Problem with channeling? Dose less and grind finer - Page 2

#11: Post by **another_jim** » January 5th, 2009, 7:48 pm

In connection with getting espresso close to brewed coffee taste ...

RapidCoffee wrote:Presumably you've experimented with lowered brew pressures? Using light pressure on a lever, I get a shot with the taste profile of strong coffee rather than espresso.

6 to 7 bar helps somewhat, but mouthfeel and crema take a hit at that pressure.

I personally think of all the variables, dose makes the biggest difference to the taste. But I have the sneaky suspicion that dosing changes really affect the first few seconds of the shot, before the coffee particles expand and the puck locks up. In effect, I think:

dosing changes --> fines migration and particle packing changes --> extraction changes.

Good grinders and competent distribution also count in this. But I'm thinking this is more than just avoiding uneven distribution and channeling. I think the way the particles interlock, the brickwork pattern of the puck, so to speak, has a number of basic variations. Dose, head design, grinder, and packing all determine which packing variant is predominant and how uniform it is across the puck.

A god shot may be the result of a crystalline god puck, i.e. a nicely regular packing of coffee particles.

#12: Post by **malachi** » January 5th, 2009, 9:11 pm

As has been said in the past - the goal of distribution is to create an even bedding of coffee.

January 5th, 2009, 9:57 pm

It seems as though it might be more accurate to say that the goal of distribution is to arrange the coffee grinds such that they extract evenly on the machine you are brewing them on. I am not sure this is necessarily an even bedding of coffee. I assume it depends on the flow characteristics of your grouphead. Going from an E61 to an Elektra T1 this week has been a real eye-opener: the distribution technique that gets me perfect pours on my Quickmill Vetrano gets me shots that start out as donut extractions, though they seem to recover and even out after ~5 seconds. Modifying my technique to increase the density near the edges of the basket seems to correct this aberration.

January 5th, 2009, 11:16 pm

Here's my summary statement on this whole thread:

Buy yourself a large conical or Cimbali Max grinder, and combine it with a basic, vibe pump driven, E61 espresso machine. Use good and fresh coffee that you like. Dose on the low side (~14g). Figure out a flush regimen that gives you repeatable shot temperatures at an extraction temperature you like.

This combination will give you a very forgiving setup, benefiting from excellent grind quality and slow pressure ramp up (e.g. "poor man's preinfusion") that will, with minimal effort, produce shots that rival the best that you can get anywhere.

ken

#15: Post by **Theodore** » January 6th, 2009, 4:42 am

HB wrote:
Yes, for some espresso machines - perhaps most - it indeed helps quite a bit. I assume the main advantage of dosing standard amounts (~14 grams for most espresso machines) is the proper headspace it affords, space that is eliminated if one doses more. This gap between the puck and dispersion screen allows for water to flow more evenly prior to full pressurization, potentially closing fissures as the puck expands. The same benefit can be had by using a deeper basket. For example, the so-called Synesso baskets easily hold 20 grams of coffee, but dosing them at 18 grams will allow for lots of headspace and it should help with the evenness of the extraction. Dosing a triple basket at double+ doses will leave tons of headspace, if you want to experiment with the tactile/taste profile at larger doses.

But if I use bigger baskets, as I have,16g,18g,and 21g,as well as 14g?

#16: Post by **peacecup** » January 6th, 2009, 4:57 am

shadowfax wrote:It seems as though it might be more accurate to say that the goal of distribution is to arrange the coffee grinds such that they extract evenly on the machine you are brewing them on.

This is a scientifically-sound hypothesis, and may be counter-intuitive to some. Assuming that a perfectly-even grind (and distribution) would result in a perfect extraction is a tempting, but probably wrong, assumption. Unless the coffee was distributed in a one-particle layer across a very broad and flat "basket", and subjected to perfectly uniform flow. Even the the bottom of the particle would extract differently than would the top.

So, as usual, Jim is probably correct is stating that one should match the equipment to the desired espresso.

PC

#17: Post by **peacecup** » January 6th, 2009, 4:59 am

Buy yourself a large conical or Cimbali Max grinder, and combine it with a basic, vibe pump driven, E61 espresso machine.

Or a 50-year old home lever and a conical burr hand grinder, which will also:

give you a very forgiving setup, benefiting from excellent grind quality and slow pressure ramp up (e.g. "poor man's preinfusion") that will, with minimal effort, produce shots that rival the best that you can get anywhere.

PC

#18: Post by **AndyS** » January 6th, 2009, 6:25 am

Ken Fox wrote:Here's my summary statement on this whole thread

No one who's followed this would say your summary is about the whole thread. It's simply a rehash of the posts that you choose to embrace.

January 6th, 2009, 9:59 am

OK, well how about this version?

Consult your banker, then have 3 phase power brought into your home, buy a 3 phase Robur, and a Speedster, and all will be well except perhaps your wife will divorce you and the house will be foreclosed?

ken

#20: Post by **AndyS** » January 6th, 2009, 7:50 pm

Ken Fox wrote:Consult your banker, then have 3 phase power brought into your home, buy a 3 phase Robur, and a Speedster, and all will be well except perhaps your wife will divorce you and the house will be foreclosed?

1. Banker is in NYC, trying to get his money back from Bernie Madoff.
2. Don't need 3 phase brought in, frequency drive synthesizes it from single phase.
3. Robur and Speedster, now you're talking!
4. Don't have wife: like you, I sleep with dog.
5. Keeping my fingers crossed on foreclosure.

But seriously, my criticism of your "thread summary" is that it ignores the point that Chris, Jim, and others have made: there are other styles of espresso that cannot be prepared following your formula.