I recently installed La Spaziale’s “progressive pre-infusion” chamber on my 2 group New EK. Since installing the setup, I have not had any bad extractions to speak of. I have also been paying close attention to quantity of coffee in (18g) and quantity (weight) of liquid out (~18g). I typically like shorter shots, so anything 9-18g is usually something I enjoy more.
This was the first taste test to see if there is any appreciable difference between a shot with pre-infusion and one without.
Grinder: Baratza Vario
Machine: La Spaziale New EK
Basket: 18g Stock La Spaziale
Portafilter: Spouted double
Ethiopia Dry Process Yirga Cheffe – Aricha from Sweet Maria’s. The coffee is on its 6th day post roast, and to be honest, I took this coffee beyond what I would have liked. This is a “berry bomb” coffee at lighter roasts, however I probably took this into the first couple of snaps of 2nd crack before opening the door and hitting cool on the Behmor roaster. So, I would say we were probably at FC to FC+. It is a nice coffee at this level, but for a guy who loves fruity espresso, I blew it. The coffee exhibits mostly cocoa flavors with a little red fruit at the end.
While I was not expecting a dramatic difference with this “pre-infusion” setup, I did think there might be a slight improvement in the roundness to the shot. I was also curious if the extraction would go just as well on the non-infusion side.
Yirga Cheffe Espresso Shot 2
Both shots were 18g in and came out around 19g. Both smelled of dark chocolate with a hint of strawberry on the nose. First sips while they were fairly hot tasted identical. Slightly bitter dark cocoa, a hint of roastiness and a hint of red berries at the close.
I let both cool for a couple of minutes before taking my second (and final) sip. This is where it seemed that the pre-infused shot had a slightly more viscous mouth-feel and overall a more rounded flavor. The non-pre-infused shot seemed to be sharper.
What is This Worth?
Not a whole lot, really. Seems like a good reason to try it all again tomorrow morning with the Ethiopia Kaffa Chiri that is ready for duty.
- Pull more consistent shots.
- Test if there are any discernible differences with and without pre-infusion
- Most of the crappy extractions I get are probably more of a function of a lazy barista. However, I wonder if a “soft start” might be more forgiving.
- When I first bought this machine and before I plumbed it in, I drew water from a large bottle of water. Those first shots had the best body and balance I have seen on this machine (for the most part). I have constantly wondered if line pressure, pre-infusion, or some other mythical creature might help me recapture this legend.
The Back Story
I picked up a La Spaziale New EK for a song in 2014. It was less than a song, the purchase was so good it wasn’t optional. And, when you have a wife that is as amazing as mine, you get to have a commercial 2 group machine on your counter. The machine is unique in the way the heat exchange takes place and in the fact that it uses a 53mm portafilter. The smaller diameter portafilter has a taller basket than you would find on your run of the mill commercial 58mm portafilter.
After disassembling the machine last year (not that it needed it) to descale everything, I noticed that there is a port on the left side of the group heads with a brass allen headed plug in them. After poking around a bit, I found this pre-infusion kit for La Spaziale espresso machines at Chris Coffee. So, I tried to read up as much as I could over at Home Barista about the pre-infusion kit and pre-infusion in general. Suffice it to say that took me on a journey that made me forget all about the kit.
Fast forward to the present and a desire to refine my barista skills more. And with a good sum of money sitting in the paypal account, the order was placed for one pre-infusion kit. After all, what better machine is there to test any variance that might exist with and without the pre-infusion kit, then on a 2 group machine?
That’s all folks. Three pieces. The adapter on the bottom screws into the port after removing the factory installed plug. Then attach the tube to the adapter. Lastly attach the pre-infusion chamber to the tube.
Where the Magic Happens
If you look closely, you can see the spring that pushes against a disc at the other end. When there is sufficient back pressure (from a loaded portafilter) the spring will compress easing the initial water pressure the puck sees. A simple solution and I guess La Spaziale’s attempt to mimic the soft start of the E61 group.
The 2 Minute Install
The installation was a breeze. It took more time to remove the panels and coffee cups from the top of the machine than it did to install the three pieces. I removed the plug, installed the brass adapter and then the tube.
I bent the tube less than the S1 instructions noted as I didn’t need to due to abundant clearance.
Here is a view of the finished installation after the machine is put back together. This view is looking from below the front controls…where you would be if you were cleaning the floor. The chamber is barely visible.
Now, on to the good part…
UPDATE: 2 Weeks Later
The installation went off without a hitch…and without any leaks. From the start the chamber has worked as expected. I have been focusing on basic techniques of weighing in and weighing out recently and it has made massive improvements in shot-to-shot consistency…lazy in my old age I guess. With that said, I have not had a bad extraction (knock on wood) since I have installed this on the machine. The preinfusion takes about 5 seconds to bring the portafilter up to full pressure and it does seem to help make sure the integrity of the puck is not disturbed.
Next up, side-by-side testing with and without preinfusion.
Grinder: Rancillio Rocky (set to 2)
Espresso Machine: Rancillio Silvia w/ Auber PID
Temperature: Auber PID set to 218
Pressure: OPV set to 9 Bar
Dosing: 15 to 16g
Basket: Espresso Parts Ridgeless Double
Portafilter: Espresso Parts Naked
El Blanco Espresso by Johnson Brothers Coffee. From the Johnson Brothers Coffee website:
This lot is comprised entirely of the admired Pacamara variety of Arabica, a cross between the giant-beaned Maragogipe and Pacas, a selection of the heirloom Bourbon.
Blind Assessment from the Johnson Brothers website:
Gently bright and pungent in the small cup: fresh-cut cedar, buttery chocolate, night flowers, hints of apricot and pear. Impressively creamy mouthfeel; rich, flavor-saturated finish. Retains its buttery richness in two parts milk, with flavor dominated by a crisp dark chocolate.
Miss Silvia was warmed up for over an hour for each of the two sessions today and had two flushes somewhere around 20 and 30 minutes into warm-up.
It took me about 4 shots to get things dialed in unfortunately. Rocky needed to be tightened up a notch, which I did not expect. For these long beans, I needed to turn Rocky down to 2 from 3 (which seems to work well for many coffees). Once I managed to get the grind close, I worked on dosing.
Fortunately, the 17g dose I typically use was pretty close, but was a bit bitter. I have learned that lesson from Miss Silvia and decided to lower the dose. I went all of the way down to 15g, but found that something between 15.5g and 16g seems to work the best (depending on humidity).
Once I had El Blanco dialed-in, it became obvious very quickly that this was not going to be some dark fruit action. My wife and I were both surprised at how prominent the tropical fruit nose was. After sampling the fruit really came through on the mid-palate through to the finish….and a long finish it was. There was a nice chocolaty finish which was a little bitter for my liking, but that is more likely operator error than a “defect” in the roast or beans.
A very fine espresso indeed.
Tomorrow, I will play with the temperature a bit to see what effects that has and try to take a video or two of the extractions. It was really a nice espresso to watch as the crema production on extraction is impressive.
Disclaimer: I am not a Barista. For that matter I am not a good espresso maker. But, from time to time, I manage to extract most of the essence that the roaster intended from the coffee beans. These tasting notes are for my own diary of sorts and may be of interest to other Rancillio Silvia owners, espresso fanatics, or people who have too much time on their hands.