What you taste, what to change and why, from the dial-in advice of Lance Hedrick, James Hoffmann, Daddy Got Coffee, Kyle Rowsell, The Coffee Chronicler, Sprometheus, European Coffee Trip, Brian Quan and Bluebird Coffee Roastery (the By column says whose). The Tag column matches each symptom to Notchbook's taste tags (sour, balanced, bitter, astringent), and other means the problem is about flow, texture or the grinder rather than taste. The same rows are in data/dial-in-guide.json under troubleshooting.
How to read a tag
- Sour (sharp, salty, thin, lacking sweetness) usually means under-extracted. Push the extraction with a longer ratio first, then a finer grind, more contact or more heat 25:33 4:04 16:28.
- Bitter (harsh, muted, often with a dry edge) usually means over-extracted, so shorten the ratio, cool the water or go coarser 24:02. Bitter and sour at the same time, or bitterness on a fast shot, often means channelling from grinding too fine. In that case go coarser and fix the puck prep instead of pulling the extraction back 22:52 6:13 2:31.
- Astringent is a physical drying or puckering, like strong tea or a green banana. It's a feeling rather than a taste, and it's often mistaken for bitterness. It usually comes from too much extraction, especially on light roasts, so extract less. On dark roasts it's more likely to be bitterness, so cool the water. See Astringency 1:55 15:41 15:37.
- Balanced means leave the grinder alone and pin the setting. A little bitterness can round out a bright cup, and the right balance depends on your palate 14:19.
Change one variable at a time and note what you changed 20:01.
Espresso
| Symptom | Tag | Change | Why | By |
|---|---|---|---|---|
| Sour, salty, thin | sour | Extend the ratio (e.g. 1:2 to 1:2.25, or 20 g in and 45 to 50 g out), then grind finer or lengthen the contact time 25:33 13:19. | Acids and salty notes come out first, and more extraction reaches the sweet part 1:31. | Hedrick |
| Slightly sour, otherwise good | sour | Keep the grind and dose and let the shot run a little longer 4:34. | Raises the ratio and contact time without spending beans on grinder changes 4:34. | Hedrick |
| Sour but sweet, fast low-pressure light roast | sour | Extend the ratio towards 1:3 to 1:3.5 or grind slightly finer 9:46. | Past about 18% extraction the sharp acids fade and balancing compounds appear 9:46. | Hedrick |
| Sour, astringent citrus-peel finish on a light roast | sour | Push the extraction by grinding finer or raising the yield 26:14. | Sharp citric acidity signals under-extraction 26:14. | Hedrick |
| Sour gusher on an ultra-light roast | sour | Grind much finer, even to just off burr touch 38:59. | Very light roasts lose puck resistance quickly 38:59. | Hedrick |
| Sour or salty while hitting 9 bar on a processed coffee | sour | Go coarser at the same yield and use cooler water 20:51. | A very fine grind extracts unevenly, so parts of the bed stay under-extracted even when the average looks fine 20:51. | Hedrick |
| Bitter and sour at once, very slow shot | bitter | Go a couple of clicks coarser, keeping the dose and yield the same 6:43. | Grinding too fine causes channelling, with bitter paths and a sour remainder 6:13. | Hedrick |
| Bitter, dry, tannic despite a short or fast shot | bitter | Fix the distribution and puck prep before assuming over-extraction 23:52. | Channelled pockets over-extract while most of the puck under-extracts 22:52. | Hedrick |
| Watery, drying, bitter | bitter | Shorten the yield, or slow the flow slightly with the grind after checking the distribution 29:05. | The late part of the extraction is thin and bitter, and fines and channels add bitterness too 2:31. | Hedrick |
| Bitter, drying, over-extracted | bitter | Shorten the ratio or lower the temperature, and go coarser to speed up the flow 24:02. | Reduces the extraction and the harsh compounds 24:02. | Hedrick |
| Muddy, grimy, astringent at a normal time | bitter | Grind coarser and win back the extraction with the ratio or temperature 10:15. | Grinding too fine pushes fines through the basket and causes channelling 10:15. | Hedrick |
