I just received a Richard Penney bottomless portafilter (49mm stainless steel) to be used with my Olympia Cremina Millennium Edition machine. I decided to shoot a video to post here to get some feedback/critique suggestions.

I bought my Cremina in 2004, and have used it regularly since, but I just bought this new bottomless portafilter, and have pulled perhaps 10 shots with it total so far.

I shot the video of the 4th shot I pulled yesterday morning. The first two were a bit on the sour side, and I think those shots were under extracted (quick pulls) so I adjusted the grind and the third one was a bit less sour, and the final shot (the one shown in the video) tasted wonderful. It was sweet without any hint of sourness or burnt flavors.

The video has the specs, but here they are again anyway:

Equipment/Specs:

Olympia Cremina Millennium
Richard Penney bottomless portafilter (49mm stainless steel)
Intelligentsia Black Cat Espresso
Mini Mazzer burr grinder
Shot Time = 26 seconds (from start of preinfusion)

Three things I forgot to add to the specs listed in the video clip:

1. I also bought a Elektra A Leva MCAL Espresso Machine Double Portafilter Basket to be used with my new Penney bottomless portafilter. It's a bit deeper than the stock double basket that came with my Cremina.

2. The shot pulled in the video clip had approximately 15g - 16g of coffee in the basket.

3. Tamp pressure was very light (approximately 4 lbs) with a bit of a polish.

It looks like a great shot, but I'd be the first to admit I have no experience with the bottomless portafilter.

What exactly are you looking for with it?

I found it neat to see the crema mixing and draining into the glass and I would guess you can get some ideas about how consistent the pressure is through the stroke?

Well, you know although I've been making espresso nearly daily with this machine for about 6 years now, I still feel like a beginner. I am a complete beginner when it comes to using the bottomless portafilter. I have read some tutorials, and seen a bunch of videos, but the nuances are perhaps lost on me until I have more experience pulling shots with the BPF.

Through research here and on another coffee forum, and trial and error, I have found over the years what tends to work well for me.

I don't switch espresso roasts very often, having settled in on Black Cat Espresso from Intelligentsia, mainly because I find it pleasing and also they have conveniently opened several locations in Los Angeles, including one in Pasadena, where I live. Back in 2004, before they opened their first LA shop, I was taken to their flagship shop in Chicago by a good friend I was visiting. He's a coffee and espresso nut too, and I was impressed with the espresso the Barista pulled for me that day, and I left with 2 lbs. of Black Cat to take back home with me. For a while I was ordering and having it shipped to me on a semi regular basis. Now it's just a short drive to pick it up locally. Of course the price has gone up over the years, so it seems like I'm paying as much for it locally now as I did when I had it shipped!

Anyway, back when I first got this machine, I was playing around with 30 - 40 lb. tamps, and finding it tricky to dial in the right grind so as not to choke the machine and to extract the best shot I could. With a lot of experimentation, and a gnawing feeling that I shouldn't have to work the lever so hard in order to get a good, sweet shot of espresso from the machine, I started playing around with considerably lighter tamping, and have settled in on around 4 lbs. or so with an appropriate grind allowing for about a 25 sec pull. Well, for me it was a revelation. I was able to get consistently great shots from the Cremina, with far fewer sink shots, and a lot less pressure on the lever. I still have to exert force, but now it seems like a reasonable and safe amount of effort compared with some of my early experience going by the book.

Well, if you're still with me, I still play around with the variables and am still chasing the so called God shot, and hope that the BPF will help me to further refine (or revolutionize) my technique.

I made this first video, and will continue to make some new ones from time to time to see if I can glean some insight into what I could be doing better.

Some of the things I have learned from reading up on the subject and viewing other BPM video clips is that good things are: even initial dispersion of water through the puck and portafilter evidenced by uniform trickling of water through the basket bottom screen, that becomes a conical centered single funnel after say 8 - 12 seconds. Also, tiger striping of the stream is a good thing. Not seeing premature blonding of the shot is also sought after.

Bad things are: multiple streams, and or a conical stream that is not centered, spraying, early or complete blonding, lack of tiger striping, etc. These can be indicative of channeling due to poor distribution of grinds in the portafilter and/or poor tamping technique. There are all kinds of things that can be diagnosed by viewing a shot pulled with a BPM, but since I am new to using a Bottomless Portafilter, I am still trying to learn the nuances of what I am looking for.

Here's a guide from this site that explains a lot of what one would want to look for:
http://www.home-barista.com/naked-extraction.html

As I mentioned in my first post, I was hoping some more experienced Baristas here with both BPMs and perhaps even owners of Olympia Creminas might be able to give me a critique and some suggestions to try.

