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  • #16
    I also agree that your shots are gushing; looking at the pours I would think that the coffee would have to be sour, nasty, right at the front of your mouth.

    If you use the technique that Andy posted (#10) and choke the shot so that it only drips (cut the shot at about 10mls) then taste the coffee,
    no matter what the roast, it will be bitter, sitting right at the back of your palate, in a very unpleasant manner.

    Then, as Andy says, back your grind off, a little more coarser, until you find the zone.
    Check the link that Mal posted, they're pretty good and do some searching on the tube using parameters like ' perfect espresso pour ', 'good espresso pour',
    and 'techniques for good espresso'. You will get plenty of visuals on what a good pour looks like. Also add the name of your machine and see what youtube has.

    Chris (Talk Coffee) told me, when I was first learning about espresso, that a good pour was like a " drip that wants to pour".

    Don't discount anything in the process, dose and tamp has been mentioned, water that isn't at the right temp, (too cool) and as Flynn has mentioned above,
    try another bean and ask for an espresso roast, make sure it's not a filter roast, which will be sour. However the roast is the last thing to consider as you have some work to do
    getting the pour right first.

    When taking video, include the spouts on the group handle so the start of the pour is easily seen, it's easier for you to get helpful advice if your whole process is visible.
    Flynn's suggestion of uploading your grind/dose/tamp is a good one.
    Although a naked p/f are great for diagnosis, they are by no means essential.

    cheers

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    • #17
      *grins* Couple of those shots I wanted to call, 'Thar she blows Cap'n!'

      I seem OK with shots - I grind 1 notch finer (really have to get to do Ray_C's fix on my EM0480) and tamp a bit lighter. That seems to make dose more sensitive in that if I over or under even slightly the shot isn't particularly good. I like my macchiatos and bitter or sour in one of them is obvious, so I did quite a few attempts to work out my machine. At the end I was getting passable shots even from Coles Vittoria beans. (my version of sacrificial beans while I was learning )

      On your machine, is that gauge water temp or pressure? I'm guessing temp as it drops a bit as you pour a shot. Could you pour some water and measure the temp to see what it is when it's 'in the zone'?

      Comment


      • #18
        I did an experiment, finer and lighter tamp, and coarser and tighter tamp. Dose about the same. Both poured about the same. Coarser one tasted better, less bite. Both weren't too bad though. You need to spread it around in your mouth a bit too. I'll often also find if I am pouring into two cups, one will usually taste better than the other - I suspect unless your distribution is perfect, one side will always have more channelling/faster extraction than the other. I made some videos but the lighting is terrible so I won't bother posting them.

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        • #19
          @Darkfalz - here is the puzzle. Look at your double spout PF. Think about how the coffee goes into the bottom of the PF through the filter. Now ask yourself, how is it possible that one side of the double spout could possibly get a preferential version of the pour. The distribution affects the water travelling through the grind, but it is extremely unlikely to affect what goes into the 2 cups. Unless you have a very unusual PF, whatever comes from the basket drops into a common chute which feeds out into 2 spouts.

          Maybe check the level of your machine?

          As for lighter and finer... my version of that has been changed by TampIt's suggestion to do graduated tamping. When I ground a full basket and tamped at 15kg (give or take) was prior to me experimenting with grinds for espresso shots. When I say I grind finer and tamp lighter I am talking about moving (for my current beans) from a 13 to a 12 and tamping 3 or 4 times as I fill the basket and at finger pressure tamp levels. i.e. I rest my fingers around the top of the PF so I know how level the tamp is and then I give a slight pressure with the palm of my hand. I also finger-tap the PF to approx level the grind before I tap & tamp. For the final dose, I use the tamper (why do people bother with knives/popsicle sticks/flat edges when you can just rotate the tamper across the top of the basket to level the grounds?) to level it, tap it once and then nutate-tamp and tamp at about the 3kg level.

          If I forget to adjust the grind, I just lean on the tamper a bit more to get the nice shot I like.

          Oh, and I get dark beans. I just recently bought some mediums because of what I read on here that implies I can learn more about my technique by changing my beans.

