Extraction time
Total duration of water passage through coffee. Espresso: 25-30 seconds. V60: 2.5-3.5 minutes. French press: 4 minutes. Cold brew: 12-24 hours. Key parameter linked to grind size.
Background & Context
Extraction time is the duration of contact between water and coffee grounds during brewing — one of three primary extraction levers alongside temperature and grind size. Longer contact time extracts more compounds from the grounds, increasing both TDS and extraction yield. The relationship is not linear: extraction rate is fastest in the first seconds of contact (when concentration gradient between water and grounds is greatest) and slows as equilibrium is approached. SCA brewing standards specify target times by method: espresso 25–35 seconds, V60 pour-over 2:30–3:30 minutes, Chemex 3:30–4:30 minutes, AeroPress 1–2 minutes, cold brew 12–24 hours. These times assume correct grind size for each method; if your grind is too coarse, extending time compensates but risks extracting undesirable late-extraction compounds.
Practical Use
In practical brewing, time is the variable that reveals whether other parameters are calibrated correctly. A correct grind and temperature should produce target TDS within the standard time window. If the shot pulls in 18 seconds (too fast), the grind is too coarse or the dose too low. If it takes 45 seconds (too slow), the grind is too fine, the dose too high, or the puck is channelling. For pour-over, if drawdown completes in 1:45 minutes, grind finer to slow it; if still running at 4:30 minutes, grind coarser. Time is the diagnostic output, not the target to aim for directly — let grind size drive time, not the other way around. Cold brew represents the extreme of time-compensated extraction: water at 4°C extracts so slowly that 12–24 hours of contact time are required to reach 18–22% EY. The resulting cup is chemically distinct from hot-extracted coffee — lower acidity, higher sweetness, minimal volatile aromatics — because cold temperatures selectively extract certain compounds while leaving high-acid, volatile-aromatic compounds largely unreached. This is time as a flavour selector, not just a strength controller.
Related Terms
Related terms: Extraction yield, Grind size, Espresso extraction, Brewing method, TDS.