Coffee Extraction
A complete introduction to extraction science: solubility, diffusion, flow, grind, temperature, time, water and sensory outcomes.
Extraction is selective
Brewing does not remove every component from coffee at the same rate. Soluble compounds move into water through a combination of dissolution, diffusion and fluid movement.
The major controls
Grind size, water temperature, contact time, agitation, brew ratio and water chemistry interact. Equipment geometry adds another layer, particularly for espresso and percolation brewing.
Concentration and extraction
A beverage can be highly concentrated without being highly extracted, or highly extracted without being very concentrated. This distinction explains why TDS and extraction yield should not be treated as the same metric.
Taste remains essential
Measurement helps explain a brew, but the goal is a beverage. Sensory evaluation should be used with recipe data to decide whether a change actually improved the cup.
Continue exploring
Green coffee
Follow coffee from plant and cherry through processing, drying, milling and storage.
Green coffee →Coffee chemistry
Explore the compounds and reactions that shape roasted coffee.
Coffee chemistry →Coffee extraction
Connect grind, water, temperature, time, concentration and extraction.
Coffee extraction →Coffee Knowledge presents technical subjects as an educational reference. Terminology, grading systems and production practices can vary by country, producer, equipment and commercial context.