| Bitter dark roast | bitter | Lower the temperature, even to about 85 °C 19:27. | A lower temperature is gentler on dark, soluble coffee 19:27. | Hedrick |
| Dark roast with a drying finish and thin body | bitter | Keep the grind and stop the shot earlier (e.g. 32 g instead of 36 g) 15:58. | A lower ratio adds body and removes the over-extracted dryness 15:58. | Hedrick |
| Woody, fibrous bitterness on aged coffee | bitter | Go coarser, accept a fast shot at low pressure and lower the temperature 30:05. | The coffee was pushed too far, and losing CO2 has already lowered its resistance 30:05. | Hedrick |
| Dark roast salty, weak and boring after going coarse | sour | Go finer to about 20 to 23 s at 9 bar, with a ratio of 1:1.5 to 1:2 and cooler water 38:15. | Dark roasts extract fast, and extending the yield only adds dryness 38:15. | Hedrick |
| Too much acidity on a dark roast at about 24 s | sour | Grind slightly finer to reach about 28 to 30 s 13:56. | More contact brings out caramel and dark chocolate 13:56. | Hedrick |
| Tart, harsh finish on a fast light-roast shot | sour | Add about 0.5 g to the dose at the same yield 12:18. | Slows the shot, adds body and smooths the edges 12:18. | Hedrick |
| Thin or watery, wants more body | other | Shorten the ratio, or use a deeper bed or larger basket with a coarser grind 15:51. | Concentration and bed depth set the body, but watch for sourness at shorter ratios 15:51. | Hedrick |
| Shot far too slow (no drops by 10 s) | other | Grind much coarser 9:19. | The grind is too fine, and dark roasts especially need coarser settings 9:19. | Hedrick |
| Gushing in 10 to 20 s | other | Go a click or two finer 5:05. | Slows the shot into a workable window 5:05. | Hedrick |
| Too fast even at the finest setting | other | Open up the grind and use a bigger dose in a larger basket 29:36. | Grinds that are too fine clump and channel, which speeds the flow up 29:36. | Hedrick |
| New coffee runs much faster or slower at your usual setting | other | Let the time difference set the direction and size of the change. Much longer means coarser, and much shorter means finer 11:16. | Coffees differ in fines, so the time at a fixed setting predicts the change 11:16. | Hedrick |
| Shots slow down after switching from a light to a dark roast | other | Go coarser 22:28. | A dark roast grinds to a smaller peak at the same setting 22:28. | Hedrick |
| Shots suddenly run much faster after changing how you feed the beans | other | Re-dial finer 9:13 8:39. | Slow feeding gives a coarser grind with fewer fines 8:39. | Hedrick |
| Balanced but want more extraction | balanced | Try small amounts of RDT (about 5 to 10 µL per gram) and measure or taste 39:23. | Water reduces clumping, and the right amount depends on the grinder 39:23. | Hedrick |
| Shot on time but harsh and roasty (medium roast) | bitter | Lower the temperature about 2 °C, go one step finer and shorten the ratio slightly 3:49. | Medium roasts extract easily, and a finer grind with a shorter ratio cleans up the finish without losing extraction 3:49. | Hoffmann |
| Slightly harsh and sour shot | sour | Add 2 to 3 g of yield (e.g. 36 g to 39 g) 7:39. | More liquid raises the extraction, and small changes have a big effect 7:39. | Hoffmann |
| Very sour, far from good | sour | Grind finer even if it breaks your time target 6:04. | Strong sourness means under-extraction 6:04. | Hoffmann |
| Weak, hollow shot with a harsh finish and late gushing | bitter | Back the grind off slightly and break up the clumps 9:37. | These are signs of channelling 9:06. | Hoffmann |
| First shot after a big grind change runs fast | other | Purge about 3 to 5 g after big changes 12:10. | Retained coarse grounds get pushed into the next dose 11:08. | Hoffmann |
| Shot slows by about 10 s after starting RDT | other | Re-dial coarser 12:14. | On some grinders the water changes the flow without changing the measured particle size 17:22. | Hoffmann |
