Knluk - Go to the supermarket and buy yourself a tin of the world famous Illy coffee - that might be something you would be more used to, specially if the automatic machine is giving you good coffee. You didn’t say what coffee that machine has though, but I’m assuming if it’s something in an office with an office plan, it’s likely to be something very box standard.

And then try something medium/medium dark roasts from roasters - keep it to a well tried blend.

Are you sure you are detecting bitterness rather than sourness? With the Robot, the temperature is always decreasing - there’s no way to increase it. Usually, bitterness is a sign of the water being too hot - which I very much doubt with the machine you have.

Needless to say, this is a journey. If you are a a novice to this, you there will be a period where things will be frustrating for you, specially with the kit you have, due to its limitations.

Also, don’t get carried away by the nth level of detail. Grind your coffee, tamp, pull a shot. Keep things consistent. Change one variable at a time. Keep to the simplest possible routine you can have. When you introduce a change, think about what it represented in the cup. Go again.

      Knluk my jX-pro is really the cause

      Your grinder is fine. It is a lovely grinder, which is what I have and use daily for espresso and pour overs.

      You said, you have two shots:

      1: Your latest video is good. I can see why you are saying it is channelling. Keep everything constant, coarse grind by another 4 micro clicks, pull a shot and see what happens. A click or two in JX pro may not make a difference to the shot. I doubt I can tell the difference in taste.

      1. Since it is a dark roast, pull a shot with 1:1.5 and see if you like.

      As advised by folks here, get Illy and get another a medium roast bag and see how it goes. If you have a roaster nearby, go to them, see if you can find a medium roast bag roasted 2 -3 weeks ago and use it.

      Worst case, if you are out of coffee, go to Waitrose and get an expensive small coffee bag (not powder) you can find and get that if and only if there is a roast date (not best before). The waitrose bags will normally have a roast date. Do not the buy if the roast date is more than a month. If I am out of coffee beans, I won’t drink coffee. Period! 😊

      BTW, what are the flavour mentioned on the bag? Since, it is a dark roast, you may find Cocoa, (dark) chocolate and nuts.

          MediumRoastSteam thanks for input! Below is a pic of the automatic machine. I like the shot but I do prefer the other shot I had in a specialised cafe. For Illy, are you referring to beans or ground? Do they normally have a brew date? I bought a bag from sainsbury branded Union with brew day slightly over a month old. I don’t want to touch that after two shots :(

          I think I am tasting the bitterness as I feel it more at the back of my tongue

          Re changing one variable, should I change grind or ratio based on my current problem?

              LMSC great input for the grind setting on JX pro. I gonna try that. But one question. My pull time is currently 27s. If I were to increase ratio to 1:1.5 and coarsen the grind but maintaining same pressure, I will likely finish the shot at 15s. Won’t it be falling outside the sweet spot of 25s to 30s? I hope you can see how I am stuck with all these variables. Not to mention that I feel very confused reading about an article on how the taste change with pressure/ ratio/ temp/ extract time/ grind size 🤷‍♂️ I will try your suggestion anyway

              Below is the bean I am using for ref on the taste note.

                  Knluk For Illy, are you referring to beans or ground?

                  Ground coffee and espresso don’t get on well, at all. For espresso (and if you want good coffee) always grind on demand.

                      Knluk Your total shot time includes the PI. As MWJB said, don’t worry too much about the timing. There isn’t anything like a universal sweet spot timing. Let it take as long as it should, provided you like the shot. Similarly, your taste should dictate the ratio. I know one Evo Leva owner, who always drinks a dark roast, pulls 1:2 and takes 45s-50s for the shot to complete. This gentleman’s timer starts only when a drop falls into the cup. 😊

                        Knluk For Illy, are you referring to beans or ground? Do they normally have a brew date?

                        Illy tins have two dates: a ‘Best Before End’ date, with month and year, and a ‘packaged’ (ICS) date with a day, month and year (and time of day).

