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Manual versus Automatic Profiling

People who want manual shot profiling have many choices, from manual levers to Stradas and Slayers. The Bianca may well be most controllable and flexible of these choices; and that makes it well worth considering for those who want to do shot profiling. But what about the whole choice between manual and automatic profiling? Levers and other manual profiling choices became popular again because there were no good choices for automatic profiling; now that there are, will the manual machines become obsolete again?

I think there are two considerations. The first is that the automatic profilers have a way to go; the second is that there may be no real niche, either in cafes or for amateurs, for automatic profiling machines, once conventional ones have long, programmable preinfusions.

First, the remaining kinks in automation: Flow profiling has two phases, a long preinfusion where there is no flow; and a later part where the coffee is flowing. The automation for the preinfusion phase is fine -- a certain amount of time at a certain pressure is exactly what is needed. But in the flow phase, you want to do two things: manipulate the flow rate, not the pressure, and calibrate it not by time but by the weight in the cup. The DE1 can do this in advanced mode, but all the other machines have a way to go. Googling the topic will show that most experts agree with this.

This kink will probably be solved very soon, and existing autoprofilers will probably be upgradeable. So what happens to manual profiling then? Let's start at a café, and then go on to hobbyists.

In a third wave cafe, there will be a brew bar with a barista making pourovers, and an espresso bar with several baristas making mostly milk drinks. Should the latte machine be making 90 seconds profile shots? Of course not. The only ergonomically sane place for the straight espresso shots, especially when profiled, is at the brew bar. Have your latte blend at the latte bar, set up on a preloaded, preset grinder. Have the profiling machine and single dose grinder at the brew bar, and charge an arm and a leg for making profiled straight shots from any roast in the house. And in that case, what sort of machine? Obviously a manual profiler: either a sexy lever or a do everything paddle machine. The distinction between espresso and brewed coffee is obsolete; in the current high end cafes, the distinction is between custom and ready made drinks.

So where are the hobbyists, at the ready made bar or the custom bar? It's not a trick question, just a really obvious one.

All in all, I don't see manual profiling machines becoming obsolete any time soon.

Quasi-Brewing



I'm not sure if this is qualifies for the "stupid Bianca tricks" or the "for real" category, ask me again in a few months; but the Bianca can do any coffee at any grind and at any brew ratio.

For the French Press grind, I preinfused for 90 seconds with the paddle almost all the way off, so that the portafilter was at a very slow drip. After that, I ran up the weight to 100 grams in abut 25 seconds. The manometer showed no pressure, since the grind has no real resistance to flow. The taste was very much like that from my clever dripper (my favorite for French Press grind). I experimented with 60 seconds and 120 second preinfusions; to my taste the first was too delicate, while the second had a slightly bitter tinge. This may vary from coffee to coffee and palate to palate.

For the Turkish grind, I preinfused for 20 seconds, again at a slow drip, with the pressure reading around 2.5 bar. Then I maxed it out to 10 bar to finish the shot at 50 grams in another 40 seconds. I experimented with preinfusions of various lengths -- longer ones do not get bitter, but lead to more focused, intenser flavors with lighter mouthfeels that work better at higher brew ratios (the effect is hard to describe, I'm reaching a little). The brew is unique, not like a traditional demitasse or mocha pot, but clearer and more delicate. However, this may be a function of the very light roast.

Neither cup had light roast grassiness, which was apparent in the conventionally made shots from this coffee. Tasting side by side, it was apparent that the two brews came from the same coffee. The smell was the same. The taste difference was analogous to hearing the same notes played with different instruments at different tempos.

The Bianca for Espresso Newbies and Intermediates

First off, congratulations: you've bought a high quality machine that will take you from first steps to the leading edge of espresso. Most of the previous posts have assumed that Bianca buyers are people who've had lots of espresso machines, and are up on all the on-line discussions of pressure profiling. But there's always the all-in people who walk past the kiddie pool and jump right into the deep end. This post is for you.