| Bean-to-cup shot sour | sour | Grind no more than one or two steps finer than the factory setting, then lengthen the output 6:38. | Fine grinds channel in these brew groups 2:01. | Hoffmann |
| Slightly sour espresso | sour | Grind one step finer, and once you're close, extend the ratio instead 4:09 8:46. | Finer slows the flow, and a longer ratio adds the later part of the shot to soften the acidity 8:46. | DGC |
| Bitter espresso | bitter | Stop the shot earlier or grind coarser 8:46. | Less of the bitter late part of the shot reaches the cup 8:46. | DGC |
| Results don't follow grind changes | other | Fix the puck prep with WDT or a blind shaker and a level tamp 10:48. | Uneven density causes channelling 9:46. | DGC |
| Decaf espresso runs fast | other | Grind finer but tighten the ratio 18:03. | Decaf is more soluble yet flows faster 18:03. | DGC |
| Swinging from choked to gushing on a flat-burr grinder | other | Approach the setting from the same side every time, in small moves 15:13 12:57. | Flat burrs have a narrow usable range 10:38. | DGC |
| Second shot runs slower than the first (on-demand grinder) | other | Purge about one shot's worth before the first shot of the day 10:41. | Stale grounds sit in the chute overnight 14:17. | DGC |
| Shot too acidic | sour | Lengthen the yield, e.g. from 40 g to about 45 to 46 g with a 20 g dose 4:35. | A longer pull balances strong acidity 4:35. | Rowsell |
| Harsh, astringent dark-roast shot | bitter | Switch to a falling-pressure profile and keep the ratio at 1:2 or less 3:32. | Tapering the pressure cuts astringency and lets the acidity through 3:32. | Rowsell |
| Shot about 46 s for 1:2 on a very fine-stepped grinder | other | Go six or seven clicks coarser 7:09. | Each click on a 1Zpresso J-Ultra moves the shot only slightly 4:03. | Chronicler |
| One click jumps from too slow to too fast (coarse-stepped hand grinder) | other | Keep the one click that works and fine-tune with the dose or tamp 7:24 26:10. | On a Timemore C3 each click moves the shot by about 15 s 26:10. | Chronicler |
| Astringent shot with clashing off-notes at high RPM | bitter | Slow the burrs from roughly 1500 down to 900 to 1000 rpm 10:18. | High speed gave harsh notes on that burr set 9:48. | Chronicler |
| Sour, under-extracted light roast | sour | Grind slightly finer, and if it persists, raise the yield 5:06. | Gives a dense roast more contact and extraction 5:06. | Sprometheus |
| Bitter, over-extracted light roast | bitter | Grind slightly coarser to shorten the shot, then reduce the yield 5:06. | Less contact lowers the extraction 5:06. | Sprometheus |
| Sour, thin and channelled despite grinding finer | sour | Tamp properly or set a deeper levelling depth before chasing the grind 1:42. | Compaction and headspace even out the flow, while the grind alone either chokes or channels 1:42. | Sprometheus |
| Shots crawl once a puck screen is added | other | Grind noticeably coarser 5:37. | The screen adds resistance, almost like a second tamp 5:37. | Sprometheus |
| Thin, bitter, flat 1:2 shot on a darker coffee | bitter | Go finer and stop at a 1:1 ristretto 2:32. | Stopping early skips the roasty late part and gives a sweeter, syrupy shot 2:32. | Sprometheus |
| Bitter shot with unimodal burrs at a traditional ratio | bitter | Pull faster and longer, e.g. 40 g or more in about 20 s 7:42. | With so few fines, grinding fine enough for a classic shot over-extracts 7:42. | Sprometheus |
| Punchy, overly bright light single origin at 9 bar | sour | Run at about 6 to 7 bar instead, going finer so the time holds 2:01. | The lower pressure gave more sweetness and less early channelling 2:01. | Sprometheus |
| Dry, astringent finish on a long shot | bitter | Grind slightly coarser, keep the dose and shorten the ratio a little 3:12. | Pulls back the over-extraction 3:12. | ECT |
| Thin, sharp washed light roast | sour | Go a little finer and cut the yield (36 g down to about 30 to 34 g) 7:27. | Adds texture, sweetness and balance 7:27. | ECT |
| Sour or salty light roast after good prep | sour | Add 1 to 2 °C (staying within 93 to 97 °C) before touching the grind 3:09. | Barista Alan finds steps of less than a degree make no noticeable difference 3:09. | ECT |