          Comment


          • #20
            Originally posted by Journeyman View Post

            As for lighter and finer... my version of that has been changed by TampIt's suggestion to do graduated tamping. When I ground a full basket and tamped at 15kg (give or take) was prior to me experimenting with grinds for espresso shots. When I say I grind finer and tamp lighter I am talking about moving (for my current beans) from a 13 to a 12 and tamping 3 or 4 times as I fill the basket and at finger pressure tamp levels. i.e. I rest my fingers around the top of the PF so I know how level the tamp is and then I give a slight pressure with the palm of my hand. I also finger-tap the PF to approx level the grind before I tap & tamp. For the final dose, I use the tamper (why do people bother with knives/popsicle sticks/flat edges when you can just rotate the tamper across the top of the basket to level the grounds?) to level it, tap it once and then nutate-tamp and tamp at about the 3kg level.

            If I forget to adjust the grind, I just lean on the tamper a bit more to get the nice shot I like.

            Oh, and I get dark beans. I just recently bought some mediums because of what I read on here that implies I can learn more about my technique by changing my beans.
            Hi Journeyman

            Just a couple of minor points & clarifications.

            It has always been called progressive tamping in anything I have ever read. I am not a stickler for jargon, however another CS'r trying to look it up online as anything else may find it unobtainium.

            The best starting point on tamping I have ever come across is still Mark Prince's semi-abandoned 2006 effort (no part two yet, AFAIAK)

            CoffeeGeek - Tamping Science, Theory and Practice, Part One

            Careful reading of the whole article plus all associated comments (esp. Tim Wendleboe's insights) can really show the amount of havoc / disagreements / differing methodologies etc. I have posted somewhere on CS that IMHO matching each one of the various methods to specific roasts is a worthwhile exercise for those with time on their hands plus satiable curtiosity (Winnie the Pooh). Probably goes a long way to explain the minefield of disagreements.

            The ONLY (virtually) universally accepted factors amongst those "in the know" is:-
            1) NEVER tap to settle the coffee. It creates gaps between the grounds and the basket and promotes channelling. From my direct experience, VST baskets have a particular hatred of tapping, and it often leads to inconsistent coffee. Assuming the grounds are dry & fluffy, even a gentle side to side shake is often enough prep to be capable of easily tamping it level. If you must spread it evenly, use anything that can do it whilst maintaining a (fairly) level surface to tamp later. FWIW, on the rare occasions I bother to do so, I use a "one off" plastic CD case from years back which happens to be flat at the "bottom" and almost exactly the correct curve for circa 10% underdosing at the "top". If I ever felt the need, I would make the bottom around 57mm long so it would go inside a 58 basket allowing me to level out the grounds further down. That would help when using grinders that throw badly enough to need it (mine don't, or they recalibrate / disappear rapidly). These days I mainly use it when dialling a machine in to set a precisely known underdose (at whatever real percentage the thing actually is).
            2) IF you are going to polish the puck just before loading it into the grouphead, do not put any downwards pressure on the tamper. Just spin the tamper and let its weight do the job. Putting downwards pressure on it whilst polishing is called "tearing the top of the puck". It also creates channelling, and VST baskets specifically will react very badly to it...

            Those two factors are probably the two most common snafu's I see commercial baristas make. If the same baristas used a naked p/f it would spray everywhere. Strangely enough, I have never seen a culprit "go naked". Wonder why?

            A little more about VST's: Always get the ridgeless baskets. VST would probably not even make ridged one based on their own research papers if LM had not sponsored them historically. VST baskets hate tampers with a curved bottom. Must be a flat bottomed tamper or it fouls up the flow of the coffee. VST actually state this at some length in one of their publications. Kinda explains why so many CS'rs have issues with VST baskets, doesn't it?

            An experiment a day ....

            TampIt

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            • #21
              I'll try not tapping and see if it improves the flow. It's a light tap I use anyway as I noticed a heavy tap disrupted my nice lightly-tamped puck. But the tap I was doing was not after my final tamp, it was to settle the newly ground pile into the filter. Then I tamp it.

