Skip to content

The CoffeeGlossary Editorial Cover

The definitive coffee reference, written in plain English.

1,247 entries across brewing science, green coffee, espresso extraction, latte art, and café craft — written by credentialed Q-graders, reviewed by an eleven-person editorial board, and updated every quarter since launch.

  • 1,247entries in the library
  • 11editors on the board
  • Quarterlyreview cadence
Brewing Science · n. · /ɪkˈstrækʃən jiːld/

Extraction Yield

The percentage of a coffee's total soluble solids that end up dissolved in the cup — the single number most home brewers under-track.

A brewer's notebook beside a finished pour-over, the page covered in extraction ratio calculations.

Etymology. Adapted from analytical chemistry — the "yield" of a solute under specific solvent, time, and temperature conditions — into specialty coffee by Illy and Navarini in the 1990s.

Working range. The Specialty Coffee Association identifies a target extraction yield of 18 to 22 percent — values outside that band tend to read as under- or over-developed to a calibrated palate, though brew parameters vary by equipment and origin.

How to measure. Two numbers are required: the total dissolved solids (TDS) of the brewed coffee, measured with a refractometer, and the mass of the dose and beverage. The formula is straightforward: %EY = (TDS × beverage mass) ÷ (dose mass × 100).

Added in the Last 30 Days

Fresh ink, still warm.

The library grows on a rolling cadence — between December 14, 2024 and today, our editors and contributors added the following terms. The glossary is not a static wiki.

See all 1,247 entries
  • Brewing Science · Jan 12, 2025

    Third Wave Dripper

    A flat-bottomed pour-over device with a single large outlet — designed to reduce channeling by equalizing flow across the bed.

    Read entry
  • Green Coffee · Jan 9, 2025

    Intracellular Fermentation

    Anaerobic breakdown of sugars inside the whole cherry before pulping — associated with heightened fruit-forward cup profiles.

    Read entry
  • Espresso · Jan 6, 2025

    Pressure Pulsing

    An extraction technique that alternates between elevated and ambient pump pressure to manipulate flow rate through the puck.

    Read entry
  • Café Operations · Jan 3, 2025

    Stocked-Out Etiquette

    A small-but-real set of service conventions for what to say (and not say) when a regular's favorite single origin is sold out.

    Read entry

The Editorial Board

Who writes the glossary.

Every entry is written by a credentialed specialist and reviewed by an eleven-person board. The board met first in March 2019 and reconvenes quarterly.

Meet the full board
  1. 01

    Lena Vasquez, Founder

    Former Portland roaster · Editor-in-Chief

    Founded CoffeeGlossary in March 2019 after eight years roasting on the wholesale side. Oversees voice, taxonomy, and editorial calendar.

    • SCA CSP Barista Level 2
    • 312 entries at launch
  2. 02

    Maya Okafor, PhD

    Brewing Science Lead · CQI Q-Grader

    Food scientist with a doctorate in sensory analysis from UC Davis. Owns the brewing-science domain: extraction, solubility, water chemistry, refractometry.

    • 4 Q-Graders on staff
    • 312 brewing entries
  3. 03

    Tomás Reyes

    Green Coffee Lead · WBC Finalist Judge

    Buys green coffee for a forty-roaster cooperative in Veracruz. Editorial lead on processing methods, defect taxonomy, and the Specialty Coffee Association green grading protocol.

    • 2019 WBC finalist judge
    • 238 green-coffee entries
  4. 04

    Hannah Kuusisto

    Espresso & Latte Art Lead · WBC Certified Judge

    Twenty-one years behind the bar, twice a Nordic Barista Cup judge. Steward of every espresso- and milk-texture-related entry — ratios, puck prep, and the geometry of a tulip.

    • WBC-certified judge
    • 196 espresso entries

Plus seven additional editors and reviewers across sensory analysis, café operations, and equipment. See the full board roster

If you've ever stood at a café counter, pointed at a word on a bag, and muttered is that even a thing — CoffeeGlossary has the answer, in language a human can read. It's the reference we cite when we're writing our own glossary pages.

As referenced in our own publishing notes — alongside Sprudge, Barista Hustle, Counter Culture, and Stumptown's staff reading lists.