| Astringent light-roast shot despite good prep | bitter | Go coarser and pull to around 1:3 3:09. | A coarser grind reduces channelling, and the aim is balance rather than body 3:09. | ECT |
| Pressure falls short of the profile target (pressure-profiling machine) | other | Grind finer 6:09. | Too coarse a grind lets the flow run too high to build pressure 6:09. | Quan |
| Pressure overshoots, with few drops during pre-infusion | other | Grind coarser 7:15. | Too fine a grind chokes the machine 7:15. | Quan |
| Light-roast espresso tastes like battery acid | sour | Use a blooming profile (a bloom of 10 to 30 s at around 5 to 6 bar) and a longer ratio (1:4 to 1:5 is fine) 1:38. | The bloom builds sweetness and rounds the acidity 1:38. | Quan |
| Muddy light-roast shot on fast flat burrs | bitter | Cut the pre-infusion short, go a touch coarser, or bring the temperature and flow down 8:16. | The contact time or extraction is going too far 8:16. | Quan |
| Pressure spikes to 12 bar and the flow collapses | other | Go substantially coarser 9:47. | For that profile and dose the grind was too fine 9:47. | Quan |
| Shot runs fast and leans sour (under about 25 s for 40 g) | sour | Grind finer, then check the dose again 7:31. | A finer grind slows the flow and adds contact time 7:31. | Bluebird |
| Shot runs slow (about 32 s) and loses balance | other | Open the grind by about one step 13:37. | Shorter contact brings the sweetness and acidity back into balance 13:37. | Bluebird |
| Shot a little long and short of sweetness | other | Grind coarser for a faster flow at the same yield 10:33. | A faster shot tends to taste sweeter and more balanced 10:33. | Bluebird |
| Kenyan espresso sour and under-extracted | sour | Lengthen the ratio from 1:2 to about 1:2.5 4:04. | The extra extraction turns sharp acidity into sweetness 4:04. | Bluebird |
| Heavy or boozy shot from a heavily processed coffee | other | Pull it fast (about 22 to 23 s) and long (about 55 g from 20 g) 3:35. | Keeps the big flavours while staying clean 3:35. | Bluebird |
| Funky coffee shot running past its target (26 s against 24 s) | other | Grind coarser and drop the water to about 90 °C 5:06. | Pulls back the extraction and intensity 5:06. | Bluebird |
| Thin, muddy shots from a small basket | other | Keep the dose within the basket's range (14 to 16 g in a 16 g basket) and focus on prep 4:36. | An overfilled basket channels and extracts unevenly 4:36. | Bluebird |
| Light-roast shot chokes at the finest Encore ESP settings | other | Work in the lower middle of the 1 to 20 espresso zone 4:41. | The range is wide enough without going to the very bottom 4:41. | Bluebird |
Pour-over
| Symptom | Tag | Change | Why | By |
|---|---|---|---|---|
| Bitter, leathery, muted pour-over | bitter | Grind coarser 7:22. | Above about 21% extraction, harsh compounds start to dominate 7:22. | Hedrick |
| Bitterness at a long 1:20 ratio | bitter | Shorten the ratio or go slightly coarser 18:59. | A long ratio and a fine grind together push the yield into bitter territory 18:59. | Hedrick |
| Bitterness near boiling on a light roast | bitter | Brew at about 95 °C instead of 99 °C 7:40. | Less bitterness while keeping the good flavours 7:40. | Hedrick |
| Roasty bitterness on a fairly light coffee | bitter | Lower the temperature a few degrees and shorten the ratio 12:16. | Avoids pushing the extraction on a more developed roast 12:16. | Hedrick |
| Roast bitterness creeping in on a light coffee | bitter | Lower to about 88 °C and keep the extraction with more agitation or a slightly finer grind 10:13. | A lower temperature cuts roast bitterness while keeping the extraction 10:13. | Hedrick |
| Lingering astringency at very high extraction | bitter | Don't push past about 23% extraction 7:09. | Astringent compounds appear at very high extraction on some burrs 7:09. | Hedrick |
| Very light roast lacking sweetness | sour | Go hotter (about 96 °C), pour more aggressively, add a small swirl, or grind a bit finer 14:48. | Light roasts are harder to extract 14:48. | Hedrick |
