Results 1 to 12 of 12

Thread: Mr. Inconsistency

  1. #1
    Member
    Join Date
    Jan 2011
    Posts
    43

    Mr. Inconsistency

    Gene Cafe Coffee Roaster $850 - Free Beans Free Freight
    Hi

    Inconsistent coffee has been perpetual problem for myself for the last few years, I've kind of just rolled with the punches and made adjustments (usually until it was "good enough"), but I can't really tell what I'm doing wrong.

    For example, today I pulled a shot and the coffee came out so quickly it was like brown water, however the day before yesterday everything came together for the near perfect cup.

    I haven't changed any settings on the grinder, so am I right to assume that a day in the grinder has changed the bean?

    My questions?

    I've got a Mazzer Mini, do I need to have it filled to a minimum level to provide consistency, does the weight of the beans in hopper determine the quality of grind?

    How long can coffee keep in the hopper?

    What else do you check to know you're going to get a great cup?

    Thanks

  2. #2
    enjoy black coffee JamesM's Avatar
    Join Date
    Nov 2008
    Location
    Perth
    Posts
    672
    Hey ya, welcome to the journey of coffee, talk about unpredictable!

    First, your questions:

    1. you don't have to have coffee in the hopper, ever. I dose mine PER SHOT with a scoop. In fact, if you wanted, you could remove the hopper and use a cheap tamper or a blind basket to cover the throat
    2. just don't keep coffee in the hopper. If entertaining, you could fill it with however much you like and then remove it later that night. Or maybe leave it for the weekend. I don't recommend keeping coffee sitting in the hopper

    People will argue that it defeats the purpose of having a manual doser mazzer, which it does, but hey, we want fresh and consistent right?

    My questions for you:

    How old is the coffee, is it stale? This can make for inconsistent brewing

    At what time of the day did you brew yesterday? And what time of the day today? I ask because a brew in the arvo might require a grind adjustment compared to a brew in the morning. especially if your beans have been sitting in the hopper.

    Are the beans (in the hopper) exposed to sun?

    Where are you located? what is the weather like at the moment?

    Which machine are you using? Are you repeating the steps (including warm up time) for each brew?

    so many variables! So much great help here on CS to get you dialed in too

  3. #3
    Senior Member CafeLotta's Avatar
    Join Date
    Jun 2012
    Location
    Melbourne, Vic, Aust.
    Posts
    1,029
    You haven't mentioned which Coffee Machine you have? Are you using pressurised or non-pressurised filter baskets?

    Day to day inconsistency in brewing is largely due to variations in either technique, brew temperature, brew pressure, grind consistency etc.

    The differences you mention in brew flow rate are most likely due to technique - how full you pack your filter basket and how you tamp. This assumes you are using the same bean and grind setting as the day before. If you under-fill the basket you can easily get channeling causing a fast pour. Inconsistency in tamping pressure can also cause variations in brew rate. Check this video for one way of gauging tamp pressure - Making an Espresso - Tamp Pressure and Its Effect On Shot Timing - YouTube

    Many videos out there - just another - Make the Perfect Espresso Shot - YouTube

    As you haven't mentioned the machine you are using its hard to comment on brew temperature other than to say if its a basic machine, do a search on temperature surfing.

    Beans are usually at best to about 3 weeks after roasting. Exposure to air, light, humidity all lead to quicker deterioration of freshness and taste. I normally store beans in valved foil coffee bags and only put enough beans in the hopper for immediate use. Shops fill hoppers full due to high turnover I imagine. Doing the same at home with low turnover of beans probably isn't getting the best out of them and more than likely causing them to go stale quicker.

    As beans age over a week or two you may need to fine tune your grind to slightly finer to slow down the pour a little.

  4. #4
    Member
    Join Date
    Jan 2011
    Posts
    43
    Great advice thanks!

    It's a stop-gap Nuova Simonelli Oscar until I can get my hands on a Rocket Giotto or the like. I think I'll check out the links, it's been a while since I bothered to look at that sort of thing for a while.

  5. #5
    Senior Member Rocky's Avatar
    Join Date
    May 2008
    Location
    Central Queensland
    Posts
    1,085
    I produce the occasional sub-standard pour and it is because my machine is very sensitive to variations in dose and tamp.
    When I get these exactly right I get a great cup of coffee.
    Occasionally I will be aware that the machine has been hotter than usual during the pour, and again the pour will be sub-standard.
    I would imagine that some machines are more sensitive than others to minor variations in operator technique.

  6. #6
    Senior Member
    Join Date
    Jun 2007
    Location
    Sydney
    Posts
    723
    Quote Originally Posted by JamesM View Post
    Hey ya, welcome to the journey of coffee, talk about unpredictable!

