cannonfodder wrote:So if you are in a hurry and need to pull a second shot in rapid sequence, try raising the piston about half a stroke and unlock your portafilter, but please be cautious just in case.

D'oh! <insert sound of hand slapping forehead>

cannonfodder wrote:So if you are in a hurry and need to pull a second shot in rapid sequence, try raising the piston about half a stroke and unlock your portafilter, but please be cautious just in case.

Never thought of that way, but it seems so easy now that you mention it. I second that D'oh, Dan!

What I usually do to speed things up is slowly remove the pf, especially slowly when it is nearing the point that it will fall right out. I may hear some hissing and this may very well cause some coffee grinds to get up near the gasket, but it works. Besides I clean the group pretty thoroughly everyday, so the grounds aren't that big of a deal to me.

However I will definitely be trying your method in the morning.

Kaffee Bitte wrote:20-30 for a single pull producing a single shot, seems perfect. Are you really getting a double from one pull? In order to get a double I require two pulls (or near it at least).

20-30 seconds for a single pull normale double? I really think so, and the brew ratios support this. The taste is what I've come to expect from a normale (not a ristretto), perhaps a shade more intense.

Lower pressure Pavoni pulls feature less crema, and a flavor profile more reminiscent of strong coffee or AeroPress brew. They also have a markedly long finish, with a lovely coffee flavor that lingers on the tongue for several minutes. Higher pressure pulls are closer in taste to my pump machine espresso shots. Both are enjoyable in their own unique fashion.

OK I may be a bit dense. You mean a normale in flavor, not volume. Correct?

First, I'll say I don't subscribe to the light tamp theory. I've dabbled in it, but have not been satisfied. I do not agree with timo that a lightly-tamped puck is less prone to fracture during a second lever pull, in fact, I believe the opposite is true. I think a firmly tamped and well-polished puck resists being disturbed during a second or even third pull. The only evidence I can produce to support this, however, is two years of good-tasting multiple-pull results. The pucks from these pulls ALWAYS pop out of the basket in one complete piece, and are firm and evenly wetted.

John, because I see you quoted SH, I know you will be open to a well-reasoned argument. I had less success in taking a second pull on the LP than I do with my PV. I beleive this is because they produce more volume per pull than the PV, but they hold less coffee, a max of ~14g. This means a one-pull, 28 ml shot is right on. Its no surprise your second pull is dishwater, especially if each pull is 30 sec. Try extracting 40 ml from 14g on a pump machine, and the second half will likely be pretty bad.

Kaffee Bitte wrote:OK I may be a bit dense. You mean a normale in flavor, not volume. Correct?

Nope. As discussed a couple of pages back, I'm using AndyS's espresso brewing ratios as a more precise and repeatable definition. This is the ratio of coffee dose to liquid weight.

For example, this evening I reduced the dose slightly and coarsened up the grind, with the goal of achieving a ~15 second pull using ~30# of pressure on the Pavoni. I preinfused with the Fellini move prior to a single full stroke of the lever. This was the better of two pours:


13.2g coffee dose in the double basket, very light tamp


33.2g liquid weight

13.2 / 33.2 = 0.4, so this was a 40% brew ratio. That puts it on the borderline between a normale and a lungo. I didn't notice any obvious blonding, but the higher volume and lower brew ratio suggests a slight overextraction.

In general, the taste of these lower pressure shots is not as enjoyable to me as the higher pressure pulls I've been gravitating towards. YMMV.

peacecup wrote:First, I'll say I don't subscribe to the light tamp theory. I've dabbled in it, but have not been satisfied. I do not agree with timo that a lightly-tamped puck is less prone to fracture during a second lever pull, in fact, I believe the opposite is true. I think a firmly tamped and well-polished puck resists being disturbed during a second or even third pull. The only evidence I can produce to support this, however, is two years of good-tasting multiple-pull results. The pucks from these pulls ALWAYS pop out of the basket in one complete piece, and are firm and evenly wetted.

I'll offer yet another point of view (a la Chris Tacy): the tamp is relatively unimportant, compared to factors such as grind, dose, and distribution. I'm just not seeing huge differences associated with light vs. heavy tamping. Brew pressure (i.e., how hard you pull on a manual lever) does seem to make a significant difference, as does brew ratio (how much water you pass through the puck).

peacecup wrote:John, because I see you quoted SH, I know you will be open to a well-reasoned argument. I had less success in taking a second pull on the LP than I do with my PV. I beleive this is because they produce more volume per pull than the PV, but they hold less coffee, a max of ~14g. This means a one-pull, 28 ml shot is right on. Its no surprise your second pull is dishwater, especially if each pull is 30 sec. Try extracting 40 ml from 14g on a pump machine, and the second half will likely be pretty bad.

