I have had very good success pouring tasty medium dark (Full City to Vienna) decaf shots, as straight shots and for milk drinks, due to a combination of Luca Frangela’s simple flow based profile profile, the EPHQ14 basket and my Niche Zero grinder. I get full bodied, full strength shots that taste good and have good length. Not a lot of flavour separation, but all else is good.
I tried using the same basket and grind and profile with a medium light (say slightly lighter than City roast) decaf bean, that tasted good at a local cafe but not on my Decent. The cafe labels this roast as medium, but I think that its just a tad lighter. The profile was set up to target 1.9 ml per second at 88C, with 15 in and 25 out (a 1.67 ratio). Increasing the grind from 5.0 to 9.0 on my NZ marginally improved the actual flow from 0.75 ml/sec to 1.0 ml/sec, but not the strength or flavour. Fyi, the pressure went fairly high to 14 or 15 BAR, which worked well with my tasty medium dark (Vienna) decaf bean from a local Italian roaster, but not with this medium light decaf bean from a more North American (specialty) roaster.
As I have been advised to pursue a faster flow (upto 5.0 ml/sec ) and longer ratio (up to 2.5) and somewhat lower pressure for nordic roasts, I set my target for this medium light (slightly lighter than City) roast at 3.0 ml/sec and the ratio at 15 in, 30 out (2.0). But as the EPHQ14 basket is a lower flow basket, I couldn’t get the flow up beyond 1.0 ml/sec, or the pressure down below 14 BAR, even at an 11 grind and a 2.5 ml/sec target. The taste remained weak and even somewhat sour(which I was able to combat by increasing the temp by 2C, to 90C).
Changing the basket to an E&B - IMS 14 increased the flow to 2.0 ml/sec, but the pressure remained stubbornly high
at 14 BAR! Taste is passable at best, with OK body, not enough strength, ok balance but not enough flavour or length.
Reducing the grind to 10.0 with target flows of 2.0 vs 3.0 ml/sec didn’t help, as the actual shots never flowed above 1.0 ml/sec, despite pressures peaking at 15 BAR. The shots had OK body but not enough strength or flavour and some sourness crept in.
Maybe this is the wrong profile for this type of bean?
Or maybe I need to grind ALOT coarser, say at 13 or 14 on my Niche,,which will hopefully get the flow up and the pressure down. But if I grind coarser will I not get sour taste notes?
I’ve never had much luck with beans that are lighter than Full City, and so welcome any advice, particularly around tweaking an advanced profile on the Decent.