Hello all,

I've been trying to dial in a coffee using 2 methods but the results are wayyyy different

Coffee: Arabica 100% https://cuendet-malongo.ch/cafes-en-gra ... elaar.html

Method 1: Picopresso + 1zpresso JMAX

Trial and error for the grind size (141 clicks) to follow the recommended number of pushes with the Picopresso. 19g in 39-40g out in 40-45 seconds with 10s of pre-infusion after the first 10-12 pushes. Remaining of the shot using regular pushes to keep a constant flow rate.

Result: Coffee tastes super smooth, velvety and with some coconut? flavors. Tried the same recipe 3 times and I can achieve the same result

Method 2: Lelit Bianca + Niche Zero + VST 15g basket

Trial and error about the grind size (as low as number 7 on the niche!).15g in 30g out in about 27-28 seconds @ 94degC without preinfusion / low flow / profiling. Pressure set to 9 bars.

No sign of channeling during the extraction, which looks really nice and smooth. The cup ends with a nice crema, but tastes really bitter. The result from Method 1 is amazing and so far, I can't reproduce it with the Bianca.

I've tried to increase the grind size on the niche, but the shot runs way too fast. tried lowering the temperature to 91degC but no significant changes...

Any pointers I should look at?

Thank you in advance!

From what I can tell, that is a dark roast coffee of unknown origin and processing, priced at 25€ a kg.

I would put the VST basket away with either dark roast or commodity grade coffees. It is likely causing you more trouble with puck integrity and grind and may be revealing flavors in the coffee that you don't like. Stick with the basket that came with the Bianca, or something that is not a high-flow basket. Some of the IMS baskets with tapered or curved walls and reduced hole coverage would be another option if you don't have the stock basket.

My guess is that the Picopress is extracting at a significantly lower temperature than the Bianca. That lower temperature can sometimes mitigate the inherent bitterness in dark-roast coffees. Stopping the shot "early", before the stream lightens, is another trick for working with dark-roast coffees.

I'd also consider dropping your blind-basket pressure. You might make a big step, such as down to 7 bars, to see what that does. Then you could try 8 (or 6) and see if you like the results better. Changing brew pressure will require changing grind (or dose).

hi Jeff,

Thanks for the suggestion.

To avoid changing too many parameters at the same time, I only changed the temperature and dropped it to 88degC.
It is indeed now leaning towards the same Picopresso's taste. There is still some differences, but the extreme bitterness is now almost gone.
As you mentioned, the picopresso brewing temperature is much lower than the 94 degC set on the Bianca and is impacting the overall shots tremendously.
Will keep that temperature constant and adjust other parameters such as extraction time and pressure and see where it is going.

Overall, based on a little experiments I've done, it seems the picopresso is more forgiving with mainstream dark roast coffee than the Bianca. I suppose I'll lean towards specialty coffees (which I've already tried and taste amazing) on the Bianca/Niche/VST combo.

my workflow on picopresso does not work like this!!!

time is out and it's either hard pump or easy pump! When it's hard pump I reduce the input dosage a little...
the darker the roast the easiest the pump should be...

output grams are important but not a deal breaker for a nice cup!

lots of preheating with lighter roasts.

with bianca I would try extremes just out of curiosity but dark roasts are lower temps and lots of flow

my 2 cents!

Since dropping the temperature got you on the right track, you could try going even lower. I go as low as 188F, so around 86.5C, on darker roasts on my Bianca. It really does help to tame the bitterness and bring out a smoother drink IMO.

hello
just to continue on the subject, i finally am able to reproduce the shot made with the picopresso on my bianca/niche setup.

overall the suggestions given were correct.
i reduced the brew temp to 86degC and had to play with pressure profiling to match the picopresso extraction :
- middle open paddle for the first 5-6s to reach 2 bars
- close the paddle entirely for 10s .. first drops appear just like the picopresso. volume is about the same
- after 10s, ramp up the pressure slowly to reach about 6-7 bars
Total extraction time: 40-45s

it's amazing to see how pressure, temperature, pre infusion impact the shot .. that goes from horrible bitter coffee to really nice shot..

thank you all for the replies

^^^glad to hear it's all working out. The Bianca is at the top of my new espresso machine list.