| Ultra-light coffee under-extracting | sour | Raise the temperature (up to 93 °C), grind a little finer, lengthen the bloom and pour more turbulently 16:21. | Lighter, gently processed coffees are harder to saturate and extract 16:21. | Hedrick |
| Dense, very light coffee hard to extract | sour | Bloom for about 1.5 min and make the second pour aggressive 19:57. | Longer blooms raise the extraction 19:57. | Hedrick |
| Older coffee tastes hollow and drains fast | other | Lower the temperature, shorten the ratio, and pour harder or add coffee. Don't grind finer 26:43. | Aged coffee has less to give and over-extracts at the end 26:43. | Hedrick |
| Drawdown too fast | other | Swirl the slurry after the final pour 7:34 9:44. | Swirling slows the drawdown and settles fines against the paper 7:34. | Hedrick |
| Drawdown too slow | other | Pour in the centre or use a laminar pour, and give a small shake at the end 12:13. | Less agitation and clogging, and a more even bed 12:13. | Hedrick |
| Slow drawdown from a grinder that makes lots of fines | other | Grind very coarse and swirl after pouring 29:06. | Boulders sit on top, and a swirl pulls them into the bed 29:06. | Hedrick |
| Muddy cup from an espresso-oriented grinder | bitter | Feed the beans in slowly, then re-dial finer if needed 0:31. | Fewer fines and cleaner cuts 0:31. | Hedrick |
| Decaf clogging and over-extracting | bitter | Grind about two clicks coarser and use about 88 °C, a shorter ratio and gentle pours 39:38. | Decaf grinds finer at the same setting and makes more fines 39:38. | Hedrick |
| Watery, low-strength brew on a dark roast with filter-only burrs | sour | Switch to burrs suited to darker roasts (e.g. Timemore 078S instead of Turbo) 25:31. | Some filter burrs are tuned for light and medium roasts 25:31. | Hedrick |
| Pour-over empty, hollow and a little acidic | sour | Grind finer until bitterness appears, then step back slightly 10:45. | That point is about the best extraction for your setup 10:45. | Hoffmann |
| Pour-over dry and bitter | bitter | Grind coarser 4:35. | That points to over-extraction 4:35. | Hoffmann |
| Bloom muddy and soupy (too fine) | bitter | End the brew at your normal total time and top it up with hot water to your usual yield 4:08. | Finer grounds extract more per unit of liquid 4:08. | Hoffmann |
| Bloom dries out very fast (too coarse) | sour | Use five to seven fast pours that drain fully, plus an extra 25 to 50 ml pour if you like 7:15 8:47. | Turbulence and full drainage raise the extraction 7:15. | Hoffmann |
| Thin, acidic, astringent cup from a cheap hand grinder | sour | Suspect boulders. Grind a little finer and brew shorter, or upgrade 7:39 7:12. | Large pieces barely contribute to the extraction 10:45. | Hoffmann |
| New clarity grinder gives muddy, astringent, stalling brews | bitter | Season it with 3 to 5 kg before judging 10:16. | Unseasoned burrs have rough edges 13:56. | DGC |
| Stalled, bitter, astringent filter on a wide-distribution conical | bitter | Grind much coarser or use a filter-focused grinder 15:26. | Lots of fines slow the drainage and over-extract 14:56. | DGC |
| Weak, under-extracted pour-over at a very coarse setting | sour | Grind progressively finer and judge by taste rather than drawdown time 8:42. | The drawdown can stay the same while the extraction rises 8:42. | DGC |
| Astringency on filter at high rpm | bitter | Lower the rpm (around 90 on the Aries) 11:14. | A higher rpm added astringency on that grinder 11:14. | DGC |
| Drawdown far from about two minutes (centre-pour V60) | other | If it's much longer, go coarser, and if it's much shorter, go finer 5:38. | The recipe aims for a drawdown of roughly two minutes 5:38. | Rowsell |
| Silt layer on top of the spent bed | other | Grind coarser and pour more gently 4:45. | Too fine a grind or a rough pour stirs the fines up 4:45. | Chronicler |
| Bitter, sharp, astringent cup with a swampy bed | bitter | Pour with less force, using a gooseneck or a drip-assist device 4:30. | A heavy stream churns the bed and over-extracts 4:30. | Chronicler |
