Coffee grounds in espresso

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Posts: 7
Joined: 15 years ago

#1: Post by zanis »

Hello all,

I have just started on the wonderful path of creating my own morning coffee instead of paying someone the honor of getting it wrong.

I have a Iberital grinder (burr-grinder) and a Diamond Italia (vibrating pump) espresso machine. I am very detailed on cleaning the machine after each use (previous life as a chef) and using only the freshest beans I can get - normally less than 2 weeks after initial roasting.

I have spent many hours getting the grinder just right for extraction but of late I am noticing very fine coffee grinds in my espresso shot. The coffee is great tasting but the grinds are a worry.

i am not sure what I am doing to get the grinds in the shot. Here is what I have been focusing on:

1) Cleaning the machine every time I use it - including weekly backwash (?) cleans with the special cleaning product.

2) Balancing tamp pressure with grind.

3) Making sure I only extract for less than 25 seconds (sometimes I go to 28 seconds) to get the good crema.

4) Making sure the portafilter is tightly secure within the group head.

Can anyone point me to what I could focus on. I am mindful of increasing the coarseness of the grind as the espresso shot looks like it is suppose to. Maybe thats what I should be looking at - though I think that will really upset the extraction time.



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Randy G.
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Joined: 17 years ago

#2: Post by Randy G. »

Possible Sources of grounds in the cup:

- through the basket's holes - This would result in fines in the cup possibly from worn burrs or a worn basket.
- through the basket - Possibly a crack?
- from around the outside rim of the basket on the portafilter body - Could be left over grounds vibrating off the PF.
- from the bottom of the PF - tamping on a surface with loose coffee on it transferring grounds to the spouts
- from your hands - if you have some loose grounds on your hands, when you reach over to turn the machine on or lock the PF in place.
- coffee dust fairies - no explanation needed. - 2000-2023 - a good run, its time is done

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Team HB
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Joined: 18 years ago

#3: Post by RapidCoffee »

Randy G. wrote:- from the bottom of the PF - tamping on a surface with loose coffee on it transferring grounds to the spouts
Other than coffee dust fairies, this is the most likely explanation: grinds that adhere to the bottom of the basket and/or portafilter during shot prep.

zanis (original poster)
Posts: 7
Joined: 15 years ago

#4: Post by zanis (original poster) »

Hello thank you for your replies.

The grinder is brand new - less than 3 months old and gets used maybe 4 times a day max. The machine and PF are brand new as well and I have checked the PF for cracks. I now also make sure that the tamper mat and PF are free from grinds before making the shot.

I think it could be grinds at the bottom of the PF so I will soak the PF in the coffee machine detergent every night like I read in an article on this awesome site. I clean (backflush?) the machine each week so that should be free from nasties.