There are three sections. The first is about using the Bianca as a straight forward E61 espresso machine. The second is using the paddle to emulate classic lever machine shots. The third is about more extreme pressure profiling that creates drinks that are something new, no longer akin to conventional espresso.


Conventional Espresso

The Bianca can be used like a conventional E61 machine, if you leave the paddle unused, all the way to the right. The display turns into a shot timer, and a bottomless portafilter is part of the kit. Get good at making shots that take about 8 to 10 seconds before the first drops emerge, and another 20 seconds of flow to make a standard espresso (about 1.5 ounces volume or 30 grams weight for the double basket).

Once your mechanics are sound; experiment with different combinations of finer grind/lower dose weight or coarser grinds/higher dose weight until you become proficient at making all these combinations. Note the difference in espresso taste. For most people, using most coffees, finer grinds and lower doses lead to a softer tasting shot; and higher doses with coarser grinds lead to a punchier tasting shot.

Finally, when your shot making mechanics are sound at different grinds and doses; experiment with different temperature settings. For most people and most coffees, lower temperatures lead to a more acidic balance, while higher temperatures lead to a more bitter balance.

This is the learning curve for people first using a high quality conventional espresso machine. It is by far the most difficult step of the three, since you are learning all the barista skills. Once you have these skills, you will be able to make really fine shots on just about any kind of machine with only a little more practice.


Lever Style Espresso

Working with grind/dose and temperature variations on a conventional espresso machine runs into limits. Coffees from Central America and East Africa, especially roasted light, have been treasured for regular brewed coffee since the early 20th century. However, these are often too intense and acidic for classic espresso, even if you use a fine grind and a high water temperature. Lever users noticed that they could make concentrated espresso shots from these acidic coffees that were much better balanced. Similarly, very dark roasts could be pulled with creamy tobacco and dark caramel tastes and no bitterness. Bottom line, levers can make good shots from a wider range of coffees, including those that are challenging on regular espresso machines.

So how does this work? When you pull down a spring lever, the water seeps int the puck at a pressure of 1 to 3 bar. And baristas can maintain this for as long as they want. Then when the lever is engaged, the pressure goes up to 8 to 9 bar, then declines as the spring stretches out, keeping the flow steady and maximizing the extraction.

The exact same thing can be done on the Bianca with somewhat less effort than on a lever. Grind your coffee a little finer, and dose a little higher. When you start the shot, move your paddle to the left, keeping the pressure at about 2 bars for about 20 to 25 seconds. Then finish the shot by moving the paddle to the right, to about 8 bar, and slowly letting the pressure drop and the flow slow down, so you have a normal sized espresso in another 25 to 40 seconds.

Try the same coffee done this way compared to the normal E61 style. For most people, when using regular espresso blends at medium roasts, the regular shots will have a small edge in creamy mouthfeel. But the lever shots will have the clear edge for both lighter or darker roasts, due to a more balanced taste.


"Brewed Shots"

Variable pressure machines like the Bianca can be used to make shots from any grind going from ultrafine Turkish powder to ultracoarse French press pebbles, and at any shot volume from the traditional ounce or two, up to four or six ounce shots. These shots may use preinfusions that last up to 90 seconds and shots that go on for several minutes.

The mechanics of making these shots is not a problem on the Bianca. Decide on a brew recipe -- coffee grind and dose, preinfusion time, shot time, and shot weight -- then work the paddle so the preinfusion has a very slow drip of coffee from the portafilter into the cup, and the flow portion gets to the right weight in the right time. It's a whole lot easier than learning how to make properly flowing shot at different dose and grind combos on a pump machine (the first step in this guide).

The problem is figuring out what brew recipes to use and why. And the answer is ... welcome to the bleeding edge. This stuff is still way up in the air.

My rough take so far, very unproven, is that there are two kinds of recipe.