    First, your questions:

    1. you don't have to have coffee in the hopper, ever. I dose mine PER SHOT with a scoop. In fact, if you wanted, you could remove the hopper and use a cheap tamper or a blind basket to cover the throat
    The problem with doing this is that the bean mass pushes down the beans which are touching the burrs, leading to a more even grind (less popcorning) and fewer fines. Having a couple of hundred grams of beans or so (depending on the grinder) avoids this phenomenon, leading to a more repeatable shot with higher clarity.

    2. just don't keep coffee in the hopper. If entertaining, you could fill it with however much you like and then remove it later that night. Or maybe leave it for the weekend. I don't recommend keeping coffee sitting in the hopper[/quote]

    I prefer tinted hoppers (less UV) and the grinder/beans to be kept out of the sun. Changes to weather will affect the coffee - roasted coffee is hydroscopic, so running a dehumidifier or keeping your hopper well sealed is a good option. Coffee stales over time and can lose moisture content as it dries out, so over the course of a few days, you should be altering your dose amount and grind to compensate.

    People will argue that it defeats the purpose of having a manual doser mazzer, which it does, but hey, we want fresh and consistent right?

    Not sure why? You can easily grind through the doser (some americans know this as being a "thwacker"), and the doser breaks up clumps, is usually ground (reducing static electricity)
    My suspicion (and it's just a suspicion) is that distribution may be a factor - are you overfilling and then levelling off with a straight edge, spreading in a circle using your thumb on it's side, or something else? A bed of coffee that's tapped three times to settle it might end up with an extra gram of coffee in the portafilter when filled to the same height with no collapsing, or even more. Combined with edge channeling (are there any holes in the puck) and/or puck fracturing (caused by hitting the portafilter off stuff post-tamp), this can be the difference between choking a shot and running a gusher.

    hope that helps!

    CH

  7. #7
    enjoy black coffee JamesM's Avatar
    Join Date
    Nov 2008
    Location
    Perth
    Posts
    672
    I've not noticed (by sight or taste) any difference in dosing a mazzer one shot at a time, or having the "weight" of a bag of beans in the hopper.

    Maybe there's some scientific study in to this somewhere about the place.

  8. #8
    GRB
    GRB is offline
    Junior Member
    Join Date
    Nov 2005
    Posts
    25
    I did some measurements a few years ago. Certainly not conclusive but...

    Commercial link removed per the http://coffeesnobs.com.au/general-ne...icy-rules.html
    Last edited by Javaphile; 1st February 2013 at 02:37 AM. Reason: Commercial link removed

  9. #9
    Senior Member
    Join Date
    Nov 2006
    Posts
    979
    It definitely has an effect. If you throw 20gm of coffee in the throat, compared to having a hopper with 100gm (which seems to be enough to avoid the effect) then I have noticed the need for a finer grind. It's even more obvious on large conicals like Roburs where you start getting gushers if the beans get below the level of the hopper. As far as taste goes I'm not sure its a discernible difference, if it is, its not huge.

  10. #10
    Senior Member
    Join Date
    Nov 2006
    Posts
    979
    My advise is to make sure you are getting a consistent weight of coffee in your baskets. For consistency you want to have your dose accuracy to with 0.5 of a gm. This is the most important thing that effects consistency.

    Also you might be having issues with channeling and uneven distribution causing the water to flow faster through one part of the puck while not extracting the rest.

    Make sure you give your portafilter one good tap to settle the grinds (more taps make dosing accurately harder) and then distribute by levelling off. Also make sure you tamp down on a solid surface to get around 5-10kg of pressure and make sure your tamp is even.

  11. #11
    Senior Member CafeLotta's Avatar
    Join Date
    Jun 2012
    Location
    Melbourne, Vic, Aust.
    Posts
    1,029
    Quote Originally Posted by soccerstuie View Post
    Great advice thanks!

    It's a stop-gap Nuova Simonelli Oscar until I can get my hands on a Rocket Giotto or the like. I think I'll check out the links, it's been a while since I bothered to look at that sort of thing for a while.
    Judging by the reviews available on-line for the machine you have, it is a very capable unit. Temperature stability shouldn't be an issue due to its boiler size. It was mentioned in a couple of reviews that between 15-30mins warm-up is required.

    Just aim to nail your consistency with grinding, filling basket and tamping and hopefully it will all fall into place.

    After this if you want to really be sure you are getting the most out of your machine, have a reputable service centre check the brew temperature and brew pressure to make sure they are where they should be. Apart from that your machine is more than capable of producing a decent brew.

  12. #12
    Member
    Join Date
    Jan 2011
    Posts
    43
    Behmor Brazen - $249 - Free Freight
    Thanks for all the comments, I can definitely take away from this, I feel confident I have a few tricks to try now. Much appreciated.



Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •