ACM 6.07 – Recap and Glossary

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  • The coffee refractometer needs to be cleaned and calibrated regularly.

  • Samples must be managed in a way that prevents water evaporating but also allows them to cool to room temperature when reading will be more accurate.

  • CO2 content is expected to be higher in dark roast coffees, while H2O content is expected to be lower in dark roast coffees.

    • The effect of these two presences in roasted coffee is to increase extraction yield values.

    • Scientific literature reports a 1.3-2.3% H2O content in low temperature, slow roasts (specialty).

  • When calculating extraction yield, the mass extracted from the coffee grinds will reduce the liquid retained.

New Words

  • Cellulose Matrix: the honeycomb-like arrangement of cellulose cell walls which in roasted coffee grinds is ripped open and made microporous. Cellulose is a polymer made of repeating glucose molecules attached end to end.

  • Deionised Water: pure water containing no minerals or suspended solids.

  • Physicochemical: pertains to the physics and chemistry of something.

  • Quenching: the practice of spritzing roasted coffee with water in order to speed up the cooling process.

  • Solenoid Valve: an electronically triggered filling valve, combining a sprung loaded rubber seal and a magnet to trigger the movement of water through plumbing — used in espresso and filter coffee equipment.


Links From the Text

Back to: Advanced Coffee Making > Refraction Action

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