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Coffee making - the perfect grind!

I have a Breville dual boiler coffee machine, BES920, which is now a year old - it replaced the same machine which we had for 6 or 7 years so I consider I know what I’m doing and what to expect.

I was always happy with the what the first machine produced - coffee tasted good and the leftovers (for want of a word) would fall out of the portafilter in a nicely formed, relatively dry shape - easy to dispose of. The newer machine makes quite different coffee, (though the taste is OK), very sloppy leftovers which can’t be disposed of in a knock box (goes in all directions) and which doesn’t seem to affected by brand or grind.

I complained to Breville early in the piece - we had numerous phone calls discussing how things should work and the fact that the machine never got anywhere near the required pressure (between 8 and 10 on this machine) on the pressure gauge and the machine was replaced - the replacement isn’t any different.

So I think my questions are quite specific -

  1. what determines the consistency - dry and formed OR sloppy - of the leftover coffee? I would think the grind would affect this but this doesn’t seem to be so.
  2. what should the should the pressure ideally reach? The needle always wavers just below the ‘8’.

Any suggestions about what I can try will be welcome.

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@RebeccaCiaramidaro from Choice may wish to respond.

I suspect you are familiar with the normal tips.

From personal experience (Sunbeam EM7000) the grind and quantity are closely related. If you go coarser try putting in more coffee and vice versa. 9 bars is often cited as ideal in a general case assuming your gauge is calibrated. A fine grind might get you 9 bars but if there is not enough coffee in the basket the puck will float up and stick to the shower screen or be muddy. If that happens go slightly coarser with more coffee and a firmer tamp to maintain the pressure.

There are some who suggest putting a small coin sized object (or clean coin) on the top of you coffee, inserting it into the machine, and removing it, should yield an indentation of the coin. Alternatively there should be evidence of the screw/indentation of the shower screen. If it does not you are not using enough coffee regardless of grind.

If you still have your old machine parts compare the portafilter and basket. From experience even different hole patterns on the coffee baskets can have subtle effects and manufacturers change some things just because they can or because a different process might save a cent in manufacturing costs.

I have a Eureka Mignon grinder, not so well reviewer by Choice, but instead of click stops it has an infinitely variable adjustment, and as the humidity or temperature changes a nudge one way or the other has worked magic.

YMMV.

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Hi @Rel and @PhilT

I’ve spoken with our tester and the most important thing to play around with would be the quantity and grind that you’re using. We have experienced similar issues during testing but once an extra gram or so was added it fixed the pressure issues. The only thing to be careful about is that the extra coffee grind might cause the coffee to be burnt as its being extracted and lower the taste quality of the espresso.

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As for your sloppy pucks, it’s usually adjusting one of your variables…amount of coffee or grind size (whilst keeping your tamping pressure consistent). This is turn will affect your pressure reading. So if you have way too much coffee in there and it is a fine grind, the resistance will be high and your machine will battle to get any water through it. I had a similar problem and found I wasn’t using enough coffee. And just remember to vary one element at a time.
Watch James Hoffman on Youtube…very informative! He likes to precisely weigh his coffee so he has that one variable under control.

What makes for a “sloppy” is the gap between the top of the tamped surface in the basket in the portafilter and the shower rose of the group head. If it really bothers you, get some coffee scales and start with your regular shot - weigh it. Then, add more coffee (say, 0.5gm). Keep re-doing the shot with additional increases in shot weight until the sloppy puck disappears. At this point there will be no gap between parts mentioned earlier. Now, two words of warning–if you overfill the basket, when you lock in your portafilter you will add pressure to the shot (compressing further an already tamped shot), and you won’t get your desired “mouse-tail” pour. Also, as you incrementally add coffee to your basket, you will probably have to back off the grind as it will become too fine for the shot volume. Coffee machines vary but your instructions should tell you the time and volume for a good pour. A barista using an E61 group head, (cafes and high-end home machines) aims at 30 seconds for 30 mls. (Double shot - 60 mls in 30 seconds). This gives that mouse tail pour. Experiment to see what ideally suits your machine but be in control of your variables (weigh of coffee in the basket @ what grind). Hope this helps.

Thanks Phil.

You’ve reminded me what the leftovers should be called - puck ----

My questions were

So I think my questions are quite specific -

  1. what determines the consistency - dry and formed OR sloppy - of the leftover coffee? I would think the grind would affect this but this doesn’t seem to be so.
  2. what should the should the pressure ideally reach? The needle always wavers just below the ‘8’.

Re 2 above - the gauge shows a black section which seems to be
This machine comes with a gadget which trims the top of the dry coffee so it isn’t overloaded and that means that the pattern of the shower screen won’t appear - to the extent that if it is overfilled the coffee dribbles out and produces a very small amount.

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I hope this reply can be seen by all those who responded - PhilT, Suzique, Rebecca and BassaJack, thanks for your suggestions, it will take some time to try all those suggestions and see how they go. Much appreciated.
Rel

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