                        The ‘BBE’ date is useless, but the ‘packaged’ date gives you a good idea of when the beans were roasted; if (unlikely) it’s recent, then a few weeks of useful life can be inferred (say 6-8 weeks from packaging date*); if it’s months old, the coffee will be fine when just opened, but will deteriorate in the space of a few days.

                        * You’ll read all sorts of dates for shelf life of roasted coffee, ranging from 2-3 weeks to 6-9 months from roasting. This is one of those areas where you need to make your own personal opinion up on what “still tastes good” to you, and that may very well vary by beans and brewing method. The 6-8 weeks is when I find that Illy beans (which I use often) start tasting mostly of burnt wood, rather than nice coffee; I’m well known for not having a particularly discriminating nose or palate…

                            Knluk You are over whelmed with information overload. Please take it easy. Why don’t you step away from the machine and try again when you are fresh? 😊

                            MediumRoastSteam CoyoteOldMan

                            If a bag is just a little over a month old, it should be still good and should not be like “don’t want to touch it….”. I am also thinking a milk chocolate as a flavour not necessarily not generate a little bit of chocolate bitter taste. The best example I can give is the Docks blend (milk chocolate, toasted nuts,…). The roaster’s description is bitter sweet chocolate. if one were to drink as a black than with milk. That’s what I get as tasting notes in my coffee.

                                    CoyoteOldMan been to Waitrose and also checked our M&S food just now. As you expected, the package date was Mar 2022(!). Will try to buy some beans from a local speciality cafe tomorrow although they don’t have brew date shown. But the owner said for the beans on shelve, average age was 12 days after brew.

                                      Knluk I hope you can see how I am stuck with all these variables.

                                      There are 2 variables, grind setting and brew ratio. Do everything else the same & remember making coffee takes time, but the time it takes is not critical to the result, so record the time as a vague frame of reference, but don’t give it unnecessary importance.

                                      Remember those scores, bitter & sour are only so useful…especially considering coffee is often both at the same time.

                                      I don’t see anythig wrong with buying a small tin of Illy preground for espresso to try as a sanity check. It won’t last long, but maybe enough to provide a clue.

                                      Also see if you can find out how much coffee the Franke machine doses, see what the brew ratio is.

                                        LMSC very true. I think about it all the time and try to sort out what went wrong. Will try to take a break. But I still can pull two shots from the remaining beans. Tempting :)

                                        • LMSC replied to this.

                                            Planned to do a better job in managing the supply chain of beans given they need to be store at least two weeks before consuming. I searched about the contents here about storage, but seem there is not consensus on whether freeze it or not. May I check whether I should freeze it or just use the original zip bag come with the beans for storage. I saw people using vacuum seal bag, is it only for long term storage? I will aim at store it for 14 days without opening the bag and consume within the next 14-21 days. Thanks.

                                            • MWJB replied to this.

                                              Knluk How many coffees are you going to make per day?

                                              A 250g bag holds 14× 18g doses max, so 2 weeks even if you make 1 shot per day.

                                              If resting 2 weeks, brewing in the next 2 weeks, it will be fine to leave the beans in the resealable bag.

                                              The consensus for 70yrs has been that freezing preserves coffee. But if freezing, freeze in small, rested, batches/doses that you will use straight away (hence vacuum sealing in portions).

                                                  I had a Robot and all the best advice on using it comes from the inventor on the Cafelat YouTube channel, you can see how he preps and pulls shots. Hoffman does mention his technique in the review but I’d stick with the guy who invented it to start with before experimenting.

                                                  I wouldn’t get too obsessed with bean storage and hitting some mythical sweet spot window when they aren’t too fresh or too old, to start it’s about grind size and technique on this machine. There is no need to pre-heat either according to Cafelat, people may disagree with this in general but I’d listen to people who have the machine and use it to pull shots, rather than general coffee theory.

                                                  After you’ve got that down then you can start obsessing over the smaller details.