| Anaerobic coffee tastes of olives or cider vinegar | bitter | Grind much coarser and brew fast 2:01. | A fine grind over-extracts the funky compounds 2:01. | Chronicler |
| Light roast sour or empty with very soft water | sour | Try harder, more alkaline water (about 100 to 120 TDS) 2:31. | Some roasters develop to suit their local hard water 2:31. | Chronicler |
| Salty, sharp, rough cup from a "light" roast | bitter | Drop the water to about 87 °C 13:54. | The roast was darker than its label said 13:54. | Chronicler |
| Flat-bottom dripper stalls | other | Use a faster paper and dripper, which then let you grind finer 11:14. | Slow papers magnify differences in drainage with larger doses and agitation 11:14. | Chronicler |
| Hollow, bitter cup when skipping the bloom on fresh coffee | bitter | Add a 30 s bloom 5:39. | Trapped CO2 disrupts the extraction 5:39. | Sprometheus |
| Brew runs fast then stalls with SSP high-uniformity burrs | other | Grind coarser than normal and pour carefully, or keep the stock burrs for everyday use 4:34. | Those burrs make extra fines 4:34. | Sprometheus |
| Bitter or dry Switch cup (Emi Fukahori recipe) | bitter | Grind coarser than the 25-click Comandante starting point 3:03. | It's probably too fine 3:03. | ECT |
| Thin or too acidic Switch cup (Emi Fukahori recipe) | sour | Grind finer than 25 clicks 3:03. | It's under-extracted 3:03. | ECT |
| Chemex clogs or drains too slowly | bitter | Grind coarser and lift the filter to let air in 3:40. | Fines and the seal against the glass stall the drain and over-extract 3:40. | ECT |
| Bitter last part of the brew | bitter | Cool the final pour (to about 80 °C) 2:34. | By then the first two pours have done most of the extracting 2:34. | ECT |
| Muddy cup with heavy wet WDT | bitter | Stir the slurry less aggressively 12:54. | Heavy agitation can muddy the cup 12:54. | Quan |
| Grind too coarse for the recipe | sour | Add more wet WDT to make up for it 13:25. | Agitation raises the extraction and slows the drain 13:25. | Quan |
| Astringency on a low-dose Orea Z1 brew | bitter | Lower the kettle a few degrees (from 95 to about 93 °C) 2:33. | A finer grind at a low dose already extracts more 2:33. | Quan |
| Thin cup on a 10 g brew | sour | Back off the finer grind 3:03. | Too fine a grind with a shallow bed risks channelling 3:03. | Quan |
| Filter tastes blurred, a little tart and hollow, and runs long (3:15) | bitter | Go half a step coarser 5:30. | It points to over-extraction 5:30. | Bluebird |
| Drawdown well past about 2:30 | other | Grind coarser, and if it runs fast, grind finer 4:39. | Even with a guide in microns, grinders differ, so tune after the first cup 4:39. | Bluebird |
| Brew slower than wanted (2:45 instead of 2:30) | other | Shorten the gaps between pours 8:13. | Pour timing moves the total time without changing the character of the grind 8:13. | Bluebird |
| Hoop brewer stalls or runs very long | other | Grind coarser, don't agitate, and use rested coffee rather than very fresh or very dense coffee 8:10. | The filters are slow and the bed clogs easily 8:10. | Bluebird |
| Hoop brew takes 6 to 8 minutes | other | Switch to a faster paper, such as the NextLevel x Scott Rao high-flow paper, before grinding coarser 5:07. | Ceado's stock paper flows slowly, and it's the main cause of long, uneven Hoop brews. | Hoffmann |
| Flat-bottom brew too slow at the finer grind you want for sweetness | other | Switch to a 60° cone (an Origami with a V60 paper) and grind finer 4:00. | The cone keeps the flow moving 4:00. | Bluebird |
| Converting a cone recipe to a flat-bottom brewer | other | Grind coarser, shorten the gaps between pours, or both 1:32. | Flat bottoms drain more slowly 1:32. | Bluebird |
| Brew stalls after settling or stirring the bed | other | Settle the bed gently and leave it alone, and don't swirl a flat bottom 2:01 3:39. | Agitation carries fines down to the paper 2:01 3:39. | Bluebird |
| Dense washed Kenyan or Burundi short on sweetness | other | Grind coarser than usual 7:20 1:01. | These dense coffees still like less contact time 7:20 1:01. | Bluebird |
