Capuchin Monk wrote:He was saying, "There's always channel in your espresso no matter what...". His point was, the pattern such as coalesce to the center ("rat tail") will hide it from the view more than "raining" pattern.

Yeah, I mean I'm no physicist, but it seems to me that even with perfect distribution through the puck, the result out the bottom could look like evenly dispersed rain, radially symmetrical multiple streams, or a single stream. How the drips coming out of the basket join together (or not) seems like it would be more about the viscosity of the fluid, how hydrophilic the basket surface is, the crema being produced, etc. It leads to people being annoyed they can see the basket, even if the shot is great. However, the opposite could be true as well - you could have an asymmetric extraction but the fluid is so foamy it covers the bald spot you'd otherwise see under the basket, hiding behind a nice thick cone of crema.

Personally I've observed, for example, donut extractions where there is obviously zero flow through the center but the curtain of foam coalesces over it and hides it from view pretty quickly.

espressoren wrote:Personally I've observed, for example, donut extractions where there is obviously zero flow through the center but the curtain of foam coalesces over it and hides it from view pretty quickly.

Logically, the raining pattern would be an indication of less channeling than anything else since the dispersion screen above the portafilter shoots water in rain pattern, very evenly distributed rain. Even for the bowed baskets, it would initially show raining pattern before it eventually coalesce to center, as shown with my VST basket.

Pardon the intrusion...very interesting discussion..far above my paygrade, I'm afraid.
I do a question:would having a puck screen on top obfuscate the supposed benefits of these new basket designs? Same with paper on the bottom. If this has already been asked, apologies.

One of the working theories about these baskets is that they can help in more evenly extracting the coffee. A puck screen on top should end up either doing little advantageous about evenly starting the flow, or perhaps help a bit. Filter paper on the bottom is thought to help even out the flow out the bottom. I haven't heard anyone claim that they are counter to the third-generation baskets' extraction performance.

Some people who have been using filter paper on the bottom are hoping that these newer baskets can eliminate that step. My impression is that there isn't a solid opinion on that yet. Too many things changing still for me to have confidence even that my observations over a half-dozen coffees are extensible across even a narrow range of coffees, burr sets, and extraction approaches.

Thanks, Jeff.

I use puck paper and a shower screen with the pesado basket. With my VST basket, the puck paper definitely speeds up the flow, I grind about 2 notches finer on the Niche Zero/Duo when I use it. With the Pesado, I'm not really sure if it further speeds up flow (as there is already very little resistance), but I prefer to use the paper and screen for cleanup reasons - it eliminates soupy and stuck pucks, makes it easier to knock out the puck, and also the shower screen fills in some headspace so I can use smaller doses. Filtering out some of the oils in espresso could (maybe?) help with cholesterol, who really knows.

gobucks wrote:it eliminates soupy and stuck pucks, makes it easier to knock out the puck, and also the shower screen fills in some headspace so I can use smaller doses. Filtering out some of the oils in espresso could (maybe?) help with cholesterol, who really knows.

Paper does filter out the oil. That oil has flavor. In other words, the paper filter reduces the coffee flavor. As for the soupy puck, it may have more to do with the machine's group head design (pressure release solenoid) than filter because I don't get soupy puck as shown here and I don't use any top screen or bottom filter, .

Crema I can easily taste test and don't find adding pleasant flavors. At least one person finds extracted coffee oil to have an unpleasant flavor.

Jeff wrote:Crema I can easily taste test and don't find adding pleasant flavors. At least one person finds extracted coffee oil to have an unpleasant flavor.

Déjà vu: WAFO baskets

Separating out one component and tasting it is an interesting exercise. There are components of many foods that, by themselves, don't taste good. Would it be better if those components could be removed? Would you prefer an orange or strawberry without any of the bitterness of the membranes? Or what about barbecue without the harshness of the charred exterior?