From what I can see, compared to other videos I've seen, the tiger striping can be more pronounced and perhaps have tighter striations between the lighter and darker parts of the streams. Also, I wonder if the beginning of my extraction showed less than ideal evenness of first drops through the bottom screen of my PF basket. Does the timing of the various parts of the pull seem right to others with more BPM experience?

I started the count of my shot extraction from the beginning of my preinfusion, which I would say is at 00:11 into the video clip.

Anyway, if anyone cares to give an opinion or a suggestion for improvement, I'm all ears.

Mahalo

Nom de Guerre wrote: I still have to exert force, but now it seems like a reasonable and safe amount of effort compared with some of my early experience going by the book.


Mahalo

This post was all about going by "the book" - unfortunately, the book here refers to pump machines. You should have seen how much hate mail I got once I called this method out. LOL! Especially with the "no headroom" comments I made.

If I had to make a guess, I would say you might need either just a slightly harder tamp and/or slightly finer grind. In your video, near the end, do you see how the width of the extraction widens out? That's usually due to the grind being off and/or the tamp being too light. The grinds are allowing the water to flow too rapidly and as the velocity of the extraction increases, the flow starts to expand.

What you really want is for the extraction to form at the base of the portafilter, then pool in the center and drop off. The coffee should hug the portafilter screen a bit more and then you will tend to have more of a straight line down from the middle, as opposed to a "V" shape that is falling off the base of the portafilter basket/screen.

You can still get a very tasty shot with a wide flow like you are getting, but if you can slow it down a bit and keep it more under control, it might give you better crema and more body to the shots. Like I say, what you want is a slow extraction coming out of the bottom of the screen, which pools into the center and drops off in a thin stream. You don't really want a rush of water that is beating a path out of the filter (which results in that wide funnel looking flow as seen in your video).

Like you, I use a very light tamp. Maybe 5 lbs or so. However, if the flow is doing the funnel thing, then maybe step it up to about 5 or 15 lbs. Also try taking your grind a bit finer (maybe 1 or 2 clicks, depending on what grinder you have). In my experience, you want the tamp hard enough to keep the compacted grounds together, but not so hard that you promote channeling. Then from there, adjust the grind in order to slow down the extraction path.

If you are using a lever machine (vs. a pump driven one), then start out the pull very slowly, so that you don't induce a channel. If you come in too hot, you will tend to punch a hole into the top of the puck and one you do that, it will cause everything to dig through that spot. Using the naked portafilter, watch and you will want to see the extraction build up in a circle around the screen fairly evenly. When I start my pull, I usually go fairly slow in order to avoid channeling in one area.

Ray

Ray,

I really appreciate the critique and suggestions. That's exactly the kind of feedback I was hoping to get in response to posting the clip. I will try out your suggestions tomorrow and see what improvements I can manage.

I'll post the results here.

Thanks again!
Anthony

You are most welcome Anthony. I've been getting some really great shots from my older La Pavoni lately. I'll see if I can make an updated video for ya. Below is an older video, but you can sort of see what I'm talking about as far as the shape of the extraction under the portafilter (I pull the shot @ about 10:45 in the video below):



Anyway, since recording the video above, I have tightened up my grind a bit more, which has resulted in a slightly slower/better extraction. I would guesstimate that I'm using about 15 to 20 lbs on the tamp. I've also been pulling the shots a bit longer (about 1.5 ounces maybe). When everything is setup properly, I'm seeing some very good shots and roughly 25 to 30 seconds on the pull.

BTW, don't be scared to lift the handle and get some additional water into the group head mid-shot. On my machine, in order to avoid over heating, I flip the power on/off quite a bit (on the "I" setting). This sometimes catches me with not enough pressure in the boiler to push as much water as I need into the group head (and this manifests itself as the lever going down about half way before you feel any pressure). In those cases, sometimes I quickly flip the machine up to "II" and then lift the handle back up to allow a bit more water to come into the group head (typically after I've started some of the shot flowing). This allows me to finish off with a decent volume shot, but without having to have the machine super hot from the get go.

Here's a shot of tonight's espresso, using the above method. As you can see, plenty of very good quality crema and also a very smooth/rich flavor (even with butchering up the pull into two strokes)



Ray

Hi Ray, cool video but you really should get yourself a scale, as it will make repeatability more reliable. I bought a cheap little guy from Lee Valley. Think it was $20. You can find cheap ones at your local smoke/headshop. Best one out there though is the Tanita 1479. Not cheap though.

I usually don't weigh the coffee. I just go by volume on the grinder and/or portafilter basket and eye-ball it . I do have a little gram scale here for measuring weights, etc. but usually don't use it when it comes to pulling shots.

In the video above (@ about 6:00) I do weigh the coffee, however. I think it was about 12.5 grams in this particular case.

Ray

RayJohns wrote:
In the video above (@ about 6:00) I do weigh the coffee, however.

Clearly I see it now. Don't know how I missed it.