pre infusion in relation to beans etc

Cuprajake

hi all,

ive often wondered what a desired range for pre infusion seems to be, be it the ramp up of a pump, line driven etc.

ive looked for articles and seen bits, but does anyone have any good insights - videos to do with it:

do you like a quick infusion or 30 second drips, i remember a decent vid on the slayer saying long slow gives uneven extractions as you have a wet top and dry bottom,

then theres pressure 1 bar up to what 9 bar…

is it bean specific, grind/tamp specific, does it have more effect than temperature??

input

Emc2

Cuprajake not sure where I came across this technique. It seems to work fine. I use the flow regulator on the Bianca. I turn the paddle to about 7 o clock, run it till I see the first drops, turn the paddle off for about 5 seconds and then slowly increase the flow till the pressure reaches 9 bar. With my current grind setting, the preinfusion pressure is about 4 bar. This changes depending on the bean and grind size.

DavecUK

I find bitterness can be a limiting factor.

tompoland

Scott Rao’s “Blooming Espresso” preset on the Decent is designed for light roasts and has a 39 second pre infusion phase. Rao also designed the “Adaptive” preset for medium roasts and pre infusion is 10 seconds.

Not sure if that is helpful or not and I can’t tell you the science behind it other than to say that Rao measures TDS with a refractometer a gazillion times to optimise the presets.

Me, I just taste it. 😋 😁😉

MWJB

tompoland Rao measures TDS with a refractometer a gazillion times to optimise the presets.

Me, I just taste it. 😋 😁😉

Extraction is a guide to efficiency, within the confines of origin (biggest variable), rather than taste/preference, so you always need both & Rao is clear about this. You only need to take 1 sample per brew, all in takes about a minute, but you can busy yourself doing other things so you don’t need to dawdle (and of course, you don’t need to measure if not for a specific test/dial in).

I believe it was Jonathan Gagne who developed the Decent adaptive profile.

Cuprajake

Yeah I’ve seen a presentation from him regarding extraction which was very interesting

Cuprajake

-Mac

So is there a database available for beans with their ‘best’ TDS number?

CoyoteOldMan

-Mac So is there a database available for beans with their ‘best’ TDS number?

I suspect not… not least because just TDS is incomplete information. 300 mg/l of MgSO₄ has quite a different taste from 300 mg/l of FeCO₃ + H₂S

-Mac

And why aren’t roasters giving the values for what they think their beans taste best at?

Cuprajake

I prefer the taste of C12H22O11

Haha

It’s hard to explain what the pr infuse does, by the looks

I have it across two forums all full of very knowledgeable people and there’s very little in the way of an answer.

Then you add a grinder as a variable, and roast etc

You could grind two batches of the same bean, same roast do the extraction identical and get different results

So is infusion under 3 bars just pre wetting and above extraction 🤷

For perspective 3bar is 3stone of pressure per square inch.

I kinda got lost down this when I was looking at difference in burrs

CoyoteOldMan

Cuprajake What about C₁₂H₂₂O₁₁ + CH₃CH₂OH + HOC(CO₂H)(CH₂CO₂H)₂ + C₁₀H₂₀O in aqueous solution?

LMSC

CoyoteOldMan C12H22O11 + CH3CH2OH + HOC(CO2H)(CH2CO2H)2 + C10H20O in aqueous solution?

Giphy - Jimmy Fallon Dont Ask GIF by The Tonight Show Starring Jimmy Fallon

🤣

CoyoteOldMan

LMSC It’s as close as I can get to a mojito (sugar + alcohol + citric acid + menthol, in water).

🥂

Cuprajake

I used to do something similar with my Bianca.