Some thoughts on dosing - Page 5

[Randy G.]

To summarize: Tim advocates finger strike levelling to the basket rim, with very careful dosing technique (no tapping or shaking) to avoid updosing. His dosing recipe results in "14 to 18 grams in a double basket depending on the coffee, grinder, and machine used." Not quite the same as Ken's "use 14g or less in every case" dose regimen.

I state that no one method can be universal. While Tim's method may work for grinder A used with machine B, attempting it with grinder C which may create a less-fluffy grind may cause an overdose because of the distance that the screen protrudes basket and the decreased compression of the coffee when tamped.. As a specific example, if you try that with a Rocky - Silvia combo you very likely will be over-dosing which will fracture the compacted coffee before the extraction begins.

The strike-off and tamp method is a good place to start, but the barista needs to make adjustments to the dose to meet the specific combination of coffee, grind, grinder, and machine design, and then make the fine adjustments to adjust the taste. I look suspiciously at an recommendation that implies or states "always" or "universal" application.

[GC7]

Thank you all for the replies. I guess my actions of bypassing the Silvia/Gaggia machine level right to QM Anita for an easier path to good espresso answered my own question but I do appreciate the explainations and mindsets from everyone.

[Ken Fox]

Well, unless you want to argue 15 grams isn't "Italianish" enough:

I went back and read the relevant part of your Cimbali Junior review, and gave a little thought to how our observations and dosing would have differed over time, and it obviously all comes down to basket choice and our varying experiences with different espresso machines over time.

I have been using a wide variety of different baskets, mostly aftermarket, especially in the last 10 years. Initially this came from my attempts to emulate what other online users were using during my "formative years" in being a home barista. The advocated procedure in online coffee (at least until recently) has been to follow what Schomer was advocating in his book, and what was done in the marquee cafes, e.g. to updose, distribute, and tamp like hell. There really was no other way of doing it that was given any credence on alt.coffee and coffeegeek (or even here, if one goes back more than a couple of years). The small double baskets that shipped with my original Vibe Junior would not hold 18g, and I obtained many other (mostly knockoff) baskets to allow me to use more coffee in the espresso making process.

My 13+ year old Vibe Junior S shipped with PF baskets very different than what shipped with the much newer rotary DT1. The older double basket was shallower, and I stopped using it perhaps as much as 10 years ago. The double basket that shipped with the newer machine was much deeper, and presumably that is the one that shipped with your review Junior from Chris. This basket (which I don't use) should easily accommodate more than 15g with tamping, although with no preinfusion will channel, as you observed.

More recently, I bought even more baskets as I looked for a way to visually dose in the range of 14g without resorting to a scale, but I found that every double basket I had or bought (trying to get shallower ones) would hold much more than 14g if filled to the rim, then tamped. Later, I threw in the towel on doing this visually when I concluded that weighing into a ramekin was both more repeatable, faster, and less messy than any of the other methods I'd tried.

I am not using OEM baskets; I think the ones I use now came from coffeeparts.com in Australia. They are the same baskets I used to dose 18 or 19g into.

I had many prior years experience using my old vibe Junior with an updosed/tamped basket and had no trouble with this, but when I switched to the rotary Junior I started to get channeling. I never considered changing my dosing, which I believe was pretty standard in online coffee, rather I put in a delay timer on the pump which made the rotary machine emulate the pressure profile of the old vibe machine, with its slow pressure ramp up. This eliminated my channeling problems and allowed me to continue to updose, which I did.

On the other hand, you, Dan, didn't have this prior experience with Cimbali Juniors and immediately noticed the channeling, correctly attributed it to dosing (at least in this stock machine with no preinfusion), and adjusted your dosing procedure. These are all part and parcel of the same issue, the pressure profile of the new Cimbali rotary Junior, which made no allowance for a slow pressure ramp up as had been present in earlier versions of their machines.

My opinion is that Cimbali has done a pretty poor job of changing over from their vibe pump era to the use of rotary pumps, at least in the Junior, and these problems could easily have been eliminated at the manufacturing level had they considered that at least some of their customers were going to dose higher than what they are accustomed to in Italy. This is not in my view an issue of the Cimbali grouphead or basket being intolerant of updosing, at least to 18 or 19g (what I used to use routinely). This is an issue of a poorly thought out changeover from vibe pump driven to rotary pump driven machines.

The above maybe explains the mechanical aspects of this but one is still left with the issue of taste and how much coffee one wishes to assault one's self with in one shot. Having spent years seeking the kind of taste profile one gets from "updosed" shots using blends designed to be updosed (all I drank for YEARS), there is no question in my mind what allows me to appreciate nuance in straight espresso, and that is by dosing at a much lower level, e.g. about 14g, and utilizing (mostly) fine single origins roasted lightly for the coffee.

Finally, I have never taken any credit for lower dosing being my idea, and have (repeatedly) attributed my own switch to lower dosing to conversations I've had with Jim Schulman and Aaron DeLazzer. I have had very few original ideas in the world of online coffee. My strength has been in challenging commonly held views and being willing to invest the time in trying to test them.

ken

[RapidCoffee (original poster)]

I had many prior years experience using my old vibe Junior with an updosed/tamped basket and had no trouble with this, but when I switched to the rotary Junior I started to get channeling. I never considered changing my dosing, which I believe was pretty standard in online coffee, rather I put in a delay timer on the pump which made the rotary machine emulate the pressure profile of the old vibe machine, with its slow pressure ramp up. This eliminated my channeling problems and allowed me to continue to updose, which I did.

FWIW, my recently acquired La Spaziale S1 is the original version. This machine has a rotary pump, a Spaziale (non-E61) grouphead, and no preinfusion. The 53mm double basket is slighter taller and considerably narrower than the 58mm standard found on most commercial machines. Version 2 of the S1 comes with programmable preinfusion. I considered ordering an aftermarket preinfusion device from Chris Coffee, but decided to give the machine a try in its stock configuration first. Any signs of channeling disappeared when I adjusted the pressure down to ~9 bars.

In general, I consider preinfusion to be a Good Thing. But no, I don't think it's essential with good technique, regardless of the type of pump. I owned a Rancilio L7 (single group commercial machine, rotary pump, Rancilio non-E61 grouphead, no preinfusion) before getting my Vetrano, and was able to pull fine shots. Elektra A3/T1 owners seem to love their machines, despite the lack of preinfusion. This suggests that preinfusion is not the only path to achieving a good pour on rotary pump machines. My recent experience with the S1 suggests that other factors come into play, most likely headspace, when you dose over 14g.

Finally, I have never taken any credit for lower dosing being my idea, and have (repeatedly) attributed my own switch to lower dosing to conversations I've had with Jim Schulman and Aaron DeLazzer. I have had very few original ideas in the world of online coffee. My strength has been in challenging commonly held views and being willing to invest the time in trying to test them.

Nonetheless, this is a major contribution, which I (for one) am glad to recognize.

[malachi]

Any signs of channeling disappeared when I adjusted the pressure down to ~9 bars.

For most coffees I tend to work with between 8.5 and 9 BAR.
I almost never exceed 9 BAR (by almost never I mean that I can't remember ever having done so but it's possible I have).