Are we supposed to have a mud layer? On my v60's all the coarse grinds i find are typically at the top, unlike yours?

Very interesting study, saved me some money too because I had been considering the Kruve lol

Is it really gel? Or do the wet fines just appear gel-like under magnification?

wanderlustjohn wrote:Are we supposed to have a mud layer? On my v60's all the coarse grinds i find are typically at the top, unlike yours?

Smaller particles should naturally find their way to the top of the coffee due to mass (if these don't cling to larger particles). But the quantity depends on your brewing technique; agitation, movement/flow of the water and coffee grind.

It also depends on the bean/roast and grinder for some reason.

A small site note: in northern europe we tend to use very light roast, this requires a very fine grind, this seem to contribute to a thicker and more pronounced mud layer

I think the wet grinds need to be dried, to get a propper picture of the particles

malling wrote:Smaller particles should naturally find their way to the top of the coffee due to mass (if these don't cling to larger particles). But the quantity depends on your brewing technique; agitation, movement/flow of the water and coffee grind.

With a low agitation pour, I don't seem to get a mud layer, much like Nick Cho here http://www.youtube.com/watch?v=mupueSMHBJQ
I would expect with a low agitation pour, that fines are washed down with the flow of water (as is hypothesised for the extraction mechanism). With high agitation or perhaps a "dump" of water, there may indeed be a mud layer as seen in Matt Perger's vid here: http://www.youtube.com/watch?v=MPDfn--vxK8

aecletec wrote:With a low agitation pour, I don't seem to get a mud layer, much like Nick Cho http://www.youtube.com/watch?v=mupueSMHBJQ
I would expect with a low agitation pour, that fines are washed down with the flow of water (as is hypothesised for the extraction mechanism). With high agitation or perhaps a "dump" of water, there may indeed be a mud layer as seen in Matt Perger's vid here: http://www.youtube.com/watch?v=MPDfn--vxK8

If you watch closely you can see Perger is using a finer grind and a much lower coffee/water ratio, giving a much shallower coffee dept, where's Nick Cho is using a rather coarse grind and a massive dose. This is also going to have some sort of an effect. But yes pouring agitation does have some effect on it, as I also mentioned.

Nick Cho is using 72,5g/l, Perger is using a more traditional 60g/l.

Now Nick Cho's video doesn't tell us anything about extraction, Pergers on the other hand dos. Nor does it tell us what grinder he is using. I have had two grinders next to each other (EK and Vario with steel burrs) the latter did not have a mud layer with the same brewing technique, water to coffee ratio.

I'm not trying to disagree - I'm commenting on the points you've raised... And supporting them.

On the other hand, if your opinion is that you always get a mud layer... But only within certain parameters, then that's not "always".
Nick is likely using a Baratza conical.

Just did a Nick inspired brew with a coarser grind, more slower gentle pours as expected the mud layer looked like it where less pronounched but did not vanish (not coarse enough), obviously I need to practise to pour a way that suits a coarser grind ... as I use another technique to suit my very fine grind.

But very nice brew with a crisp acidity

wanderlustjohn wrote:Are we supposed to have a mud layer? On my v60's all the coarse grinds i find are typically at the top, unlike yours?

I first encountered this "mud layer" with large bulk grinders - like Ditting and EK43. Like Malling also reports with EK43 versus Vario Home.

I pulse-poor with out restrictor. So it's not due to low-agitation pooring technic (not only ? maybe more things influence).

The mud layer must be the "separated fines" ... the fines only connected to other fines - and not the larger particles.

I have started stirring my dry grind before placing it in the filter - with the intention to get the separated fines to stick to the larger particles. This morning I just noticed my after-brewing grind on the V60 did not have the mud layer - or at least less mud layer. And a very nice taste too.

But surely more experience is needed. Would like to hear what others experience.

PS: More details about agitation in my brewing - I stirre with a spoon in the beginning of the bloom phase. When all the water is added (I try to do that within 2 minutes) then I shake and spin the V60 to get an even grind bed and avoid channeling.

AssafL wrote:I wonder if the Gel is leftover polysaccharide hydrocolloids.

Same polysaccharides probably give Espresso the thick unctuous body.

Thank you for sharing. Very exciting thread.

Sounds very plausible !