Immersion
| Symptom | Tag | Change | Why | By |
|---|---|---|---|---|
| Bitter, rough immersion or pressure brew | bitter | Grind coarser than the maker's finer suggestion 16:05. | A finer grind adds bitterness 16:05. | Hedrick |
| Sediment in a French press | other | Press slowly over 1 to 1.5 minutes and grind finer than usual 5:01. | Pressing fast damages the filter and lets sediment through 5:01. | Hedrick |
| Clever Dripper bitter and harsh | bitter | Grind slightly coarser 6:05. | Pulling back from over-extraction sweetens the cup 6:05. | Hoffmann |
| Clever Dripper hollow | sour | Grind finer, possibly much finer than you'd expect 6:05. | A hollow cup signals under-extraction 6:05. | Hoffmann |
| French press silty | other | Use a medium grind, skim, wait 5 minutes or more, and press only to the surface 1:36. | Lets the fines settle out of the cup 2:06. | Hoffmann |
| Silt in a French press cup | other | Check the plunger seals snugly 7:44. | A loose plunger lets fines past 7:44. | Chronicler |
| Astringent Switch cup with a closed-valve first steep | bitter | Shorten the first steep 14:48. | The first steep drives the extraction up 14:48. | Quan |
AeroPress
| Symptom | Tag | Change | Why | By |
|---|---|---|---|---|
| AeroPress bitter | bitter | Grind a little coarser or brew cooler 3:37. | It's probably too fine or too hot for that coffee 3:37. | Hoffmann |
| AeroPress sour | sour | Use the hottest water and grind a little finer 3:37. | Sourness means under-extraction 3:37. | Hoffmann |
| AeroPress harsh, astringent and cloudy | bitter | Press gently (well under about 0.7 bar) 19:27. | Pressing hard channels and forces material through the paper 18:57. | Hoffmann |
| Muddy AeroPress lacking clarity | other | Use two paper filters 4:11. | Improves clarity and sweetness 4:11. | Rowsell |
| Weak light-roast AeroPress | sour | Grind finer than for V60, use 99 °C water and extend to about 3 minutes 3:31. | Raises the extraction 3:31. | Rowsell |
| Salty, brothy or vinegary anaerobic natural | bitter | Discard the first concentrate, then add about 20 g back 9:44. | The early liquid carries the savoury, harsh compounds 9:44. | Chronicler |
| Channelling or uneven extraction when pressing | other | Press slowly and gently, for at least about 30 s 6:30. | An even flow through the coffee avoids channels 6:30. | Sprometheus |
| AeroPress slightly bitter and astringent, with flat clarity | bitter | Grind coarser and keep the rest of the recipe the same 6:09. | Pulls back the over-extraction for a cleaner, juicier cup 6:09. | Bluebird |
Moka
| Symptom | Tag | Change | Why | By |
|---|---|---|---|---|
| Moka harsh and bitter | bitter | Lower the heat, cut it once the coffee flows and stop before it sputters. Avoid a very fine grind 11:10 6:34. | Overheating and steam through the coffee add bitterness 3:31. | Hoffmann |
| Moka sour and under-extracted | sour | Grind finer and get more of the water through (at least about 60%) 4:32 12:44. | The extraction follows how much liquid passes through 13:45. | Hoffmann |
| Moka sputters before the yield you want | other | Turn the heat down once it starts flowing, and if that isn't enough, grind slightly coarser 10:06. | A grind that's too fine or too much heat speeds the pot up 10:06. | Hoffmann |
Cold brew
| Symptom | Tag | Change | Why | By |
|---|---|---|---|---|
| Cold brew weak and empty | sour | Grind much finer (moka or fine AeroPress level) at about 75 g per litre 9:44. | Coarse cold brew under-extracts and wastes coffee 4:39. | Hoffmann |
| Cold brew too light | sour | Grind finer or steep longer 10:49. | It's under-extracted 10:49. | ECT |
| Water runs straight through an AeroPress cold brew | other | Grind finer or brew inverted 3:46. | Keeps the water in contact with the coffee 3:46. | ECT |
Astringency
These rows come from Lance Hedrick's 2026 video on astringency. Rows tagged astringent are what Notchbook suggests after a brew you mark as drying. A few older rows above mention astringency too, under bitter or sour.