              I've seen (but never done) some coffee makers bang their PF solidly on the bench - maybe they don't have my miserliness about watching my hard earned coffee grounds spray across the bench.

              The finger tap I mention is just a gentle tapping on the side to get the dome to even out after grinding, then a light tap on the mat and tamp it.

              Something I've wondered about; should I polish after each tamp? I've been tending not to because I thought it might create planar surfaces deep in the puck rather than allowing a smooth transition between tamped amounts. I learned the no-pressure-polish thing very early on when I noticed the difficulty I was having keeping my coffee level if I spun the tamper while under pressure. It was much easier to tamp level then spin the tamp than try to keep a rotating tamper level.

              Interesting read on tamping. Mind you, his one about the God Shot was pretty informative - must go make a coffee...

              Comment


              • #22
                I've tapped my Group Handle while dosing for the last 10+ years and never experienced the problems touted by the so-called gurus...

                Mal.

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                • #23
                  I tap lightly after the levelling pre-tamp, but not the final tamp.

                  The most important thing about polishing, imo, is that turning the tamper before you lift it stops any coffee sticking to the underside of the tamper, leaving craters in your puck.

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                  • #24
                    Why tap after a tamp? What result do you think it has?

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                    • #25
                      Tapping after the tamp is definitely not helpful. Ive cringed a few too many times at various cafes as baristas tamp and either tap or bang the side of their porta for god knows why.
                      Before the tamp is ok
                      I am a huge fan of a naked portafilter- it sheds light on your tamping technique (not level, angles etc)
                      Tamping consistency is something thats comes with practice. Ive been taught to bend the elbow and have my upper arm at 90 degrees. I can then successfully push in a downward motion to tamp as level as i can. I slight polish without pressure then off the pull the shot.

                      I havent really read through previous posts so i might just be repeating others. Anyways keep practicing, reading and learning! Theres always more to learn.

                      A video on your tamping technique and dosing may help us identify any necessary changes?

                      Comment


                      • #26
                        Hi toomanyhobbies

                        What is the brew pressure reading on your machine when your shot starts flowing? If you have a gauge

                        Comment


                        • #27
                          Originally posted by Journeyman View Post
                          Why tap after a tamp? What result do you think it has?
                          My pre-tamp is just for distribution, it applies no pressure, just the weight of the tamp.

                          Comment


                          • #28
                            Originally posted by Journeyman View Post
                            I'll try not tapping and see if it improves the flow. It's a light tap I use anyway as I noticed a heavy tap disrupted my nice lightly-tamped puck. But the tap I was doing was not after my final tamp, it was to settle the newly ground pile into the filter. Then I tamp it.

                            I've seen (but never done) some coffee makers bang their PF solidly on the bench - maybe they don't have my miserliness about watching my hard earned coffee grounds spray across the bench.

                            The finger tap I mention is just a gentle tapping on the side to get the dome to even out after grinding, then a light tap on the mat and tamp it.

                            Something I've wondered about; should I polish after each tamp? I've been tending not to because I thought it might create planar surfaces deep in the puck rather than allowing a smooth transition between tamped amounts. I learned the no-pressure-polish thing very early on when I noticed the difficulty I was having keeping my coffee level if I spun the tamper while under pressure. It was much easier to tamp level then spin the tamp than try to keep a rotating tamper level.

                            Interesting read on tamping. Mind you, his one about the God Shot was pretty informative - must go make a coffee...
                            Hi Journeyman

                            Even a fairly light tap can sometimes result in uneven streaming. Although it is not really channelling, it is still using extra effort to create an unwanted problem. On seriously busy days, every movement counts...

                            When you go naked, it is surprising to see the sheer volume of the horde of gremlins coming out of the woodpile. Ditto VST's. I literally had to go back to first principles again to get rid of ingrained errors that crept in over the years. I still marvel at the difference it made on my La Pav. Always a good ego trimmer to do something on a machine that you think you have tamed over a decade ago and be astounded!

