The Science of Coffee Extraction
Understanding the chemistry behind the perfect cup
OTBy OnBrew Team
July 21, 20252 min readThe Chemistry of Coffee Extraction
Coffee extraction is a complex process that involves dissolving various compounds from coffee grounds into water. Here's a detailed breakdown:
Key Compounds in Coffee
| Compound | Extraction Time | Flavor Profile |
|---|---|---|
| Acids | First 20% | Bright, fruity, citrus |
| Sugars | 20-40% | Sweet, caramel |
| Oils | 40-60% | Body, mouthfeel |
| Bitter compounds | 60%+ | Bitter, astringent |
Factors Affecting Extraction
- Water temperature (195-205°F ideal)
- Grind size (finer = faster extraction)
- Brew time
- Water-to-coffee ratio
- Agitation
Extraction Chart
The ideal extraction window is between 18-22%:
- Under-extracted