The issue I have is it remains quite sour as I keep grinding finer and finer until suddenly the sourness is more balanced but it's also too astringent/bitter. I have to brew with much hotter than normal temperatures or approach 1:3 to remove the sourness but with those variables, I'm also getting a drying/bitter aftertaste.

Are you suggesting tweak the default profile to decline temperature by even more than 2ºC and lower pressure even further? It typically starts at 8.5 and ends about 7.5 for me.

malling wrote:As already suggested several times grind as fine until astringency hit, decreasing temperature profile, lower pressure around 5-6 bars and slower flowrate at later stages.

It's not easy but it's doable.

To be honest I didn't get anything likeable even from the Commandante from very light roasts (DAK,MOK filter roasts). I don't like the espressi from the good espresso shops since they lack balance in my point of few and are too sour. I use SSP HU 98mm burrs in a Nautilus and profile used by some germans. Which is like a short 7 seconds pre infusion phase, 5 sec bloom and then a peak of 5-7 bar until 10g coffee hit the cup and then declining to 2 bar until 1:2 ratio is hit. Extracted at declining temperature starting at 88°C ending between 75 to 80°C and for 40-50 s. The niche I think is not really suiting for light roasts. I wish you good luck, but the really light stuff prefers 64mm MP or 98mm burrs from my experience.

FineGrinder wrote:The issue I have is it remains quite sour as I keep grinding finer and finer until suddenly the sourness is more balanced but it's also too astringent/bitter. I have to brew with much hotter than normal temperatures or approach 1:3 to remove the sourness but with those variables, I'm also getting a drying/bitter aftertaste.

Are you suggesting tweak the default profile to decline temperature by even more than 2ºC and lower pressure even further? It typically starts at 8.5 and ends about 7.5 for me.

You need to lower pressure so it doesn't exceed 6 bar at peak pressure.

Run lower flowrate at end.

I sometimes done a pre infusion 10-20sec on some, this can sometimes allow 1:2-1:2.5 ratio pulls, you can also introduce a blooming after preinfusion, then just let the preinfusion go no longer then 7-10sec followed by a 5-10sec bloom. In total don't let it exceed 15-20sec.

As I wrote it's not easy and it depends on the coffee.

Experiment with the temperature drop, starting temperature can be lower then what you do.

But in the end you probably want to get a grinder that take Cast or Unimodal burrs as these dos not exhibit those issues. Currently that is 64, 80, 83 and 98mm grinders.

Curious what your rationale is behind these parameters. I understand the extended contact time with longer pre-infusion but why do you opt for lower temperatures and pressures?

I think I've concluded Niche is just suboptimal for lighter roasts and I will definitely need to change grinders. I've pledged for Timemore 078s but I'm wondering if it's going to be as unimodal as the high clarity flats.

GorchT wrote:To be honest I didn't get anything likeable even from the Commandante from very light roasts (DAK,MOK filter roasts). I don't like the espressi from the good espresso shops since they lack balance in my point of few and are too sour. I use SSP HU 98mm burrs in a Nautilus and profile used by some germans. Which is like a short 7 seconds pre infusion phase, 5 sec bloom and then a peak of 5-7 bar until 10g coffee hit the cup and then declining to 2 bar until 1:2 ratio is hit. Extracted at declining temperature starting at 88°C ending between 75 to 80°C and for 40-50 s. The niche I think is not really suiting for light roasts. I wish you good luck, but the really light stuff prefers 64mm MP or 98mm burrs from my experience.

I'll give this a try. What's the rationale behind opting for a lower pressure? Is it because you need to grind coarser, which allows for a faster flow rate?

Yep, I've concluded I will need to upgrade from a Niche to a more unimodal style of flat burr. I've only had coffee from a 64mm SSP MP and it was definitely way more aligned to my preferences. The espressos were a little on the thin side but I'm guessing cast LS would give me a tick more body.

malling wrote:You need to lower pressure so it doesn't exceed 6 bar at peak pressure.

Run lower flowrate at end.

I sometimes done a pre infusion 10-20sec on some, this can sometimes allow 1:2-1:2.5 ratio pulls, you can also introduce a blooming after preinfusion, then just let the preinfusion go no longer then 7-10sec followed by a 5-10sec bloom. In total don't let it exceed 15-20sec.

As I wrote it's not easy and it depends on the coffee.

Experiment with the temperature drop, starting temperature can be lower then what you do.

But in the end you probably want to get a grinder that take Cast or Unimodal burrs as these dos not exhibit those issues. Currently that is 64, 80, 83 and 98mm grinders.

FineGrinder wrote:Curious what your rationale is behind these parameters. I understand the extended contact time with longer pre-infusion but why do you opt for lower temperatures and pressures?

I think I've concluded Niche is just suboptimal for lighter roasts and I will definitely need to change grinders. I've pledged for Timemore 078s but I'm wondering if it's going to be as unimodal as the high clarity flats.

With these Burrs you extract quick and fast.Therefore if you don't want to always want to hit the perfect grind size to get a good tasting shot you need to lower the extraction a bit. The shots won't give you a lot of crema or better said close to nothing. It's more or less a way to give you a small window in which the coffee taste good and is balanced taming acidity and not being bitter.
And to be fully honest there were some discussions in the german forum one guy came up with this profile but with a 2ml/s preinfusion. I tasted it and had the idea a faster PI might help. We settled with 5ml/s. The other guy made a ton of tests. The lighter the coffee the more work you need to put into it and him and I hate basically roast flavors and only buy the (ultra) light filter roasts.
For comparison I tried the other profiles which are talked about a lot, but they are normally too bitter for my taste and not balanced enough. The hype around Turbos I don't understand, there I never got something really balanced. Turbos for me are never bad but also never great. I think they are really good for coffee shops, but not if you want to drink the "god" shot.
I can not say anything on the Timemore my feeling from reviews is it is more towards the 83mm burrs, but maybe its even better than 98mm I hope I get to test it some day.

That has generally been the case for me as well with the Niche. Even when a roaster has given a specific espresso recipe recommendation (usually fairly traditional parameters), I have often had better results (sweeter/more balanced) doing something 1:3 in ~20s at a lower pressure.

I'd drop pump pressure first. It's cheap and relatively easy.

If that doesn't get you where you want to go, I'd try different burrs. The Lagom Mini and Cast v2 burrs both do a good job, in my opinion. They are both a bit less revealing than the 64 MPs. I generally prefer the Lagom Mini for espresso as it tends to be a tiny bit more defined in flavor separation. Tiny bit. For my tastes (Tim Wendelboe "filter" and lighter) I wouldn't reach for any of the traditional burrs, Mazzer, ItalMill or similar.

The DF64 has revealed its design and implementation flaws. If you get a good one and don't expect it to be aligned at filter grind sizes, they are functional. I don't know if the DF83 has resolved those issues or if it has others.