Controlling shot extraction pattern - Page 2

[Abe Carmeli]

final note - i think you might be getting fooled when comparing grinders. are you weighing your dose after you've dosed and distributed? if you're dosing by weight, that's the weight that matters.

No chance of that. A full leveled basket using the Mini, will be ~ 3-4 grams heavier than the same volume using the M3. The key then to succeed with downdosing using the Mini is coarse ground. That makes sense as coarse ground occupies more volume.

[malachi]

So you are weighing post distribution?

Cool.

Oh... one note... I'm not using a Mazzer. I'm using a re-badged DRM (not the dual conical/flat but their straight flat burr model).

[Abe Carmeli]

It's good to see you back in the game Chris. We missed you.

[HB]

An extraction pattern from the outside in (where the center of the basket is the last to saturate) is caused by what I call Schomer's Crater.

Barry mentioned earlier his preference for the stock La Marzocco cinch-waist double basket. I happen to have a couple lounging in the drawer, so the last few days I've used them instead of my usual rounded 18 gram Faema-style basket. I need more time to evaluate if there is a noteworthy difference in shot quality, but they do appear to extract more evenly. Instead of the initial "donut" extraction I see with the Faema basket, the LM double seems to favor a more evenly centered extraction. It may be my imagination, but the extraction also seems "tighter", i.e., the liquid spread across the bottom of the basket during the extraction is thinner and the surface of the crema is very glossy.

Anyway, without waxing too poetically on the merits of one basket over another, I posit that the difference you noted in extraction patterns may also be influenced by your preferred basket.

[malachi]

I vastly prefer the ridged LM basket (in other words, I'm on Barry's side here).
I know it's harder to work with - but the results seem better to me.

[AndyS]

When I watch the bottom of the basket during a shot, I can clearly see an extraction pattern. For the longest time it was from the basket outside perimeter to the center. No matter which tamper I used. This issue came up before, with no clear answer as to what is causing it.

Hi Abe:

First of all, I don't think think the initial donut extraction pattern is a problem; everyone knows that donuts go well with coffee.

Having uttered that pearl of wisdom, I agree with Dan, the LM ridged basket has less of a tendency to produce the initial donut.

With a ridgeless basket, there is another technique that you might try. As you know, the M3 grinder's distribution pattern leaves a shallow crater in the center of the basket. Don't go out of your way to fill it in. In other words, leave the center a little underdosed, tap the pf on the counter a couple times, then tamp. For me, this seems to leave the center of the basket a little "soft" and the pour begins more evenly with less of the donut effect. YMMV; the results of dose and tamp are very sensitive to subtle variations.

BTW, do the "hole in the middle" shots taste lousy to you, or do they just bug your visual sense?

[Abe Carmeli]

Hi Abe:

First of all, I don't think think the initial donut extraction pattern is a problem; everyone knows that donuts go well with coffee.

What Barista techniques can I use to get those with Krispy Kreem Filling?

With a ridgeless basket, there is another technique that you might try. As you know, the M3 grinder's distribution pattern leaves a shallow crater in the center of the basket. Don't go out of your way to fill it in. In other words, leave the center a little underdosed, tap the pf on the counter a couple times, then tamp. For me, this seems to leave the center of the basket a little "soft" and the pour begins more evenly with less of the donut effect. YMMV; the results of dose and tamp are very sensitive to subtle variations.

Yes, it is the point I've been making. Schomer's crater leaves the center more dense, hence the donut. With the M3, there isn't a problem as I mentioned in my previous post, since one does not need to create a crater to dose 15 grams. I was interested in producing the same even saturation result using the Mini, and 15 grams of coffee. Malachi came up with the answer on how to do that. As to the L/M basket, it is better in general when it comes to even saturation, however, if you use Schomer's technique and leave a crater you will still get the donut, though it will be less pronounced.

BTW, do the "hole in the middle" shots taste lousy to you, or do they just bug your visual sense?

It started with the visual. I was wondering if equal saturation will improve the taste. The donut shape can produce an excellent shot, however, I'm always looking for the next incremental improvement, and that looked like a promising lead. Bottom line, it is hard to do comparison shot tests, as no two shots are ever the same. In such cases I let time make the decision for me. I use one technique for a month then change to the other. At the changing point I should be able to notice a difference if there is one.

[barry]

I vastly prefer the ridged LM basket (in other words, I'm on Barry's side here).
I know it's harder to work with - but the results seem better to me.

i like 'em mainly because i find them easier to work with! it's easy to tell overdose and underdose; can't hook up into the group on the former, and a 58mm tamper scrapes the basket on the latter.

[jasonmolinari]

Looking at the Stockfleths' video, it looks like the rotation only levels the perimeter, and the center and excess coffee is still brushed off Schomer style...is that not the case?

jason

[malachi]

It's not a leveling technique - it's a distribution technique and it covers the entire surface.

The idea is that you rotate a pile of coffee in a circular pattern around a center point in the basket while applying downwards pressure.

[jasonmolinari]

My "distribution" leaves much to be desired, i've been just basically overfilling, and sweeping clean, trying to fill holes and gaps as i go with a straight edge. I'm not happy with it though.

So with Stockfleths', the area around the perimeter is being slightly compressed while the center is just levelled?

thanks
jason

[malachi]

No, it's all compressed.
The pile moves in a circle around the midpoint, but the finger provides pressure across the entire surface.