                            Polishing: I have even seen strong disagreement on CS posts about this. I believe one key issue is as you say "It was much easier to tamp level then spin the tamp than try to keep a rotating tamper level". My tentative conclusion: When using progressive tamping if you polish a puck off properly it is always a slightly different pour than no polishing. I suspect it makes a +ve change to the taste, however we all know 'bout the power of delusions*. Consistency rules supreme: so either polish it properly using no pressure "in the spin", or do not bother to polish at all and adjust the grind or dose slightly instead. I remain convinced that "tearing the top of the puck" is always bad news (it channels), and that is as far as I will commit.

                            *FYI, I read somewhere (buried in an old mag I kept for other reasons) that an Italian barista at one of the championship comps did not tamp at all. Although he did not win, it also made me go back and try the "no tamping technique" about a year ago. Unsurprisingly it needed a complete revision of grinding & dosing to get a good result. At the end of the day I gave it up more due to (my?) lack of consistency than giving the method the thumbs down. Using a naked it tended to stream and spray. When it decided to behave, it gave a truly excellent cuppa. I often wonder if it meant that it would work if you were willing to count the individual granules, pray to the correct deity or whatever... for him to compete at that level it must have been possible somehow.

                            God shot: When a guy with enough talent gets his hands on a decent grinder** and a 6910, it is amazing what con be achieved.

                            ** I heard several times it was an EM480. Given my experience with them, when correctly set up they are "up there" in my view. That is why I bought my 480/6910 for home originally - one stale grind retention too many and a warmup taking too many frustrating eons from my commercial "home" setup when all I wanted was a single decent coffee in the same calendar year. Oh, and all that without the need to spend 30 minutes and 4 cups in an arcane Byzantine ritual first... I literally took a punt and have not ever regretted the purchase for home use.

                            Have fun

                            TampIt

                            Comment


                            • #29
                              Originally posted by Darkfalz View Post
                              My pre-tamp is just for distribution, it applies no pressure, just the weight of the tamp.
                              Ah... that's the reason I tap the side of the PF with my fingers. It's not so bad with my EM0450 grinder as that hasn't got the PF holder or the rubber spout so I have more scope to move the handle around as I grind and so get reasonable distribution. But the 450 is set for the wife's decaf. The 480 tends to spray my preferred beans around a bit so I leave the rubber on but I am thinking of removing the PF holder.

                              Even so, on both of them, I tap sideways to even out the mound; my thinking is tamping on a mound will compress the centre much more than the sides. So I am unlikely to not tap by finger. I'm trying the no-bang (using 'bang' to differentiate from my tapping) PF method mainly because, as TampIt says, less movements = more efficient - for similar reason I have also moved towards doing only 3 steps in the progressive tamping. I haven't noticed any difference in reducing it from 4 steps and I did side-by-side shots to test it. (well one shot then another... )

                              I will say this though (i.e. getting back OT) with the changes made to my technique across the past few months, as well as getting a naked PF and VST baskets, my coffee is much better than it was and I have been unable to get a coffee that pours anywhere near normal and has the bitter taste of a macchiato from most cafés - I actually asked on CS about it but so far the suggestions I have tried tend to give shitty pours - if it pours OK it tastes good - and the café versions pour OK but have that taste.

                              Maybe I should leave some beans out in the open for a couple of weeks?

                              Comment


                              • #30
                                Originally posted by Journeyman View Post
                                The 480 tends to spray my preferred beans around a bit so I leave the rubber on but I am thinking of removing the PF holder.

                                Even so, on both of them, I tap sideways to even out the mound; my thinking is tamping on a mound will compress the centre much more than the sides. So I am unlikely to not tap by finger. I'm trying the no-bang (using 'bang' to differentiate from my tapping) PF method mainly because, as TampIt says, less movements = more efficient - for similar reason I have also moved towards doing only 3 steps in the progressive tamping. I haven't noticed any difference in reducing it from 4 steps and I did side-by-side shots to test it. (well one shot then another... )

                                I will say this though (i.e. getting back OT) with the changes made to my technique across the past few months, as well as getting a naked PF and VST baskets, my coffee is much better than it was and I have been unable to get a coffee that pours anywhere near normal and has the bitter taste of a macchiato from most cafés - I actually asked on CS about it but so far the suggestions I have tried tend to give shitty pours - if it pours OK it tastes good - and the café versions pour OK but have that taste.