We agree completely on this point. As I stated a few posts back:

My conclusion: for La Pavoni, overextraction is a far bigger factor than tamp pressure when it comes to multiple pulls.

P.S. - Congrats on the new member of your herd! Sorry if I missed the original announcement.

RapidCoffee wrote:I'll question this conventional wisdom one last time, and then shut up. As I understand it, tamp pressure drops off drastically as depth increases in the puck. So the light vs. hard tamp really only impacts the top of the puck. After the grounds are infused with water from the first pull, they swell. At that point, how much difference does it make, whether the tamp was hard or light? It's possible that tamp pressure affects the first pull more than subsequent pulls.

Challenging accepted wisdom is what it's all about, right? I would not want either of us to shut up. But rather than say that a second pull on a lever machine produces "dishwater", you might have simply tried the light tamp several times yourself.

And by light, I mean VERY VERY lightly. Unless you're asking yourself, "He cannot mean this lightly?" you're tamping too hard. Fill the basket with finely ground coffee, level not heaped, and compact it no more than 6-8mm. Adjust grind finer if the first pull thins -- the flow of the first pull should remain very viscous for 10-12 seconds. You might get some blonding towards the end of the second pull. Again, adjust the grind a little finer till that does not happen for at least 20 seconds (10+10) into the extraction. My point is to keep the tamp a constant and adjust only the grind.

I believe this extreme lightness of tamp addresses your valid objection that the coffee becomes less and less compacted, the deeper you go in the basket. But a heavy tamp might well compact the upper half or two thirds of the coffee quite densely even if the bottommost region is still relatively porous. But a tamp so light that all it does is level the surface might compress the topmost sections of the coffee hardly at all. An exceptionally light tamp compresses the top region less than a heavy tamp compresses the bottom region.

RapidCoffee wrote:... The slightly greater volume in the second pull is probably due to fully infused grounds plus a few extra drops between pulls.

Tastewise, any subtle differences between hard and light tamps were subsumed by the gross differences between the first and second pulls.

With a very light tamp, "gross differences" between first and second pull become less pronounced. The yield of the latter stage of the extraction is a welcome addition to the normale or lungo cup. I agree with you that if you press a manual lever very hard to approach 9 bars, the benefits I am attributing to the light tamp are much diminished. But couple this very light tamp with reduced and tapering brew pressure (as is the case with the Lusso though not necessarily the case with a manual lever) and the "gross differences" are even further smoothed out.

Finally, to repeat myself, this difference between the early stage and latter stage of an espresso extraction is not particular to lever machines. To confirm, run the same test with your pump machine, dosed moderately, not overdosed. Updosing makes the latter stage extraction more like the early stage extraction.

Regards
Timo

peacecup wrote:First, I'll say I don't subscribe to the light tamp theory. I've dabbled in it, but have not been satisfied. I do not agree with timo that a lightly-tamped puck is less prone to fracture during a second lever pull, in fact, I believe the opposite is true. I think a firmly tamped and well-polished puck resists being disturbed during a second or even third pull. The only evidence I can produce to support this, however, is two years of good-tasting multiple-pull results. The pucks from these pulls ALWAYS pop out of the basket in one complete piece, and are firm and evenly wetted.

John, because I see you quoted SH, I know you will be open to a well-reasoned argument. I had less success in taking a second pull on the LP than I do with my PV. I beleive this is because they produce more volume per pull than the PV, but they hold less coffee, a max of ~14g. This means a one-pull, 28 ml shot is right on. Its no surprise your second pull is dishwater, especially if each pull is 30 sec. Try extracting 40 ml from 14g on a pump machine, and the second half will likely be pretty bad.

Peacecup, results will vary according to dose. I have been stressing moderate dosing, whereas you put as much coffee in your baskets as possible, and have even been known to balance Cirque-du-Soleil-style on your big toe atop the Export's piston rod, to express the coffee when the puck you created has been overly resistant.

Also, I suspect we mean different things by "fracture". A soupy puck cannot fracture as I use the term. The coffee medium is so deformable that gaps are filled. Whereas a rigid puck can develop cracks, or be subject to side-channeling.

Regards
Timo

timo888 wrote:Finally, to repeat myself, this difference between the early stage and latter stage of an espresso extraction is not particular to lever machines.

That's where we disagree, assuming you refer to lever espresso machines that require multiple pulls. Two lever pulls don't equal two halves of a continuous extraction. I agree your suggestions minimize the negative impact for the Lusso and thank you for pointing them out.