If this is your first visit, be sure to
check out the FAQ by clicking the
link above. You may have to register
before you can post: click the register link above to proceed. To start viewing messages,
select the forum that you want to visit from the selection below.
For the last few weeks I've been doing daily compare contrast of a 9 bar extraction on my Rocket Apartamento vs a manual espresso press I have with a pressure gauge @ 6 bars - lighter roast single origin coffees and turbo style shots 1:2 - 1:2.5 kind of ratios. And more often than not, I'm finding I prefer the shot @ 6 bars - for me, I'm finding it often brings out more brightness and clarity in flavour. This is using a Niche Zero grinder.
Watching this thread with interest. I think I"m close to 6 bar than 9 bar when I pull a shot with the Stietman but with no gauge (and I don't want one) it's impossible to know for sure. The Argos is coming out with 6 and 8 bar spring options so obviously Ross must like having a 6 bar option. Personally I have no idea what diffference it makes which is why I'll follow this thread with interest.
My standard (favoured) pull on a Cremina starts around 7-7.5 bars and hovers in the 6-7bar region for the first 10 seconds or so (I have a pressure gauge installed). For some beans I use a tighter pull. From muscle memory, I reckon that my favoured pulls on the Flair are in a similar range.
Some months ago I replaced the vibe pump in my old Faema E98 with a variable speed gear pump, which allows me to manually control the flow/pressure. Since then I've been mucking around trying a variety of pressures and pre-infusion times. I've pretty much stopped pulling shots at 9 bar, because I've found that I'm getting consistently nicer shots at 5 to 6 bar.
Using my favorite darker roast Blacklist Queen Bee beans, I've been grinding finer, with a longer 12 second pre-infusion, and extracting at a shorter ristretto-like 1:1.25 ratio, (16 grams in the basket, and 18 -20 grams in the cup). While it has lost a bit of the usual darker-roast chocolate, it has been replaced with some very interesting sweet, fruity, ands malty flavors which I prefer. More importantly, the wife has given it the big tick of approval, and often comes back for a second cup straight away.
Here's the caveat - this is not a sweeping endorsement of 6 bar for everything or everyone. It's based on my limited experience and specific set of circumstances. Also note that I haven't had a play with the lighter or medium roasts yet, so can't comment on how that plays out at 6 bar. But I very am interested to see what other people have to say, especially the lever machine cohort.
I was also expecting Decent owners to chime in here, with some comments on lower pressure profiles. Someone must have had a crack at it, and have an opinion. . . . .
Yeh, but you've changed 2 things at once: 1) pre-infusion time, 2) pressure. You'll find that a lot of that difference in flow rate is coming from the pre-infusion.
@FilthyStudio 9 bar is a bit old school now, it’s still common but the higher end cafes are testing this. Pressure and preinfusion do two different things. Pressure is more related to strength and preinfusion is more related to sweetness
There's no magic here. If you're using light roast; only applying 6bars will mean it's more likely you're NOT getting channeling and thus a more even extraction and thus better flavours. GS3 guys been doing it for longest time - instead of going higher and higher doses or grinding finer and finer, they realise they can just reduce the amount of pressure they're blasting the puck. If you google you will find Hoffman talking about the history of why 9bar and given what we know today....it's not necessarily the best thing. It's also why levers were popular...it didn't blast 9 bar constant at the puck. It's also part of the reason pre-infusion works....it wets the cake, give coffee time to build up resistance before you blast 9 bars at it...and reduce chanelling. That said...it's just another variable one can play to maintain puck integrity during extraction.
Some light reading on the subject: https://strivefortone.com/2016/03/27/this-low-pressure-lark/ https://strivefortone.com/2016/05/18/this-low-pressure-rehash/
Ta, I've seen that some months ago when I was trying to work out the variable speed/pressure stuff. Although this link is from 11 years ago, it makes sense compared to what I'm seeing, especially the use of lower pressure and a slow ramp-up.
"Bean" extracting at around 6 bar on a Cremina for about 5 years now, (9 bar extractions on a Cremina are near impossible for old farts).
Best coffee's we have ever tasted period.
A lot of us started with 1-2 Bar using a French Presse, 4 minutes and a coarser grind - wonderful coffee's, but completely diffrent extractions for exactly the same roast.
Point is the amount of bars you decide to use is part of the vast palate including temperatures and grinds to zero in on the tastes you want to bring out in that particular Coffee.
Best Yemen we have ever experienced has been from a French Presse at 1-2 Bar.
No rules here - just enjoy the differences.
Comment