The cup
What we taste in a coffee, what chemistry says about it, how it is named and how the trade scores it. The composition of the bean and what heat makes of it come from the review by Yang and coauthors (Agriculture, 2026) and from the work of Grosch, Hofmann and Spadone; the vocabulary, from the World Coffee Research Sensory Lexicon (2016) and from professional training documents; the protocols, from the 2004 scoresheet of the Specialty Coffee Association and the Coffee Value Assessment that replaced it on November 5, 2024; extraction, from Lockhart (1957) and Gagné (2021). The level of evidence is indicated when it varies: peer-reviewed article, institute, trade press, commercial page.
The 18 sections of this plate
Each section has its own page. The first sentence says what you will find there.
- 01What green coffee containsA green bean smells of almost nothing and contains none of the aromas of roasted coffee.
- 02What heat makes of itTwo families of reactions govern roasting, and they are those of bread crust and caramel.
- 03Five tastes, and touchThe tongue distinguishes five tastes, not four: sweet, salty, sour, bitter, and umami.
- 04The nose, twiceAlmost everything we think we taste, we smell.
- 05Naming: from trade vocabulary to the wheelThe modern vocabulary was born with Ted Lingle, executive director of the Specialty Coffee Association of America.
- 06Acidity, six acids and a confusionAcidity is the taste that separates a complex coffee from a flat one, and the one that roasters disguise as “brightness” so as not to frighten anyone.
- 07How much citric acid is in a coffee? Six answersSince six acids have just been named, a simple question: how much of it is there?
- 08Cupping, where the gesture comes fromUntil the end of the 19th century, almost all the coffees bought and sold in the United States were judged on the appearance of the green or roasted bean.
- 09The protocolThe protocol the SCAA published in 2004 sets figures that the whole world adopted.
- 10The 2004 scoresheet and what 80 points are worthThe SCAA scoresheet, approved by its technical standards committee in 2003 and published in 2004 with the protocol, scores ten attributes on a scale of 6 to 10 in quarter-point steps: fragrance/aroma, flavor, aftertaste, acidity, body, balance, uniformity, clean cup, sweetness and overall impression.
- 11Five forms, five philosophiesThere is not one scoresheet but several, and the only way to find one's bearings is to ask, for each, which question it answers.
- 12When chemistry discriminates, and what it really discriminatesOne would like a chemical analysis to be able to say, in place of the cupper, whether a coffee is good.
- 13The Q GraderThe Coffee Quality Institute, a nonprofit created by the SCAA, launched the Q Grader program in 2004.
- 14Cup defects and their causeThe best-elucidated defect is rio, that medicinal, phenolic or iodine-like taste.
- 15What each link changesThe 2026 review makes it possible to say, link by link, what is established.
- 16Extraction: Lockhart, 18 to 22%, and what was made of itWhat ends up in the cup depends on two numbers that must not be confused.
- 17Instruments: what each one measures, and what it missesThe refractometer starts from a simple optical principle: light is bent when it passes through a liquid, and the angle of this deflection depends on what is in it.
- 18TodayThe 2004 scoresheet is no longer the standard. The SCA first surveyed 1,600 cuppers around the world.
Elsewhere on the site, the passages that deal with the same things as this page. Computed from the text, not picked by hand.