Why lever shots are better: A Theory

[Alchemist]

I have been thinking about this for some time. In general we all tend to agree that lever shots just have something that so many pump shots are missing.

A lot of focus and guessing has been tossed around about pressure profiles, how it is under user control, etc.

I have a different theory that popped into my head after a day of espresso pulls at a NW espresso jam. I think it may be that once you cock the shot you are into a static temperature system, so the intra-shot (I think that is the term I want [during the shot]) temperature is very stable. I have often heard that intra-shot temperature stability is critical for clarity of flavor, and by having an isolated water source, that is what we have with levers. Might also explain that many of us have found that one pull is the way to go. More than one pull and there goes your isolation.

Am I on to something or just blowing hot water

[hperry]

Assuming that the Scace device accurately reflects shot performance on the Termazona/Brugnetti the temperature starts considerably below the target at the beginning of pre-infusion, reaching the target temperature after approximately 15 seconds. It maintains target within 1 to 2 degrees for most of the 25 seconds of the pull, dropping off about 4 degrees at the very end. It is an HX, so may have different characteristics than some other levers.

Interestingly it does produce very good espresso, even at temperatures considerably lower (2 to 3 degrees), and with substantially more temperature variance, than would be considered optimal on a pump machine.

[timo888]

My theory is that manual-lever baristas are maintaining not constant brew pressure but flow rate. We adjust our pressure on the lever, sometimes subconsciously, to keep the flow going. Extraction quality is in the flow, not in the pressure.

Try pulling a few shots "blind" -- literally-- and see how well you do. Close your eyes as you pull. Maybe even stop your ears with wax, like the shipmates of Ulysses. I can hear a good pull.

Regards
Timo

[Alchemist]

My theory is that manual-lever baristas are maintaining not constant brew pressure but flow rate. We adjust our pressure on the lever, sometimes subconsciously, to keep the flow going. Extraction quality is in the flow, not in the pressure.

Try pulling a few shots "blind" -- literally-- and see how well you do. Close your eyes as you pull. Maybe even stop your ears with wax, like the shipmates of Ulysses. I can hear a good pull.

Regards
Timo

ah now, I have noticed that of other manual baristas, but I always go for constant pressure, not flow. Now I do agree that I can often hear a good pull.

[grong]

My theory is that manual-lever baristas are maintaining not constant brew pressure but flow rate. We adjust our pressure on the lever, sometimes subconsciously, to keep the flow going. Extraction quality is in the flow, not in the pressure.

Where does this leave the spring-driven lever's espresso, by comparison? How do results from a manual lever and spring lever differ, all else being equal?

[HB]

I have often heard that intra-shot temperature stability is critical for clarity of flavor, and by having an isolated water source, that is what we have with levers.

You lever guys need to get out more.

Another unique advantage of levers is their perfectly even water column of pressure from the get-go:



This most recently came up in the Buyer's Guide to the Elektra Microcasa Semiautomatica, appendix section Why is the Elektra Semiautomatica So Good?

The consensus of North American espresso experts since Schomer is that the quality of a machine is mostly determined by how stable and adjustable its temperature and pressure are. My experience with the Semiautomatica convinces me that this is not even close to the whole story. It is not particularly stable on temperature and way off on pressure, yet it produces shots that spank many machines with far better temperature and pressure performance.

<snip>

Lever machines have a similar straight down and wide water path and also produce ultra-clear shots despite non-existent temperature and pressure controls. Joel Klein, a friend of mine who owns a Brewtus and an Elektra Microcasa a Leva always insisted that it was the simple water path of the levers that made the Leva's shots taste so good. I think he's nearly right; groups perform better if the water enters straight down over the entire puck surface, rather than entering in a narrow area or oblique angle, then dispersing turbulently in the gap between the shower screen and puck.

The A3 research was equally puzzling for me. The thread Pressure profiles, preinfusion and the forgiveness factor was my first public musings on the subject. I'm still puzzled what is the numero ono factor contributing to exceptional espresso today, but that's OK, it keeps me interested.

[timo888]

My theory is that manual-lever baristas are maintaining not constant brew pressure but flow rate. We adjust our pressure on the lever, sometimes subconsciously, to keep the flow going. Extraction quality is in the flow, not in the pressure.

Where does this leave the spring-driven lever's espresso, by comparison? How do results from a manual lever and spring lever differ, all else being equal?

In a Peppina vs Caravel grudge match ...
-- both gravity-fed open-kettle temperature-stable machines
-- both give you control over the preinfusion
-- Peppina's spring is unforgiving: you either have a grind that is within the sweet range or you don't
-- Caravel you can finesse somewhat and compensate for too coarse a grind with a gentler pull, for too fine a grind with a harder pull, letting up, and then pulling again; too much unrelenting pressure stalls the flow (as Illy points out)

It's possible to pull excellent shots from both.

