Breville Dual Boiler- right tamper & dialing in

Beginner and pro baristas share tips and tricks.
vinodism
Supporter

#1: Post by vinodism »

Hello Everyone,
I recently got a BDB 920 and there is not for now. The blind max pressure is at 10 bars, and preinfusion set to 55, temperature 202 (the bean I am using seems light medium Colombian washed beans from Elm Roasters in Seattle),
https://elmcoffeeroasters.com/collectio ... an-caicedo
Flavors: LIMONCELLO, CARAMEL, ROSE.
I was dialing in with niche - 18 gms in and targeting 40, and I had to dial it quite fine than normally for other beans like Dolce by Vivace, so first shot around 12 on niche after recent calibration, at the given PI setting I see first drops around 15 second the pressure around that time for 5ish and it was a slow ramp up, I am using stock tamper and double basket. I got 40 gms in around 43-44 seconds and peak pressure after pre infusion was 9 bars.
The first shot lacked sweetness and I felt it was having some under extraction (I am quite novice but I felt the shots had sourness -may be fruity acidity can be perceived as sourness as the beans have listed limoncello in it but I was missing sweetness which was caramel and definitely no rose at all :D . So I thought may be there is some channeling because no distribution tool but I did some WDT with hair pin DIY and tamped gently doubting the tamper is not good enough so tamping hard may cause some channeling especially around the rim as it seems less snug.

So I moved the setting two notch finer( using the binary search kind of system) and this time again did same WDT and gentle tamp', this time I saw first few drops around 19 seconds and the ramp up flow was slower than previous. 40 gms around in 50 secnds and this time I thought to give analysis to the puck if it comes out clean, and I found that the puck actually stuck to the group and when i got it out it had serious dark color around the rim of the puck and there was lot less saturated coffee around middle lower portion. Definitely channeling !!

I have pulled decent shots on my expobar lever with e61 group head with the preinfusion that comes with e61 design, but never used pre-infusion as a variable before much may be just pre-wetting.

I would try again tomorrow from where I have started feels bad to waste such a nice coffee while dialing in :(

Here are my questions
What should be right temperature and PI value set based on light medium roast ?
Which tamper I should get for BDB which can stop the channeling from the circumference , I guess a leveling tamper would be better as that would remove some variability .
I was thinking to play with the stock BDB settings first before going to the needle valve mod.

Thanks for reading this long and somewhat unstructured post.


,

pcrussell50

#2: Post by pcrussell50 »

For your donut extractions, give this thread a read and see what you can glean from it: Help with donut extraction

For sourness, try higher temps, nothing wrong with 205degF, or longer pre infusion. Or both. Nothing wrong with pre infusing for 70 seconds if you can grind fine enough. And don't use a VST basket, if you are using one.

-Peter
LMWDP #553

vinodism
Supporter

#3: Post by vinodism » replying to pcrussell50 »

Thanks Peter for tips, I was preinfusing grinding fine enough to get pre infusion first drops at 20 seconds , the thing is after I am checking the puck It seems the circumference of the puck have very dark color signifying it is over extracted, I am using BDB's stock basket .
Today it was 17 gms in targeting 38 gms temperature at 203 , should I dose lower ? It seems the puck is not getting saturated in the preinfusion . Should I get a better tamper , I am using a pin to do the wdt which may mot be that effective.

pcrussell50

#4: Post by pcrussell50 »

The stock basket is good. Very good in fact.

For dosing amount... there is the "nickel" test*. Prep a puck and put a USA five cent bit on it and lock into the group. Unlock it and gently remove the coin. It should leave the barest indentation or none at all.

*Hopefully I have described this right. Feel free to correct.

-Peter
LMWDP #553

DamianWarS

#5: Post by DamianWarS »

vinodism wrote:Hello Everyone,
I recently got a BDB 920 and there is not for now. The blind max pressure is at 10 bars, and preinfusion set to 55, temperature 202 (the bean I am using seems light medium Colombian washed beans from Elm Roasters in Seattle),
https://elmcoffeeroasters.com/collectio ... an-caicedo
Flavors: LIMONCELLO, CARAMEL, ROSE.
I was dialing in with niche - 18 gms in and targeting 40, and I had to dial it quite fine than normally for other beans like Dolce by Vivace, so first shot around 12 on niche after recent calibration, at the given PI setting I see first drops around 15 second the pressure around that time for 5ish and it was a slow ramp up, I am using stock tamper and double basket. I got 40 gms in around 43-44 seconds and peak pressure after pre infusion was 9 bars.
The first shot lacked sweetness and I felt it was having some under extraction (I am quite novice but I felt the shots had sourness -may be fruity acidity can be perceived as sourness as the beans have listed limoncello in it but I was missing sweetness which was caramel and definitely no rose at all :D . So I thought may be there is some channeling because no distribution tool but I did some WDT with hair pin DIY and tamped gently doubting the tamper is not good enough so tamping hard may cause some channeling especially around the rim as it seems less snug.

So I moved the setting two notch finer( using the binary search kind of system) and this time again did same WDT and gentle tamp', this time I saw first few drops around 19 seconds and the ramp up flow was slower than previous. 40 gms around in 50 secnds and this time I thought to give analysis to the puck if it comes out clean, and I found that the puck actually stuck to the group and when i got it out it had serious dark color around the rim of the puck and there was lot less saturated coffee around middle lower portion. Definitely channeling !!

I have pulled decent shots on my expobar lever with e61 group head with the preinfusion that comes with e61 design, but never used pre-infusion as a variable before much may be just pre-wetting.

I would try again tomorrow from where I have started feels bad to waste such a nice coffee while dialing in :(

Here are my questions
What should be right temperature and PI value set based on light medium roast ?
Which tamper I should get for BDB which can stop the channeling from the circumference , I guess a leveling tamper would be better as that would remove some variability .
I was thinking to play with the stock BDB settings first before going to the needle valve mod.

Thanks for reading this long and somewhat unstructured post.


,
since you're into experimental things you might want to try using a paper filter in the PF. it's something Scott Rao and Matt Perger claim boosts extraction and allows you to grind finer. there's a phenomenon of fines migration during the shot that can lead to fines clogging the PF basket and the theory is a paper filter is going to prevent this. There's going to still be some kind of fines migration going on it just won't clog up the holes of the PF basket and the flow will be more consistent and typically faster (since the PF basket holes aren't clogged up). It can boosts extraction, prevent channeling and allow you to grind finer. Perger has a blog on it (no surprise) where he actually advocates for a double filter on the top and bottom, one on the bottom to prevent fines migration and one on top to prevent early erosion of the puck that can lead to channeling.