| Symptom | Method | Change | Why | By |
|---|---|---|---|---|
| Dry, puckering finish, like strong tea or a green banana | any | Extract less by grinding coarser or brewing a shorter ratio. 12:31 12:48 15:41 | The drying compounds extract slowly, so they build up when the extraction is pushed. | Hedrick |
| Drying light roast | any | Don't push the extraction high. Ease off with a coarser grind or a shorter ratio. 11:09 13:25 13:37 | Fast, very light roasts carry the most of these compounds, and they hit their ceiling sooner than most people expect. | Hedrick |
| Dry, harsh dark roast | any | Lower the water temperature or the ratio. 15:37 15:54 | On dark roasts the dryness is usually bitterness, and extracting less eases both. | Hedrick |
| Still drying after extracting less | any | Try a thicker paper filter. 17:04 17:15 | It may catch very fine particles (under about 5 µm) that feel drying or mask the cup. This is anecdotal and unproven. | Hedrick |
| Seems dry, but the cup is weak or sour | any | Taste a real drying reference first. If it isn't the same feeling, make a small tweak towards balance instead of extracting less. 1:10 12:55 16:10 | At a low extraction it's probably an imbalance that reads as dryness rather than true astringency. | Hedrick |
| Drying however you brew it | any | Accept that it may be the coffee. 17:48 | Some coffees are naturally more astringent than others. | Hedrick |
| Drying pour-over pushed to 23 to 24% extraction | pour-over | Bring the extraction down with a coarser grind or a shorter ratio, and aim lower on light roasts. 13:37 14:08 15:41 | The ceiling before astringency is lower than people used to think, especially for light roasts. | Hedrick |
Grinder behaviour
| Symptom | Tag | Change | Why | By |
|---|---|---|---|---|
| Grinder stalls on a light roast at fine settings | other | Start the motor before adding beans, feed slowly, and if it jams, go coarser to clear it 12:48 12:28 32:16. | Dense light roasts overload small motors, and fractured beans clog the burrs 12:28. | Hedrick |
| Grinder won't go fine enough after slow feeding or a burr swap | other | Re-dial finer. After a burr swap, find zero again and shim if necessary 9:13 25:32 11:16. | Slow feeding makes the grind coarser, and new burrs differ in thickness and seating 25:32. | Hedrick |
| Papery, dry, old-tea flavour | bitter | Clear the retained chaff and fines, and skip RDT for filter so the chaff clings and can be removed 35:14 11:46. | Retained chaff and fines that end up in the next dose taste papery 35:14. | Hedrick |
| Grinder seems to go finer over the months, and cups taste stale | bitter | Dry-clean the burrs and recalibrate zero 1:01. | Buildup shifts the calibration and taints the flavour 1:01. | DGC |
| Grinder safety cut-out trips on a dense light roast | other | Go coarser, raise the RPM and feed the beans slowly 11:14. | The auger overloads 11:14. | Rowsell |
| Stalls around 600 to 700 rpm on dense Ethiopian beans | other | Raise the speed to 1000 to 1400 rpm or change the burrs 8:37. | Aggressive stock burrs overwhelm the motor at low speed 9:07. | Chronicler |
| Shots suddenly fast (about 11 s) after fitting new burrs | other | Grind about four notches finer 3:05. | The fresh burrs produced a coarser grind at the same number 3:05. | Sprometheus |
| Can't reach espresso fineness out of the box | other | Fit the extra shims that come with it (Encore ESP Pro) or recalibrate zero until the burrs nearly touch 7:06 6:09. | Shims and zero calibration bring the burrs closer together 7:06. | Sprometheus |
Summarised in our own words from the creators' videos, with every point linked to the moment it comes from. Notchbook isn't affiliated with or endorsed by any of these creators, so please watch the originals for full context. Sources
Notchbook is a free app that remembers the grind setting that worked for each coffee, grinder, brew method and filter paper, and keeps a journal of every brew. Get it free on Google Play. The iPhone app is coming soon. More about Notchbook.