Troubleshooting
Why Does My Coffee Taste Sour?
Under-extraction and sharp acidity
By Coffee In Cup Editorial TeamPublished 16 January 2026Updated 6 February 20265 min read
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Sourness is the first thing coffee gives up. If that is all you taste, extraction stopped too soon.
Most likely causes
Check these in order.
- Grind too coarse
- Water too cool
- Brew time too short
- Channelling through an uneven bed
The fix
Grind finer, make sure water is near 203 °F, and keep the coffee bed level.
Frequently Asked Questions
Is acidity the same as sourness?+
No. Pleasant acidity reads as fruit; sourness is sharp and unbalanced.
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