Yellow substance remaining in basket

[Dazzler]

Hi snobs
I often see a yellow substance remaining in the basket after I knock out the puck. What is it please?

[>JetBlack_Espresso]

Re: Yellow substance remaining in basket

coffee oil. Youll see more as your extraction gets tighter.

charlie

[Dazzler]

Re: Yellow substance remaining in basket

Thanks for the reply, so this is normal?

is it in any way an indication of. . .
- grind too fine or coarse
- pressure too high / low
- temperature too high
- over or underfilled basket
- beans too old / young

There are so many variables, Im just trying to better understand whats happening in the espresso process.

Thanks again

[TC]

Re: Yellow substance remaining in basket

Its generally either too fine or an overdose. You might observe choking and bitterness assocoated with this shot.

[Dazzler]

Re: Yellow substance remaining in basket

OK, I suppose it was a little bitter, but I am a latte drinker normally and my cup is better than my local cafe already.

anyway, I have gone 1 notch less fine on my Mazzer, keeping all other variables constant...
Result, coffee is still way better than my local cafe (but still not as good as my favourite cafe). It pulled less pressure (now 10 Bar instead of 11) it may have been less bitter and there was no yellow residue. The 30 Ml shot was in 25 seconds.

Cheers and thanks for the help.

[WantRancilio10]

Re: Yellow substance remaining in basket

So... I upgraded from an Isomac Venus, which was great, to a Zaffiro... and now I’m uh a little underwhelmed... DOH!!

I’m making a consistent shot... consistently dull!

Like the OP I’ve also got coffee oil residue in the basket... and not just when I’ve overextracted/overdosed. It’s there when I’ve pulled 60ml (double basket) in 30 seconds and even, to a lesser extent, when I’ve pulled 60ml in 20 seconds.

My current beans are a bit stale (a terrible admission) but they’re the same beans I used to good effect in Venus when I decommissioned her a few weeks ago. Is an E61 group head machine likely to be less forgiving?

Welcome thoughts on the problem and solution. Obviously the residue may provide a clue to the ‘dullness’ of my shots or it could be a red herring.

Could it be... Machine too hot? Or pressure too high? These would require adjustments that I think are relatively simple if you’re a domestic mr_fixit. I’m really not much of a mr_fixit – should I take it into the experts (Cosmorex Coffee)? Coffee oil residue oxidising inside the Group? The machine is two years old and spent the last year in a box. Better spend some time looking behind the shower screen?

[Barry O'Speedwagon]

Re: Yellow substance remaining in basket

My current beans are a bit stale (a terrible admission) but they’re the same beans I used to good effect in Venus when I decommissioned her a few weeks ago. Is an E61 group head machine likely to be less forgiving?

Might be an idea to try some fresh beans first (partic as the coffee apparently tastes crap)...this would eliminate one variable? I only get a touch of residue in the basked when Im dialling in / adjusting for ageing bean and have the grind too fine (and yes, it an E61 group head)...but seems more sensitive to this as beans age.