The first is to use very fine Turkish grinds with very long preinfusions and brew ratios of about 2 to 3 parts water to 1 part coffee. When this is done with very light roasted "3rd wave coffee" the flavors that are separate in a regular brew, and unpalatable in any kind of regular or lever espresso, fuse into a single complex flavor. Getting this just right is a sort of 3rd wave holy grail.

The second is to use the Bianca as a high tech brewer. Use longer preinfusions for coarser grinds, shorter ones for finer grinds (as if you were steeping the coffee in a french press), and then go for demi-tasse brew ratios of 1 part coffee to 4 to 8 parts water. If you get this right, you will get the clarity, balance, and definition of brewed coffee, but at higher concentrations than conventional brewers.

However, this is so new that you should experiment for yourself. A major attraction of the Bianca is that you can make any ridiculous mad scientist shot that comes into your mind. The Bianca is the dream espresso machine for experimenters and brainstormers.

Using the Programmable Preinfusion

Don't; or mostly don't. If you want a classic E61 shot, the best approach is to set your paddle to about 60% to 70%. This will get you the signature 8 to 10 second ramp up to full pressure. If you want to do a long preinfusion with a very fine grind, using the paddle to keep the pressure at 2 to 3 bar wile the pump is running is your best course of action.

But ... if you want to make very fine grind shots without attending to the machine, the programmable preinfusion will work. The programming turns the pump on for a short amount of time to let water into the puck, then turns it off for longer amount of time to let the puck soak, then turns it back on for normal operation. The initial on and off time can be programmed.

Use 5 seconds on and the full 20 seconds off to preinfuse a fine grind properly. The pressure will rise to about 3 - 4 bar, then drop back to about 2.5 when the pump shuts off. This is the pressure required for a fine grind preinfusion. 20 seconds is the minimum time needed to soften the puck, so that the subsequent shot will flow rather than choke or drip.

Thanks to Graham for posting the Innards of the Paddle Group:



Take note of his warning:

Graham J wrote:I'd advise measuring outlet water flow at operating temperature, before removing the paddle and opening the valve assembly. I had a graph of flow from the group at 6 points of paddle position, posted elsewhere on H-B,but four measurement points will be enough. You'll need this data to return your paddle to its previous flow set points. One spline change can make a 5-10% difference in flow rate.

Lelit Bianca versus Bezzera Strega, Round 1:

This was like a chess world championship, mostly draws, with the wins coming from tiny differences in the shots.

I did 23 paired shots over the past weeks, pulled about 2 minutes apart, not tasted blind. The shots were ground, dosed, basketed, and prepped identically. After doing this series, I figured the pattern would hold for me no matter how long I went on, and stopped. I'll do a round two with anyone interested at the next get together.

Of the 23, 9 shots were indistinguishable, another 5 were draws where the shots tasted different but I liked them about the same, and of the 9 wins, the Bianca went 6 to 3.

Oddly enough, all 6 pairs of the turkish grind shots tasted identical. I used 1:2 brew ratio shots of very light roasts, with 30 second peinfusions; that is, poster child profiling shots. As far as I can tell, levers do these shots just as well as profiling machines. If you want to specialize on these shots, spend your money on a really good Turkish grinder* and use any machine that can do arbitrarily long 2-3 bar preinfusions and arbitrarily long shots without overheating (on a sipper, raise the lever to about 7:30 to 8 o clock, and hold). I gave up comparing this style shot after this string of draws.

On conventional shots, the Bianca mostly had a small edge on body, and the Strega, on flavor clarity, leading to a tie. But the Bianca won more often by equaling the Strega on clarity and beating it on body than the Strega won by beating the Bianca on clarity and equaling its body. Three of these shots were indistinguishable.

A caveat here. The Bianca has more flexibility than a lever for shots with higher water volumes. It has no advantage in being able to do fast shots with short preinfusions, since the Biaanca's E61 group head takes about 7 seconds minimum to ramp to full pressure.

*I used the Bunn with the Turkish burr set, which I found very tasty compared to a manual Turkish grinder, or the ultra fine grind from the K10. But I have no side by side experience with the EK43,