                                                    MWJB I drinks 2-3 shots a day, currently using 18g per shot. Good to know I can keep it in the bag for short term. I prefer not to go too complicated for storage and focus on coffee making skill first. Thanks!

                                                      gotters is this the clip you referred to?

                                                      I watched that before and rewatched it just now. What I did differently was:

                                                      • I feel 5mm to full instead of 1cm
                                                      • I used 18g instead the 14g he mentioned.
                                                      • I am not sure how much liquid he extracted but that look like he is using a much lower ratio than the 1:2 i normally used. I was told to try longer shot. I tried 1.25 yesterday but it was bitter. I think that’s sign I either over extracted the coffee and/ or the shot it too long so I captured too much of the later liquid which is bitter(?)

                                                      Would love to hear your recipe in term of ratio and gram of coffee.

                                                      great advice on the storage. I feel very relieved.

                                                        I took the advice from above. Went back a cafe that served me the espresso I really like and bought the exact beans he used. I enquired about the lack of roast day and he said once the beans were roasted, they were rest and packed with gas inside an expensive valve bag. So as long as it is not open, it can be kept for months without problem. I know it is contradict to the opinions of almost all home espresso enthusiasts here. But the North Star and black cat beans I have are all too fresh, why not give it a try. At the end of day, the barista used this to produce something I like.


                                                        From appearance, the beans are dark and oily. Smell pretty nice (this is useless comment though as I like the smell of any coffee). I applied the knowledge I recently learnt and here was my plan for the first trial dial in:

                                                        • it is pretty dark. And I tried 1:2.5 in my old bean yesterday and it was overly bitter. So to avoid I capture too much of the bitter shot in the last part, I reduced ratio to 1:1.9.
                                                        • It is pretty dark. So I worried about over extraction, so I sit the boiling water in the kettle for 20s before pouring. And I changed my grinder setting by 2 dot coarse

                                                        Here are what the resultant drink:

                                                        • pretty thick body
                                                        • Very dark in colour
                                                        • Drinkable but nothing close to good. Less bitter than my last shot with 1:2.5 ratio. But the bitterness is still pretty striking.
                                                        • I made a latte with it. The bitterness and burnt taste still quite profound.

                                                        Grateful if I can have some advice on the next trial dial in? I am thinking keep everything the same but go coarser? Maybe further increase the ratio to 1:1.8?

                                                          Knluk It is very, very unikely that you are over-extracting, so don’t worry about it. You’re not measuring it anyway, so tell us how much you like/dislike, rather than second guessing unusual faults that you can’t diagnose.

                                                          It is much more likely that you are under-extracting.

                                                          Bitter happens for many reasons, not just one. Over-extraction is an intensely drying, smoke like bitterness, you’ll know when you get it. The result will not be drinkable.

                                                          You’re going round in circles if you go shorter, you’ll be grinding finer, making more bittering silt & the coffee will be so intense you won’t be making sense of it. Eventually you go too fine & extraction drops again.

                                                          Coffee is bitter, coffee is sour, it is often bitter & sour at the same time. It was roasted & is often charred/burnt…none of these things is helping us troubleshoot. Give us a numerical score, grind setting & ratio so we can see how they relate. Every bag of coffee tastes different but the dial in process is the same and the same things apply to all of them.

                                                          I’d go 1:3 and coarser until the coffee starts becoming too weak and tart/sharp, then tighten up the grind to where it tasted best. If you need more concentration, then look to shorten the ratio.

                                                              MWJB Yes. You could see my feeling. I really feel like circle. I was at 2.1.0 (on the coarse side) setting before. And tried to go fine to 1.4.2 where I choked the Robot. The I slowly step by step open the grinder to 2.1.0.

                                                              Do you mean I should report back something like this:

                                                              • grind 2.1.0, 1:1.9, score 3/10
                                                              • Grind 2.0.0, 1:3, score 5/10 (this row is make up number)

                                                              Really appreciate your advice. Cos I really directionless on which side of the spectrum in grinding or ratio I should heading to.

                                                              • MWJB replied to this.