A FLUR field guide
Every off-tasting cup has a fix.
Tell us what you're brewing and what's gone wrong. We'll walk you through exactly what to change on your next pour.
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Common fixes
The short version, for skimmers. The tool above goes deeper.
Why does my coffee taste sour?
Sour coffee is under-extracted: the water didn't pull enough out of the grounds. Grind finer, bring your water up to 200 to 205°F, or give the coffee more time with the water. One change at a time.
Why does my coffee taste bitter?
Bitter coffee is over-extracted. Grind coarser, cool your water down to 195 to 200°F, or shorten your brew time. Stale beans also go bitter no matter what you change, so check your roast date.
Why is my coffee weak or watery?
You need more coffee or more extraction. Move to a 1:15 ratio (30g of coffee for 450g of water), grind finer, and make sure your water is actually reaching 200°F.
Why does my coffee taste flat or dull?
Usually under-extraction, sometimes stale beans. Grind finer and use hotter water first. If the beans are a month or more off roast, no setting will bring them back.
Why is my espresso sour?
The shot ran too fast. Grind finer, add a gram or two of coffee, or raise your temperature. A proper shot runs 25 to 30 seconds from the first drip.
Why is my espresso bitter?
Over-extraction. Grind coarser, drop your temperature, and stop the shot sooner. Bitterness at the tail of the shot means you let it run too long.
Why FLUR
The glass matters too.
Dialing in your brew only gets you halfway. Handblown borosilicate, shaped for the drink, finishes the job.
A new coffee recipe, every week.
One email a week. A recipe worth making, and nothing else.