Can fines migration be lessened with a tamp from hell?

[Elbasso]

Wouldn't tamping as hard as you can while also twisting left and right kinda lock the fines in between the bigger particles?

After testing with this myself I clearly noticed a more even extraction and less fines ending up in the cup. To me this seems to point to lesser fines migration than before. The twisting under pressure is usually considered a no-go but it doesn't seem to influence the seal at the perimeter of the basket. This could however be attributed to the C-flat base Reg Barber that I am using (see below). Or maybe the puck is so solid that the seal doesn't suffer from the twisting? Whatever it is, tamping like a madman does it for me

[RapidCoffee]

Wouldn't tamping as hard as you can while also twisting left and right kinda lock the fines in between the bigger particles?

After testing with this myself I clearly noticed a more even extraction and less fines ending up in the cup. To me this seems to point to lesser fines migration than before.

To answer one question with another: why would you want to do this? Fines migration is a critical part of brewing espresso.

The twisting under pressure is usually considered a no-go but it doesn't seem to influence the seal at the perimeter of the basket. This could however be attributed to the C-flat base Reg Barber that I am using (see below). Or maybe the puck is so solid that the seal doesn't suffer from the twisting? Whatever it is, tamping like a madman does it for me

There are many ways to make a fine cup of espresso. But any technique that potentially breaks the seal between the puck and the basket sides (tapping, polishing under pressure) is hard to recommend. It's possible that the twisting produces a better distribution, and you are resealing by "tamping like a madman".

Hey, if it works for you, go for it. But for consistency, I prefer to focus on grind, dose and distribution rather than tamp. If you get those right, any reasonable tamping style seems to work just fine.

[Elbasso]

Fines migration is a critical part of brewing espresso.

Aha! I totally misunderstood that. After reading about frontloading baskets due to vigorous WDT stirring or use of dental vibrator thingies, I assumed the migration to be a bad thing. I read that Scott Rao's book goes into the migration to some extend. I cannot wait for it to arrive.

Thanks for the insight,

Bas

[cafeIKE]

Some extra reading until your book arrives

Some Aspects of Espresso Extraction by Jim Schulman

Lattice Boltzmann model for coffee percolation

[Randy G.]

........Whatever it is, tamping like a madman does it for me

If you have to tamp that hard you are compensating for other problems. These MAY include:

- coffee that is old or over-roasted and creates too much dust
- worn burrs, worn grinder bearings, or other grinder difficulties that create too much dust
- grinding too coarse
- over-dosing
- poor distribution
- worm or low-tolerance basket
- brew pressure too high
- poor distribution of water from brewhead

[Elbasso]

Some extra reading until your book arrives

Good! I was almost afraid wasn't anything left to read about coffee (There's really no end to it, is there?)

worn burrs, worn grinder bearings, or other grinder difficulties that create too much dust

That one has been bugging me for a while. How do you diagnose worn burrs? I clean my Mazzer every two months or so and things look pretty "sharp". It's only one and a half years old and I use about 250gr a week so in theory the burrs should have a lot of mileage left.

[Randy G.]

How CAN you tell if the burrs are worn? Good question. In the 7 years I owned a Rocky I changed the burrs twice, and although the last set was still good for most brewing methods, for espresso use they were about ready for another change. How could I tell? The first change was done because over time I had ground some chunks of concrete that was included in some Yemen Moka I was getting (it was worth it). After the change I could tell the difference right away in the cup. Three sets, 7 years: 2 years 4 months per set... That was about 100 pounds per set on a very rough estimate. The burrs were still good, but not for espresso, all FWIW. All burrsets were genuine Rancilio, but I was not all that impressed with their hardness or ability to hold an edge. At $160/set I will probably not be in such a hurry to change the burrs in my Kony!

[CoffeeOwl]

Poor distribution of water from brewhead - due to lack of cleaning?

[HB]

Wouldn't tamping as hard as you can while also twisting left and right kinda lock the fines in between the bigger particles?

I don't know, I have never tried twisting under pressure, if only because it's hard to tamp evenly and likely to break the puck/basket adhesion, leading to side channeling.

My purely unscientific guess is that hard tamping doesn't do diddly with respect to the particles "locking" together, but can slow early wetting of the puck prior to pressurization. That is, the slower passive preinfusion gives the upper layer of coffee more time to expand, thereby acting as a more effective barrier when pressurization does occur. Whether delaying percolation for a moment is a good or bad thing is an entirely different question. I only tamp significantly harder when the pour is too fast and I don't have time for a proper adjustment, a sort of lazy man's two millimeter finer adjustment.

[Elbasso]

Thanks for all the replies guys.

The reason for me to start wondering about fines is that my shots seem to be on the short side. Less than 1,2 oz in 25 sec for a 14,5gr double. They taste and look pretty good. The naked extraction looks very even (beads form after about 8 seconds) but just seems to lose it's cohesion about 15 seconds after that. It just goes blond in an instant. It really looks like one of the videos that Dan posted with a front loaded basket extraction.

Tightening the grind just leads to even less volume in the cup and it still goes totally blond at around the 25sec mark. I am pretty sure that I've got all other facets (freshness, distribution, cleanliness etc.) under control. Still, only the tamp from hell allows me to get a 30+ sec ristretto with gradual blonding.

Gonna try to borrow a friend's grinder and see if it makes a difference.

[cannonfodder]

Stale coffee, or overly fresh coffee will do what you are describing. It could also be channeling in the puck but you should notice that in the taste. It will be weak and bitter.