LMSC cool. That means I just not familiar with the relatively light roast beading only.

Hm… honestly I am not good at describing taste. But I think it lean more toward to the medicine like bitterness and the after taste bitterness leaves there long. Compared to the expresso I had in cafe (where I prefer slightly more bitterness than sourness), it is different but not hugely different by nature. But the bitterness in my shot Is definitively striking and not pleasant. Sorry I cannot describe it better. But I appreciate your help.

If my beading is okay, I will then move to coarser to try until the shot got problem such as very watery and extremely short brew time. And at that time if I still have this Brazil beans left, I will go another direction to try something coarser than the start point, ie 1.7.0. Make sense?

      Knluk I would try pulling this grind setting again but with less preinfusion time, see how that tastes. If it’s still bitter try lowering temp by a degree or two (temp may also be worth adding to your chart too to keep track of).

      I also recommend you up the dose from 15g to 16 or 17g of coffee. The Robot is capable of doing doses as small as 12-14g but I’ve always found those harder to get the most out of. It’s far more forgiving with larger doses which I imagine is down to the depth of the basket.

          FadedFrontiers sure thing. Do as instructed :)

          1. The first shot was similar to yesterday’s. Temp was reduced from 95c to 93c and increase dosage from 15g to 16g. Also, preinfusion was shortened to 5s.
          2. The second shot - I further increase dosage to 18g. This showed observable improvement. Still bitter but less striking and less long lasting. But LMSC i paid attention to it. Yes- I am pretty sure that it is me medicine like bitterness. But this shot is marginally drinkable. I don’t enjoy it much. But I will drink it when I crave for coffee. Also, notice some floral smell and after taste. But lack of sweetness.
          3. Third shot - I kept everything the same but with some confidence built up(?) I decided to coarse up the grinder by one click and pretty confident that it will show slightly improvement. But it returned to the level of yesterdays. Pretty frustrating for this :( Below is the video of the last shot.

          With my fast speed wasting bean (but I appreciate all the learning), I will use up my Brazil bean in a day or two. Plan to stick to the best shot today and try to pull a shorter shot. My thinking is to get rid of the last part of the shot which is bitter. Does it make sense to all fellow members here?

                Knluk My thinking is to get rid of the last part of the shot which is bitter. Does it make sense to all fellow members here?

                You are free to do whatever works for you, but no, discarding the last part of the shot makes no sense. Just pull a shorter shot if that is what want.

                In a balanced shot, even if the last part of the output is weaker & bitter, the shot will still be good, because the early part will be under-extracted & sour, even if you kill the shot when the last drops taste good on their own (this is something I have explored in the past - discarding 1st drips, discarding last part).

                Why not just make 3 more shots at 1.7.3, 18.2gin, 37.1g out and ensure that they are consistent?

                I’m a bit confused by your scoring and analysis, you are scoring out of 10, so 5.5 would be neutral, neither like nor dislike, 6.5 would then be a positive score in that it was likeable, but you have had better & know there is room for improvement, yet you say, “But this shot is marginally drinkable. I don’t enjoy it much”? 6.5 might be a score I’d give to representative shot of mass market espresso blend, where I’d be perfectly happy with it in context and I wouldn’t ever expect a 9 from it.

                The scores of 5.4 to 5.6 are all essentially the same thing, differences of +/-2%, which are inseparable from noise. Try and simplify the scoring & make a call to keep to whole digits, or 0.5 intervals.

                    MWJB yeah see how consistent the shots are at the same setting for the next few attempts. Different tamping pressures could cause different results for example, you could always try to record the pressure you tamp with.

                    My next step is a counterintuitive based on the bitterness but I’d actually grind a little finer and see how that affects the taste (try one click at a time). I say that because the higher dose at the same grind (which resulted in higher pressure) was the best shot so far.

                        Knluk your beans are super dark roasted judging by the pic - they look almost black and oily, I think the bitterness you describe is not fixable for these beans. I suggest getting a medium roast - these in my experience respond better and more predictible at changes in recipe.

                            MWJB thank you! Always appreciate all the useful suggestions. And I shall try three more shots for the best shots.

                            Re the scoring, i was using a school examination, 60% pass score, and maybe 80% very good and 90%+ excellent. I have to admit that I think about it systematically in the first place 😂

                              90% coffees (in terms of cupping potential) are extremely rare.

                              My brews average about 84% a mix mostly of 7 & 8’s (out of nine).

                                Petre the thread May be confusing.

                                I am now using this beans which I think is medium dark roasted. see pic below.

                                Below is the last bag of beans I used:

                                    MWJB what is your score for drinkable?

                                    I may have a different scale. If I drink a nice coffee from a random speciality cafe, I give it a 8.5 or 9.0.

                                    • MWJB replied to this.

                                        Knluk oh alright then, the first ones look more like medium indeed.

                                          Knluk when you’re ready to tamp, just put the filled basket on top of a bathroom scale and see what sort of pressure you register as you push down normally with the tamper. 20-30lb of pressure is always mentioned for standard espresso machines but it shouldn’t matter too much provided you’re consistent (I’ve found a light fingertip tamp to be fine for the robot, just try to keep it the same each time and most importantly keep the level with the tamper handle in the middle as much as possible).

                                          I only suggested it because I imagined you’d been using a bathroom scale for measuring the pressure with the robot arms, it shouldn’t be a huge factor but just something to keep in mind.

                                            Knluk what is your score for drinkable?

                                            I may have a different scale. If I drink a nice coffee from a random speciality cafe, I give it a 8.5 or 9.0.

                                            I don’t really understand the question, if you don’t drink it, you can’t score it. I drink what what I make (if can).

                                            Here is the scale I (and sensory testing) use:
                                            1 = Dislike extremely; 2 = Dislike a lot; 3 = Dislike moderately; 4 = Dislike a little; 5 = Neither like nor dislike; 6 = Like a little; 7 = Like moderately; 8 = Like a lot; 9 = Like extremely.

                                            85-90% as a rule, seems unrealistic to me.

                                                Tamping pressure to an extent doesn’t matter, as long as it’s level and consistent.

                                                Looking at the vids you seem to have quite the pre infusion going, personally I prefer a shorter pre infusion. 5-6seconds for drips.

                                                The coffees you seem to use will have a bitter note, that’s what they are roasted like. I know choc point can have a bitter dark chocolate note.

                                                Perhaps you need something more medium?

                                                It’s easy to get lost when doing what you’re doing.

                                                I’d say find a grind settings, stick with it then alter ratio. Have you pulled a 1:1 ristretto?

                                                Don’t go off looks, let taste guide you.

                                                I can recommend north star brazil for a good med roast. That’s traditional flavours

                                                Decent De1pro v1.45 - Niche Duo - Niche Zero - Decent is the best machine ever made -

                                                  Cuprajake thanks for the suggestion. 1:1 seems interesting to try. The beans I am using is actually the NS Brazil : P

                                                    MWJB make a lot of sense. Will try to use similar rating definition for ease of understanding.

                                                      Cuprajake The coffees you seem to use will have a bitter note, that’s what they are roasted like. I know choc point can have a bitter dark chocolate note.

                                                      Yeah! That’s why I asked him. Knluk says they are medicine bitter, although I still think what’s described as bitterness is either chocolate note or the roast. Personally, I would expect both the beans to have some bitter after taste. Based on the picture one is at least a medium dark and another is dark for me.

                                                        Good day all! I finally made it! Appreciate all the help I got here.

                                                        I pulled two more shots (finer grind and 1:1) on the Brazil beans yesterday, which are not worth reporting. And the beans are used up.

                                                        I started the chocolate blend today and like it a lot at the first shot! Thanks @“LMSC” for the recommendation!

                                                        I am suprised that all the parameters, ie pressure, brew time, are spot on. The flow in the naked PF is advertisement type (although not the priority). I am already very happy with the taste but I think of pull a few more shots to see if any improvement. The taste is very balanced. Although I like thicker texture, I still think this shot is a tiny bit too thick. Maybe I can try 1:2.25 ratio?

                                                        Also, I found that quite a bit of the ground is trapped at the blurr compared to my previous beams. Does this happen to you?

                                                          Knluk It doesn’t matter if a few grinds stick to the burrs, you’re weighing the grinds out anyway.