Easier to change beans on the Caravel with fewer sink-shots. Since you can compensate mid-pull on the Caravel, shots where the grind isn't dialed in yet are still drinkable.

The spring was better suited than a manual lever to a commercial establishment (or to entertaining dignitaries and such at home) because it left the barista's hands free to multi-task.

In terms of taste, the difference resides in constant pressure versus variable pressure. No matter how robot-like the manual-barista may think his technique is, the pressure will vary quite a bit. It can ramp up quickly or slowly, it can oscillate and falter -- all of which can be virtues or vices.

The manual lever is a stringed instrument without frets. The spring lever, one with frets.

Regards
Timo

[grong]

timo888,

Thanks for your lovely reply.

grong

[another_jim]

My theory is that manual-lever baristas are maintaining not constant brew pressure but flow rate. We adjust our pressure on the lever, sometimes subconsciously, to keep the flow going. Extraction quality is in the flow, not in the pressure.

This theory is still in the running. Andy found the best profiles from his within-shot pressure profiling system came from ones that came close to constant flow. However, the result wasn't better taste clarity, but much better mouthfeel. Since this tends to be a weak spot on levers; I'm not sure where we stand.

As Dan posted, I'm still scratching my head about how taste responds to extraction. There's a few simple ones like "if it's sour go hotter and slower, etc" but other than that, most of the the theories don't wash. I got two silvias for side by side tests, and a lot of food dye to get traces of water paths through the puck, but I've done absolutely nothing in the way of research. I'm still enjoying the shots from the Elektra too much to get all analytical.

[timo888]

. . . Andy found the best profiles from his within-shot pressure profiling system came from ones that came close to constant flow. However, the result wasn't better taste clarity, but much better mouthfeel. Since this tends to be a weak spot on levers; I'm not sure where we stand.
. . .

For clarity of delicate floral notes, the honors in my house must go to a Papua New Guinea roasted Full City pulled lungo and so gently on the Caravel it barely cleared the bar for espresso. It was the very opposite of mousse in the mouthfeel and the crema was not robust, but I was as high as a hummingbird on the first sip.

Regards
Timo

[Pixelator]

I have been thinking about this for some time. In general we all tend to agree that lever shots just have something that so many pump shots are missing.
[snip]

By "we" are you referring to espresso drinkers in general, or just those people who already own lever machines?

I ask this my question because I'm currently trying to decide on the type of machine to purchase as my first serious home unit. Emotionally, I've been seduced by what I've seen and read about the Micro Casa. I'm worried however about the concerns of too hot brewing temps after the first couple of doubles and my ability consistently achieve high quality results.

For not that much more money I can buy an Andreja Premium or step up to a Giotto. Aside from the physical act of pulling the shots, what would be "missing" from shots made using these two machines that is present in shots from a lever machine? Thanks for any insight you are willing to share.

[hperry]

By "we" are you referring to espresso drinkers in general, or just those people who already own lever machines?

I'm worried however about the concerns of too hot brewing temps after the first couple of doubles and my ability consistently achieve high quality results.

There are multiple discussions within the lever forum that contain information about the differences between levers and pump machines, although somewhat surprisingly I couldn't find in a quick review much beyond this thread where there is a systematic discussion. Owning both, I am able to obtain a richer, fuller bodied shot with less variation shot-to-shot on the commercial lever than with any other machine I have owned. The spring-loaded commercial machine is less "fussy" about producing a good shot. Concentration on grind, distribution, simple temperature control, and to a lesser extent tamp are most of what you have to do to get consistently satisfying shots. Rather solid used commercial levers are found quite frequently for no more than a low to mid-range HX. More variability is introduced with home lever machines when you add major temperature control issues and finding a consistent pressure with which to brew (my experience with the Cremina). It is worth following the current thread on the Gaggia Achille, which seems to suggest that it overcomes the heat problem with small levers fairly handily - although maintaining repeatable pressure would, I assume, still be an issue.

[grong]

Aside from the physical act of pulling the shots, what would be "missing" from shots made using these two machines that is present in shots from a lever machine? Thanks for any insight you are willing to share.

In my view, lever shots are not definitively better than pump shots, but they are different. The people who sold me my lever machine say that you can get the same flavors out of either machine, but that the lever machine produces a softer shot. I think this is an excellent description.

My lever machine is more forgiving in producing a nice, enjoyable shot, and the entire experience, start to finish, is so smooth and quiet. It is very easy to get an excellent extraction from the lever machine, without any blonding.

