Nothing ruins a morning faster than a bitter cup of coffee. If you’re asking why is my coffee bitter, there are several common culprits – and all of them are fixable.
7 Reasons Your Coffee Is Bitter (And How to Fix Them)
1. Over-Extraction
The #1 cause of bitter coffee. When water contacts grounds for too long, it extracts bitter compounds.
Fix:
- Reduce brew time
- Use a coarser grind
- Lower water temperature slightly
2. Water Is Too Hot
Boiling water (212°F) scorches coffee grounds, releasing harsh, bitter compounds.
Fix: Use water between 195-205°F. Let boiling water sit for 30 seconds before brewing.
3. Grind Is Too Fine
Fine grounds have more surface area, leading to faster extraction and bitterness.
Fix: Match grind size to your brew method:
- French press: Coarse
- Drip: Medium
- Pour over: Medium-fine
- Espresso: Fine
4. Stale Coffee Beans
Old beans lose aromatic compounds, leaving behind bitter, flat flavors.
Fix:
- Buy whole beans, grind fresh
- Use within 2-4 weeks of roast date
- Store in an airtight container away from light
5. Dirty Equipment
Coffee oils build up and go rancid, adding bitter, stale flavors to every brew.
Fix: Clean your coffee maker weekly. Descale monthly if you have hard water.
6. Too Much Coffee
Using too many grounds creates an overly concentrated, bitter brew.
Fix: Use the golden ratio: 1-2 tablespoons per 6 oz of water. A scale helps with consistency.
7. Dark Roast Gone Wrong
Dark roasts are naturally more bitter. If over-roasted, they taste burnt and ashy.
Fix: Try a medium roast, or look for quality dark roasts that aren’t charred.
Quick Diagnosis Chart
| Symptom | Likely Cause | Solution |
|---|---|---|
| Bitter + burnt | Water too hot | Lower temperature to 200°F |
| Bitter + hollow | Over-extraction | Coarser grind, shorter brew |
| Bitter + stale | Old beans or dirty gear | Fresh beans, clean equipment |
| Bitter + sour | Uneven extraction | Improve pour technique |
The Bottom Line
Bitter coffee is almost always caused by over-extraction, water that’s too hot, or stale beans. Start by adjusting your grind size coarser and checking your water temperature. These two changes fix most bitterness issues. If problems persist, clean your equipment and invest in fresher beans.
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