Grind Size Science
How particle distribution affects extraction and flavor in your coffee.
The grind size of your coffee beans is one of the most critical variables in brewing exceptional coffee. Understanding how particle distribution affects extraction can transform your daily brew from mediocre to extraordinary.
Understanding Particle Distribution
When you grind coffee, you create particles of varying sizes. Even the best grinders produce a distribution of particle sizes, not uniform particles. This distribution dramatically affects how water extracts compounds from your coffee.
Smaller particles have more surface area relative to their volume, leading to faster extraction. Larger particles extract more slowly. The key is finding the right balance for your brewing method.
Grind Size by Brewing Method
- Espresso:Fine grind (200-300 microns) for 25-30 second extraction
- Pour Over:Medium grind (500-800 microns) for 2.5-3.5 minute brew
- French Press:Coarse grind (700-1000 microns) for 4-5 minute steep
The Impact on Flavor
Grind size directly affects extraction rate and, consequently, flavor. Too fine, and you risk over-extraction, resulting in bitter, astringent coffee. Too coarse, and you'll get under-extraction, leading to sour, weak coffee.
The ideal extraction yields a balanced cup where sweetness, acidity, and body harmonize. This typically occurs between 18-22% extraction yield, which is heavily influenced by your grind size.
Choosing the Right Grinder
Burr grinders produce more consistent particle sizes than blade grinders. Flat burrs create a bimodal distribution with distinct peaks, while conical burrs produce a broader distribution. Each has its advantages depending on your brewing method and taste preferences.