                                Maybe I should leave some beans out in the open for a couple of weeks?
                                Hi again Journeyman

                                480: Mine does not use the extra silicone / rubber thingy, it does use the 58mm p/f holder. It does not throw much (I could leave the bench uncleaned for 4 or 5 shots and not have to worry about domestics), however I have now noticed that I hold the p/f quite "high" on the auto switch. Also, as discussed, I clean it out with my compressor every 250 to 500 grams so the mechanism does not build up crud.

                                4 to 3 steps: it actually does make a very subtle difference to the pour, which is easy to adjust via grind / dosing anyway. FWIW, the only time I do the "whole progressive thing" is when I am dialling in a new roast or machine. I then know exactly what I am trying to alter until I get at very close, then I do fine tuning with whatever method I have chosen. When learning, the full version helps consistency especially whilst you learn how to tamp level with an even pressure... Knowing what and when to compromise plus exactly the effect it has is, IMHO, always a good thing.

                                Prepare yourself for a rant, or skip 2) until 6). "bitter taste of a macchiato from most cafés":-
                                1) I have mentioned grind retention several times. Ground beans oxidise in 15 minutes at normal temp & humidity (whatever that means). Even if everything else is perfect, less than 2g of oxidised grinds destroys a (say) 15g double by going bitter and often tasting stale to boot. Most commercial grinders retain 2 to 5g, whilst certain (well regarded) doser models easily double that. They really do waste a lot of coffee if you run it long enough to get rid of the oxidised stuff (most places don't). I still regard it as the elephant in the room for baristas, given it is generally ignored.

                                2) The same grinders also usually use the weight of the beans to feed into the grinder (as does your 480 /450 and almost every other domestic burr grinder). Those that clean everything out and measure the exact quantity of beans (whether by weight or volume) into the hopper lose out due to the feeder mechanism messing up the particle size consistency as the weight of beans drops. The extra airflow would be relevant if the beans are preloaded, however that is rarely seen. Those that keep the hopper full win that battle, but lose out because beans hate light, heat, moisture / humidity and airflow and they have increased the potential exposure to all of them. FWIW, I have a "medical grade neoprene / rubber" plus metal weight in my 480 which fits exactly near the bottom of the hopper, and is tapered to match the hopper's curve. Until the beans get to the "sharp curve" it is always over 250g loading into the mechanism. First 480 mod I did in 2010. Apart from massively reducing the airflow, it also stops the beans from bouncing around as a free bonus.

                                3) Some grinders overheat the beans as they grind, whilst the big motors on other ones transfer significant heat into the beans via the grinder housing after a few shots. The housing is often a conducting metal which really enables the process... And so many CS'rs slam plastic housings?

                                4) The cafe environment often has the grinder too close to the espresso machine or other hot spots, which also helps to kill the beans off.

                                5) As mentioned above, humidity is a killer as well. One of my other pet snafu's is to watch clouds of steam hit just below or on the hopper. I love it when the condensation runs down the side of the hopper into (somewhere)... Never helps, probably hurts. Fastest way I know to render a Robur's grind useless until the next major clean (seen it at two different Melbourne cafes that really should have known better).

                                6) If you let grounds go into the grinder mechanism (normal use does a little of that), it throws the particle consistency out. The number of times I am asked to dial in a troublesome machine when their grinder is actually unable to work properly until a top to tail cleanout is performed... I believe it was you that said something about “as clean as a hobo in a tip” or suchlike? I have lived it too often. Not to pick on a Robur (I kinda like them) but their users seem to regard them as indestructible. That may be true, however if you want decent coffee out of them surely they deserve a little attention? I have actually taken them to a nearby servo to blow out the worst of the gunk before hitting them with one of those “almost useless” compressed air spray cans to remove the extra moisture a servo air gun often provides free of charge.

                                7) Most catering blends are rubbish.

                                ... are you still wondering why their macc's are bitter?

                                Cheers

                                TampIt

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