Working Paper 16
From Cherry to Cup: The Science of Coffee
October 2026
Abstract
Coffee is the most chemically studied beverage after water, yet the numbers that matter in the cup are scattered across food chemistry, agronomy, and trade literature. This paper assembles them into one quantitative account from species to serving. Green-bean chemistry differs first by species: canephora carries roughly twice the caffeine of arabica (15 to 25 versus 9 to 13 mg/g dry weight), more chlorogenic acids, and far less sucrose and oil, which explains the sensory gap between the species better than any single compound. Roasting conserves caffeine per bean while destroying most chlorogenic acids and nearly all sucrose; the "strength" of dark roast is manufactured bitterness (phenylindanes, diketopiperazines), not caffeine. Brewing parameters dominate caffeine delivery: a Vietnamese phin serving carries roughly 300 mg while a finjan of Arabic qahwa carries roughly 30 mg, a tenfold range set by dose, ratio, and bean species rather than by brew method mystique. We correct four persistent misconceptions with measurements, document 26 verified obscure, regional, and historical preparations with their extraction mechanisms, and close with an evidence-based exploration guide. All analysis was produced by Kilambi Research's quantitative research pipeline with AI assistance and verified against source data.