maximises power and does not heat the beans.
If I were to upgrade -- and being me I am sure I will -- it will be for two reasons:
-to eliminate the mess (and save the marriage!)
-to get an easier mechanism for changing grind setting.
I am very, very happy to disagree with your comment ;DOriginally Posted by Beanhead link=1184501068/15#26 date=1187768230
Firstly, has anyone actually done any sort of experiment to prove the evils of letting your beans be exposed to the air for a few days? At work I usually like to cut the bags that I intend to use open a few hours or even the day before I intend to use them. This seems to stop me from having to change the grind as much. Competitors at barista competitions do the same thing.
I cant actually see where Robusto said that the Iberital popcorns a lot. And popcorns a lot relative to what, exactly? The throat that feeds the burrs is a good deal narrower than the throat on the mini. If anything, I would expect it to popcorn less than a grinder with a larger throat. However, the smaller throat means that if you want to physically remove the hopper there will not be enough space above the burrs for a whole double shot of beans.
As Robusto says, the Iberital certainly does have its shortcomings. But bottom line, it produces a very good cup at a very reasonable price point.
If you want a grinder that is designed to be used for grinding a single dose at a time, I suggest that you buy a Versalab M3 and put up with the potential durability issues that some of its users have flagged. If not, I really dont see whats so difficult about keeping a hundred grams of beans in the hopper at the time. If you want something that will be easy to change around for different beans, I suggest that you get something with a mazzer style grind adjustment (ie. stepless collar that allows wide movements easily) and a bean gate to close off the hopper.
Hope that helps,
Yes, Luca, the sliding gate for when the loaded hopper has to be removed -- forgot to mention that.
Its a nuisance to have to tip the whole grinder, hopper and all horizontly, to move the beans from the throat and into the top end so they dont spill out everywhere.
But again, while all these anciliary things make life easier, they have no bearing on the essential function of the machine: to produce quality grounds.
Remember, even if popcorning is occuring, and, if as a result, a different grind characteristic is produced to that of a full hopper, it is not necessarliy a bad thing.
Provided the "popcorned" grind produced is consistant between successive grinds, then adjustments could [actually would] be made to the grind setting to compensate.
I see popcorning as a problem, only if the popcorning produces variations, between each successive grind.
I have an MDF and in all honesty, it rarely popcorns. I couldnt really count hpw many times it happens, it is so rare.
I have loaded up my hopper with a lot of beans if I am grinding a heap of beans for OG to take to work every now and then and the MDF churns through them quickly. Not sure of the quality of the grind as this is usually for a plunger.
I honestly cannot see how the amount/weight etc of beans in the hopper is going to affect the grind as the weight of the beans on the burrs does not affect the function of the burrs.
Be honest with yoursves - Arent you all just being a bit anal about all this and need to take a reality check?
Originally Posted by lucinda link=1184501068/30#31 date=1187837113
Snigger! Hehe! ;D ;D Love the comment. :)
I guess if people were less than a perfectionist, wed have to start a new website called Coffee Slobs. :-X
I agree with Lucinda. There are quite a few other things that I can concern myself with before I would worry about this. If indeed I do perfect all the other "bigger" things that will improve my coffee making skills, Ill certainly look at this. And when I do, Ill hand-pick my beans and only use uniform sized batched, and slide them into the grinder one at a time, pointy end first!
I shut the hopper door and they cant bounce as high.
I leave the hopper door open so they can bounce higher! Wheeeee! ;DOriginally Posted by Thundergod link=1184501068/30#34 date=1187863402
"chuckle, chuckle" ... wouldnt mind seeing you do that, Dennis....Originally Posted by Dennis link=1184501068/30#33 date=1187860242
actually, the main reason i made the mini hoppers for Ms Carimali was the fact that i regularly forgot to put my hand over her throat and her bean-spitting behaviour had side effects... i kept grinding the beans into the carpet and the dogs found the beans i missed on the floor and ate them... caffeinated dogs... like having bouncy balloons on the very end of horizontal piece of string. :o
for my two cents worth,
using 4 grinders compak k8, k3touch,
la cimbali cadet and Fiorenzato T80 A,
inmho I have seen little or no variation when the bean level is low and
no discernible difference when a little pop corning takes place,
perhaps we should stick with the old
whats in the cup that counts theory
just me $1 worth,
did you see that? inflation and compound interest are a bugger of a thing when combined. ;D ::)
At least I know Im making good use of the plastic tamp that came with my machine...Fits perfectly in the throat of my Mazzer.