Jump to content

Recommended Posts

Sorry for the title but it describes the phenomenon of a seemingly blocked pour. This has happened randomly (maybe?) around five times now and I do not understand how it happens.


I carry out a normal 18gm shot using freshly ground beans. It is tamped as normal and takes 25 seconds to produce a good looking shot. I immediately dump the grounds and wash out the portafilter which is immediately put in the E61 and the group flushed until clean. I then dry the portafilter and grind a new 18gm load into it. I finger level and tamp with my usual 30lb (or less if I'm expecting this problem), set the timer to 25 seconds and start it and the pump.


I wait, and wait, and wait, perhaps for up to 10 seconds before both PF nozzles start to slowly drip like black oil. The drips do eventually turn into a pour with the correct colour and after a total of possibly 40 seconds or more seconds I stop the pour.


Regardless of whether this turned out to be an acceptable taste, which it sometimes does, I really need to understand why this is happening and when it does its always immediately after a normal pour?


During the first or subsequent pour the brew pressure as indicated by the gauge has never dropped below 10.5Bar


As I need to keep the hair I have left I really would appreciate any advice.

Link to post
Share on other sites

With my mini-e I found this (especially as the grinds back up inside the chute behind the grid)


as an example, grinding until nothing left in hopper/throat


Shot 1. Throw 18g in hopper. grind. 16.7g in portafilter. 1.3g in chute (if I didnt brush it out then....)

Shot 2. additional 18g in hopper. grind. approx 17.5g in portafilter 1.8g now in chute.

and so on.


Removing the grid and brushing the chute clear , meant 18g in 18g out....& shot consistancy

Edited by garydyke1
Link to post
Share on other sites

I think Gary is referring to the practice of weighing the beans prior to grinding and then grinding only those beans. This is achieved by keeping the grinder empty and then only filling it with the weighed beans each time you grind.


Sometimes people who single dose grind (grind just enough in the grinder for the drink they are about to brew) overlook weighing the coffee coming out of the grinder because they have already weighed the coffee going in. Unfortunately, most grinders retain some of the ground coffee after grinding (some a lot more than others). This means it is necessary to weigh the coffee coming out of the grinder as well as the coffee going in and sometimes it may be necessary to grind slightly more than needed to allow for the retention inside the grinder.


A further problem with grind retention is that those retained grounds will probably come out of the shoot as part of the grind for the next drink. If the next drink is sufficiently in the future then those retained grounds will probably be stale and so behave differently during brewing. To counter this, many people chuck a few g of sacrificial beans through the grinder prior to grinding to purge any stale retained grounds.

Edited by jimbow
Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • About
    Coffee Forums UK is the UK's premier coffee forum Started in June 2008 by Glenn Watson, we now have more than 24000 mainly UK based members, and welcome more than 3000 members and visitors from around the world each day! With strategic investment and digital expertise from the Jackson Lockhart team (Tait Pollack and Adam Bateman), we are taking Coffee Forums UK to the next level, and are delighted to share the journey with you.

    New Members:
    We are often referred to as the friendliest forum on the web and we look forward to welcoming you onboard. Please read our Terms of Use. We stick by them, existing members please familiarise yourselves with them.


    Coffee Forums Media Kit

    Click Here To Buy Advertising Space 
    £100 p/m when paid yearly, up-to: 690000 banner impressions per month!

    Donate / Sponsor

    Get Your Supporter Badge Today (per year)


    Coffee Forums Logo

  • Create New...