High pressure, under extraction

I have a breville barista express

I have been fine with extractions so far with the exception of one bag of beans that I purchased from a local roaster. The beans are very light roast (possibly cinnamon) and they are chubby (wider than long). My issue is this: pressure is high, but it’s always underextracted with very little pale crema and highly acidic taste. Increasing fineness does not help–it simply stops flowing at a certain point without solving the issue. The flow is watery and very thin no matter what I do. Any suggestions on how to proceed? All other beans I have used are great.

Thanks, I searched and didn’t find anything like this so hopefully this is not a duplicate question.


How long did you let the machine stay choked during your finer extractions? I tend to pull very good shots even after a 5 second choke. By the way, if you time your shots, convention has it you include this duration; when your pressure is on but no espresso has come out.

It might also be that, especially if you have a stepped grinder, the ideal grind for this particular bag falls in between the steps available to you.

Hi Farad,

if the beans are ‘chubby’ and small, they sound like they might be a denser bean. If so, I would suggest that you play with your recipe a little. If you want to stick with the finer grind size to maximise extraction of the seemingly dense beans, then perhaps try lowering the dosage of your dry coffee. Alternatively, you could have a go at making the grind size coarser and increasing the dose, but you may still end up not achieving the best with your coffee.

Just a couple of suggestions :slight_smile:

Hi @fizaddou,

I’m curious about these ‘chubby’ beans…? Any other information that you can share? (origin, varietal, roaster, etc.)?


I wouldn’t stress about your parameters/equipment/technique- it sounds like a classic case of the roast being very under developed and there is nothing you can do on your end. Your roaster needs to drop his beans a few degrees higher and possibly extend the roast.

And the reason I am confident about this is that I have made this roasting mistake a few times when I was learning :wink: