I’m finding it difficult to understand why the two differ in their flavour outputs. If I’m not wrong, both increase extraction?

I have been playing around with an older coffee (roasted mid Nov 22);

  • 14g in, 30.8g out, 31 seconds (was aiming for a 1 : 2.3 ratio)- awful tasting, astringent finish, no specific notes, just not a nice coffee
  • 14g in, 41.7g out, 27 seconds (was aiming for a 1 : 3 ratio) - much nicer, lovely sweetness, way more balanced, specific notes were present, actually enjoyable

I think going a touch coarser may even improve it more. I started off somewhere in between those 2 results, and started to grind finer first. When I got a horrible result I went the other way and it transformed the coffee. Sometimes coffee gives great results sticking to the “typical” parameters, sometimes not.

Can someone please explain to me like I’m five, what the difference is between grinding finer, and increasing yield? And is there any way to gauge how a coffee will give the best results?

At too short a ratio, grinding ever finer can reach a ceiling, then because water can’t permeate the puck, extraction drops if you go finer still, then your coffee will be both sour & bitter - sour from under-extraction and bitter because it’s full of silt.

At a given grind setting, increasing extraction (to a point) is more easily done by passing more water through the puck…there is a trade off though, longer brew ratios ultimately make a weaker drink. There won’t be any overlap in strength between a 1:2 shot and a 1:3 shot at typical extraction levels.

There isn’t anything particularly atypical about a 1:3 shot. I have pulled many, many shots between 1:4 and 1:6, ratio is more linked to flavour balance vs coffee solubility. So a darker more Italian style coffee I may pull more like 1:2 to 1:3. A light roasted, or less soluble bean I might pull `longer.

It can be easier to detect separate flavours in a more diluted shot.

For less soluble coffees it can actually be very hard to over-extract, even at 1:5, though siltier cups might be less`tasty & flat, long before over-extraction happens. (Extraction is based on solubles dissolved in the coffee, solids are not dissolved but can still have an adverse effect on flavour if in too high a proportion).

In short, I play with ratio a lot, but my grind adjustments are relatively small.

So if we stick with the coffee I was using (for ease of my understanding) - using my grinder there was a 1.5 notch difference (I have no idea what that translates to, but I have no other way to convey to you how much/little I changed the grind setting) in the SPTK38. Given I had to change grind setting to get that second output which gave me a tastier shot, if I had not changed grind setting but still aimed for 1:3 it would have taken perhaps 40 seconds? Would that shot have tasted the same as the one where I did change grind settings and used a 1:3 ratio?

  • MWJB replied to this.

    DrForinor I don’t really pay too much attention to shot time, if it took 40s and tasted OK, I wouldn’t sweat it. If it didn’t taste OK, I’d go coarser.

    I don’t really expect shots at different grinds to taste the same (maybe characteristic of the coffee still, just differences in brightness vs drier & more mouthfeel), because what you percieve is a mix of both dissolved & undissolved coffee, so maybe the extraction would only be a bit different, but if you were too fine, the flavour would be maybe flat, less balanced

      There is a barista hustle that goes through tuning a bean and explains what can happen. A free one

      Different beans will need different tuning. Rules? Not any really. LOL I posted this elsewhere due to 1 to 2 in 30sec merchants but the web is so firm on that probably wasting my time. People seem more interested in that than how the coffee tastes. Pallets vary as well.

      As the video says a refractometer is not needed really. It’s all about taste not set numbers.

      It’s possible to get an idea of tuning at the commercial end for free. In short they are interesting in cost per shot and probably time too. Maximise yield figures but that will need a blend that suites. Shot time. I have noticed sone that are rather short.

      New beans and new machine. I obtained an awful taste and smell. I was using 14g which meant expansion was being limited reducing flow rates. Over filled basket. Stupid of me really. Cut back to 12.5g and bad aspects gone. A ratio of a bit over 3 gives a strong flat taste. When I cut back to ~2,5 I expect a bite to be added while drinking it, one that fades which is what the bean should provide. Some prefer this bean with less water flowing through - reducing shot time not grind,

      I’m still confused, if I’m honest.

      How do I know taste wise where I have went wrong, in relation to grind vs yield? Meaning, if it tastes bitter, how do I know if I have went too fine, or my ratio is too high?

        DrForinor So 1:3 with this coffee, at 1.5 notches coarser than the less pleasant 1:2 shot, worked well.

        Do you feel that you need to adjust anything, given the shot was as you described?

        I wouldn’t adjust anything with this coffee, until a few shots in succession show the same fault.

        If the next coffee/successive brews with this coffee start becoming sharp/tart, try a slightly finer grind. If you can’t shake the sharpness/tartness with grind adjustment, or the shot is very sharp/tart go longer on the ratio.

        If shots with another coffee are flat/silty/muddled in flavour without sharpness/tartness, shorten the ratio, if this doesn’t fix it, grind coarser. If shots taste balanced at long ratios, but are just too weak & lacking intensity, try a shorter ratio and grind finer if tartness/sharpness creep in.

        Bitterness can be inherent in coffee, some coffees just have more than others, without knowing the coffee itself it’s hard to advise. So look for other defects as well as the bitterness (chalky/powdery mouthfeel, lack of acidity). Over-extraction is a very specific bitterness, very drying and smoky, dominating the flavour. It is often very difficult to do in espresso at 1:2 or 1:3 even if you tried hard. I don’t think advice to adjust based on bitterness (in general) alone is very useful.

        I find sharpness/tartness a better indicator (as opposed to pleasing, fruit like acidity bearing in mind some fruit are sour - it’s that puckering sourness we want to avoid) as this is pretty much always under-extraction. Also if the shot is so intense that it is preventing you from determining quite how it tastes, go longer.

            MWJB Ok that helped a great deal there, know what to look for taste wise and how to adjust. Thank you!!!!

            When I say bitterness, I’m getting a dry astringent finish. If I get this, do I go shorter with the ratio, or keep ratio same and grind coarser?

            • MWJB replied to this.

                Another query, as a coffee ages - as a general rule - to get a better result from it what seems to work better with grind/ratio? Finer/coarser? Longer/shorter? Or is there no general rule, and go purely on taste?

                • MWJB replied to this.

                  DrForinor When I say bitterness, I’m getting a dry astringent finish. If I get this, do I go shorter with the ratio, or keep ratio same and grind coarser?

                  If the intensity of strength of the shot is acceptable, I’d grind coarser in the first instance.

                      MWJB If the intensity of strength of the shot is acceptable, I’d grind coarser in the first instance.

                      If I’m getting the same finish (dry), very little sweetness, very little of the indicated notes, still stick with that same protocol?

                        DrForinor Another query, as a coffee ages - as a general rule - to get a better result from it what seems to work better with grind/ratio? Finer/coarser? Longer/shorter? Or is there no general rule, and go purely on taste?

                        I don’t tend to buy big bags, nor make lots of brews from one bag via the same method, but if we are talking about the same coffee, that is displaying the same fault in more than one successive cup, change the grind.

                        For a little context, if you are enjoying a coffee brewed to 18% extraction at 1:2 the concentration of the shot would be around 9%TDS. But a high 22% extraction at 1:3 would be around 7% TDS. So at these intervals in ratio there is no overlap in concentration and therefore, if the strength intensity is OK and you just need to adjust flavour balance, use grind.

                          DrForinor Grinding finer/coarser affects extraction as does changing yield. Yield also changes dilution. Bear in mind that you can be grinding too fine and know what this tastes like, as described above. Don’t worry too much about shot time but pay attention if shots are very slow and quickly speed up, and other signs the puck is fracturing like obvious channeling. Also, look out for like excessive sediment in the cup and lots of clogged basket holes, there may be other things too like lots of ‘oil’ on the basket after the shot but not so sure about that….eventually you’ll know the grinder and know when you’re going to be pushing it. You may find that with some coffee you have to increase yield to get a good extraction which is probably what has happened in your example - presumably, you tried simply grinding coarser at the lower ratio with less than pleasant results?

                              Rob1 I think I don’t give “grind coarser” enough credit - that’s probably my issue. My head sits (obviously wrongly) in the space where I’m thinking, finer grinds means more extraction means better tasting 🤦🏽‍♂️🤦🏽‍♂️

                                MWJB I don’t think advice to adjust based on bitterness (in general) alone is very useful.

                                This bitterness is with Union Roasted Bobolink, which I have experienced nice sweetness with before, nuttiness, chocolatey as well.

                                • MWJB replied to this.

                                    DrForinor If you know the sweetness to be in the coffee, and there’s no sharpness/tartnness, then I’d be adjusting coarser.

                                      I’ve started (last couple of days) tapping towards the bottom of the portafilter to level the grounds. Before this I used to tap towards the top of the rim to level it. Since this change (I’ve changed nothing else) the coffee has really thrown me (2 coffees).

                                      Can that change really affect it that much?

                                      I do a downwards tap, then a couple of side taps with the heel of the hand to level.

                                      In what way has it ‘thrown’ you?

                                      With the taps at the top of the rim, I was around a certain grind setting (not really having to change much, perhaps half a notch either way) for most coffees. Now that I tap towards the bottom, I’m having to go at least 2 notches coarser.

                                      • MWJB replied to this.