I've heard that looking at the coffee puck after making an espresso can tell you a lot about the technique and how the extraction went. This morning I was taking the bowl that I put the coffee pucks from making espresso out to the compost pile, and for some reason decided to take a look at one of them. That's when I realized that although the pucks looked pretty good to me, I had no idea as to what I should be looking for. Here's a picture of one. I lightened the picture to bring out the detail. The actual puck is darker brown than what's seen here. [upl-image-preview url=https://i.imgur.com/Ak3gxpa.jpeg] What I can see is that there aren't any holes, and that the surface is pretty uniform in terms of color and texture. It looks like the edge of the puck is darker in the lower left quadrant, but that's bad lighting. Is this the goal? Am I missing anything? Thanks!

@"wilburpan"#p28079 I tend to not just look at the coffee puck but also how easily it comes out of the portafilter and how clean or otherwise the portafilter looks after the puck is removed. Does the portafilter look like a watery mess? Are there oily signs on the base? All of these I find can give an indicator whether too much space was between the coffee and shower screen or too fine a grind etc. In conjunction with the flow of the extraction, they can help to give an idea of where to tweak to get the perfect cup

@"coffeealex"#p28085 Thanks for the info. For the most part, I don't have any real problems with getting the puck out of the portafilter, and it comes out cleanly. If there are differences between pucks in terms of how easily I can get them out, it's more that sometimes I let my 9Barista cool down before taking it apart to dispose of the puck and clean it, so the puck is relatively dry. And sometimes I'll do that right away, so the puck is more wet. But otherwise, the pucks tend to look the same, like the photo above.

Puckology is almost useless. Whether not the puck knocks out easily and is watery isn't relevant the quality of the coffee you are producing. Some newer techniques involve leaving a spent puck in a bowl of water and if it falls apart it means it wasn't evenly distributed…or something along those lines. There's also an idea you can look at the bottom of the puck immediately after knocking it out and spot parts that have had more water through them to spot channeling. But the older ideas of chopping pucks in half and looking for pinholes etc has been discredited much like other older ideas like splitting shots and stopping when shots start 'blonding'.

@"wilburpan"#p28079 I see a tall dark stranger, and money in your future. It is almost certain that you will be colder this year, as the spirits gaze is upon you. Beware christmas and the mince pies. Avoid black cats and don't wear purple.

Coffee pucks — what am I looking at?

wilburpan

Rob1 DavecUK I’m getting the sense that this is one thing less I have to think about. I’m good with that. 😉

NewBoyUK

I saw above the mention of splitting shots. Is that snake oil in the sense that splitting a double spout shot is meant to be better than a standard one from a single?

Or is ‘old school’ claptrap thats been disproved over time?

tompoland

NewBoyUK if you mean using a spouted portafilter to divide the pour into two cups, then no.

Please let me know if I misunderstood your question.

Rob1

NewBoyUK No…as far as I know singles are supposed to be better than doubles when you actually manage to do then right because the lower dose is easier to extract. In practice it’s harder to produce a good single.

The shot splitting idea I was referring to was the ‘split the shot into thirds’ (or even more) and taste the output of each part to find the point you want to stop the subsequent shots.

tompoland

I made a post once (in my earlier and ever-so-slightly less ignorant days) expressing concern about my sloppy pucks. One wag responded simply with “it’s just as well we’re trying to make great espresso and not great pucks”. Funny and true. Rightly or wrongly, I stopped worrying about puck inspection after that.

John_Yossarian

This topic pops up every now and then. I know it is irrelevant to taste, but I personally (for practical reasons) prefer the pucks to be solid and to drop out easily from the portafilter. 😀 Otherwise I get “suggestions” from my better half.

I have, on several occasions, broken the puck to look inside looking for dark and light spots hoping to understand the black magic that is behind a good espresso. I am still looking to no avail 😀

If you have time on your hands look further, but most importantly enjoy the coffee you make and do not bother what is left once the lever is pulled back. And as ### @DavecUK mentioned prepare yourself for some amazing things coming your way 😂

John_Yossarian

Rob1 I have stopped pulling single espresso many years ago after hitting the wall. The barrier for extraction is too low and the results have never been satisfactory. I can see a double spout being used for two single espressos, but the single basket is, IMHO, practically unusable.

wilburpan

One more question — if there was channelling, would that necessarily be seen in the puck? The reason I ask is that I use a 9Barista, and the design of the 9Barista is such that I don’t see the whole base of the portafilter as the extraction occurs, so if channelling is happening towards the circumference of the puck, I may not see it.

The espressos I get are uniformly good to excellent, so again, this might be in the category of things I don’t have to worry about. It does lead to another interesting question — if there’s channelling, and the espresso tastes great, did the channelling actually happen? 😉

DavecUK

wilburpan Channels can open and close, so probably not.

Doram

wilburpan One more question — if there was channelling, would that necessarily be seen in the puck?

If you have a really uneven extraction you might see that parts of the puck remained dry or had significantly more/less water going through them. If you would see that it would definitely tell you that something was wrong. However, if you don’t see it it doesn’t necessarily mean that nothing was wrong, if that makes sense. :)

Your puck looks perfect to me. If it’s looking the same from the sides and the coffee is good - I think you have a winner.

DavecUK

John_Yossarian Most singles are not good unless you use the large single with 10 or 11g of coffee in it. Many single baskets are not great.

See this article I wrote 15 years ago.

http://coffeetime.wikidot.com/filter-baskets

John_Yossarian

DavecUK I totally agree, with the large single the chances are one can pull a good shot. I meant the small versions as I have never possessed the large version.

MediumRoastSteam

You can always try a VST/LM Strada 7g basket. It also requires a 41mm diameter tamper.

Picture of mine here, back in the day:

prezes

MediumRoastSteam this is what I use in daily basis and getting great results with single shots.
I’ve been through a lot of single baskets before though including IMS the single which was acceptable but nothing comes close to this

CoyoteOldMan

41² / 58² = 50% so everything is good for a single vs. a double! (If your standard double is a 58 mm basket). With a 54… we’d need a 38 mm!