Some days, I feel like something wild, and that is what I get from my vibe pump machine--explosive crema, supernatural syrupy flavor, and more volume, super extracted from 19 grams of coffee. It is delicious, somewhat noisy, and followed by backflushing--vrrrmp, bink, burp.

By comparison, a single shot pulled on the lever machine can be so silky smooth, elegant, and quietly satisfying. Softer, by comparison, really addressing a quieter mood, and normally what I prefer.

[Pixelator]

Thanks for both of your replies, HP and Grong.

Grong, my question to you is which commercial lever do you have? Where is a good source to start looking for a used commercial machine, and will it fit on the kitchen counter?

After checking in here I'm feeling more comfortable with the idea of a lever.

[grong]

Pixelator,

I have a Ponte Vecchio Lusso, a residential machine, and I find it suitable for my domestic situation, making espressos and cappuccinos for one to four people. I have had it only three months, but I have had pump machines for about 20 years. I always thought I would love a lever machine, and I finally got around to it. People on this site have helped me make the match a success.

Moschetti.com in Vallejo, CA, has a Conti Prestina, completely refurbished. It is a direct plumbed unit with auto boiler refill. I am not sure how it would fit in your cabinet scheme.

Best of luck to you in finding the machine of your dreams.

[hperry]

After checking in here I'm feeling more comfortable with the idea of a lever.

Although you didn't specifically ask , if I were looking for a lever in the home market I'd carefully follow the Gaggia Achille thread on this site, and also take a look at the Ponte Vecchio Lusso. I've been pleased with shots from the Ponte Vecchio and am fascinated with the discussion of the Achille, which seems to overcome many of my objections to home levers. The Lusso is spring loaded, the Achille uses your own arm pressure to produce the shot. The Ponte Vecchio has a bigger heat sink than most and it doesn't get overheated as soon as a Cremina. From the review, it appears that the Achille largely overcomes overheating as a problem.

It might be worth asking Dr. Jim what he would recommend in a commercial machine, as he is an encyclopedia of knowledge re: commercial levers.

[Pixelator]

I never suspected that this research would so thoroughly consume my time! Even though the Conti looks too "commercial" for our kitchen, I think I might drop by Moschetti to see if they will let me sample a shot from a lever.

I like what I see in the Ponte Vecchio Lusso and the price seems reasonable. My only reservations are that I can only find one place that sells them in the U.S. and I haven't heard of these machines before. Do they have a decent track record with regard to dependability? Oh, and who would repair them, anyone generically qualified to work on espresso machines?

[grong]

I never suspected that this research would so thoroughly consume my time! Shocked Even though the Conti looks too "commercial" for our kitchen, I think I might drop by Moschetti to see if they will let me sample a shot from a lever.

I like what I see in the Ponte Vecchio Lusso and the price seems reasonable. My only reservations are that I can only find one place that sells them in the U.S. and I haven't heard of these machines before. Do they have a decent track record with regard to dependability? Oh, and who would repair them, anyone generically qualified to work on espresso machines?

Lost of good information on this forum, which can give you a good idea of what you can expect from a machine, before you buy!

As for Ponte Vecchio, I suggest in addition to reading what you want to about it, call and speak with Gene at Vanelis, in Rocklin CA. He is knowledgeable and straightforward. He can give you some solid information, and his shop works on PVs.

As for Moschetti, call ahead. They will probably have to set the machine up, which they will probably gladly do, in addition to setting you up with a grinder. Better bring a pound of beans! They might even have something else of interest that is not posted.

Best wishes.

[cannonfodder]

I am somewhat bias on the Achille because I am doing the review; however I can say without a doubt that the cup blows away the Gaggia Factory (La Pavoni). Dan's initial thoughts are that that is outperforms the Elektra and pulls as good or slightly better shots than the Cremina and that is with only two days of usage under the belt. Considering the Cremina is selling for around $3300 new and the Achille is $1200 new, and the Achille will pull shots all day without overheating, I know which one I would get.

[hperry]

I like what I see in the Ponte Vecchio Lusso and the price seems reasonable. My only reservations are that I can only find one place that sells them in the U.S. and I haven't heard of these machines before. Do they have a decent track record with regard to dependability? Oh, and who would repair them, anyone generically qualified to work on espresso machines?

Actually are many sources. One, which has sold the same machine under several names is:

The Good Coffee Company
818 Post Ave
Seattle, WA 98104
(206) 622-5602

They also repair them.

While I really like the Ponte Vecchio, I'd urge you to give serious consideration to the Achille and follow the ongoing review on this site carefully. The reviewer, who I really respect, gives it very high marks. I'm guessing, based on the review, that it will perform beyond the Ponte Vecchio and do equal or better than the Cremina - without the Cremina overheating problems. I wouldn't be deterred by the additional cost, based on the review (in progress).