Back when I had my Vetrano 2B I had a repeatable process honed that would provide better results on lighter roasts. No line pressure, just running from the water reservoir.

I run the hot water into a cup to preheat, which in turn would start the pump to refill the boiler. After the pump stopped there was always around 2 bar of pressure showing on the brew gauge. Load up and insert your portafilter, lift the lever enough to let the pressure release onto the puck, then fully engage the lever.

Here is a video of my process (I don't show the hot water draw prior to the shot in video though)

If you turn the volume up you can hear the puck wetting/preinfusion. I also cut the pump off and taper the end of the shot.
I've since moved away from e61 machines as they leave a lot to be desired, and now own a Lelit Elizabeth. Someday I'll buy a speedster....someday

Qrumcof wrote:Thanks, I'll try it..

But I noticed when I would start the pump for <1/2 second (trying to PI), that all my coffees were tasting good, but tasting the same.. Have you experienced this at 7.5 bars? I've also tried engaging in the pump full pressure until I see the first sign of espresso at the bottom of the basket (then wait 25s). Although I didn't take note of the bars at the puck when I did the quick pump on/off cycle (it probably never rose at all).


FYI, I do have flow control, very similar to the picture above.. I don't have a way I know of to set ml/sec, but I see the pressure in bars change with the flow control. I have a manual flow control set by turning a knob, and a lever that turns on the pump.

So if I understand correctly, the pressure should rise because of the pucks resistance to flow?

See this video for flow control mapping and calibration:
The part you're interested in starts around 2:25

shotwell wrote:This is probably a needlessly long post, but the word preinfusion confuses a lot of people. It's a misnomer.

....

Infusion is the soaking of flavoring ingredients to extract.
Percolation is passing a liquid through a porous substance, in coffee it is meant to extract solubles as the solvent (water) passes through.
Espresso is primarily a percolation method, not infusion.

Since espresso isn't really an infusion method, the term preinfusion is a bit silly. The only infusion that happens is during what is traditionally called preinfusion! What you have are actually a few distinct steps.
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Your points are well taken, but I would say that "pre-infusion" is not really a misnomer, since it describes the early phase of espresso making just before the puck gets fully saturated with water and then begins to pass from the portafilter to the cup. During that phase (whose time can be controlled by spring tension in the e61 "preinfusion chamber" or by means of a "flow control device," the puck is being infused. Since this occurs prior to the extraction that forces the cofffee under pressure to pass through the portafilter (what you call percolation and most folks here would call extraction), it seems quite reasonable to call this early phase "pre-infusion."

JRising wrote:Go ahead and set the flow-control to closed and raise the lever... You'll probably get a drop through the showerfilter every 2 or 3 seconds. Turn the flow control just the slightest more open so that you're gettng 4 or 5 drops per second (or maybe the thinnest trickle that breaks and reforms) and remember that position.
In that position, you won't have to raise and lower the lever, that will be good for your pre-infusion. Put your portafilter in with the prep, and raise the control lever, the trickle will "pre-infuse" your prep for about 8 seconds (if your idea of a thin trickle is the same as mine) and then the group gauge will begin to rise. At that point, open the flow control to let pressure rise to 8.5 (or something) across the puck, when the shot is about 2/3 done, start closing the valve slowly to decrease the pressure drop across the puck (and maybe stop the channeling, then lower the lever to stop the brew.

This seemed to work well.. But I need to try it a few more times.. I think I had the drips too fast.. And I got confused and forgot to reset the lunar scale for the extraction.. I pulled 20g shot, and it looked good (thicker and darker than my previous shots).. no idea on the time tho.

This is a very simplistic approach that is FAR from ideal for extracting medium light to light roasts. You really should properly map the flow rate for various positions on your valve and try the profile I posted.

shotwell wrote:Calling the percolation phase the extraction phase isn't sufficient; extraction happens while the puck is soaking before water flows. That extraction can't be used before flow comes through the puck, but torturing the language when we have adequate alternatives is just confusing the issue. Percolation is a description of a specific extraction method....
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Using the term preinfusion to describe infusion is a misnomer, regardless of historic or colloquial use.

I was just quoting what you wrote earlier:

Infusion is the soaking of flavoring ingredients to extract.
Percolation is passing a liquid through a porous substance, in coffee it is meant to extract solubles as the solvent (water) passes through.
Espresso is primarily a percolation method, not infusion.

Therefore by your own definition what happens while the puck is soaked but before coffee begins to exit the portafilter we are dealing with an infusion phase, which since it comes before the flow of solvent (water) carries the extracted solutes to make the espresso in your cup, it seems tome quite erasonable to refer to that early phase as a preliminary, or pre-infusion phase (i.e. prior to the time espresso leave the portafilter). Yes, calling it just "infusion" would be OK, but that could be confusing as well, since it conflates two very different extraction methods...infusion extraction and espresso extraction, which as you must know are completely different methods of making coffee. Valente's original e61 patent describes in detail how the group allows the preliminary infusion to occur and vary its duration.

You of course are free to call it whatever you want. It's been called Pre-infusion for more than 50 years (since the invention of the e61) and I suspect that most of the folks who use the term with regard to espresso making are not at all confused by what it means.

I agree that it's been called "preinfusion" for decades. Long before pressure/flow profiling was a thing.

Now that profiling is a thing for more than a small handful on the fringe, being clear about the various phases from "pump on" or "valve open" to "yum" has broader value. I believe it helps people understand the processes better and, hopefully, allows them to make better decisions about how to control their machines and get better espresso as a result.

Pressino wrote:You of course are free to call it whatever you want. It's been called Pre-infusion for more than 50 years (since the invention of the e61) and I suspect that most of the folks who use the term with regard to espresso making are not at all confused by what it means.

Disregarding the paraphrasing and misquoting that you refer to as quoting, the whole point of my post was that it is past time to move on from a term that confuses new users.

To illustrate the point; is partially lifting the lever and allowing some water to come onto the puck preinfusion? If no, why not? It meets the definition. This confused at least one person in this thread at one point.

I was not aware that this has been called preinfusion for 50 years, but I'm not about to go dig for the original e61 patent or learn enough Italian to properly translate it and either prove or disprove that.

We can agree to disagree, and I'm happy to do that. I'm not at all confused by what 'preinfusion' means as it is used currently, so have no issue with people choosing to keep using the term. I interact with a huge volume of users new to profiling and advanced preinfusion techniques, so I'm a little more sensitive to how people interpret this than you would expect.

PIXIllate wrote:This is a very simplistic approach that is FAR from ideal for extracting medium light to light roasts. You really should properly map the flow rate for various positions on your valve and try the profile I posted.

I intend to try it, but I need to wrap my head around flow rate, versus bars pressure at the group. In the past Ive always monitored the pressure at the group when trying to use flow control.. But found it nearly impossible to get the bars where I want them while the shot is pulling (because it happens too fast).

I'm hoping "mapping" grams/sec will give me a way to use flow control and have consistency..

Also, my flow knob turns 2 1/4 turns (damn).. Wondering if that's normal..