Encyclopedia Category
The Science of Coffee
Coffee science explains why coffee tastes the way it does. Extraction chemistry, the Maillard reaction during roasting, acidity, solubility, and water mineral content all govern flavor. This category breaks down the chemistry and physics behind brewing, roasting, and tasting.
Extraction Chemistry
Brewing dissolves compounds from ground coffee into water. Different compounds extract at different rates: acids and fruit notes first, then sweetness, then bitterness. Balanced extraction lands all three in harmony.
Extraction yield, the percentage of coffee mass dissolved, typically targets 18 to 22 percent. Below that range tastes sour; above it tastes bitter and astringent.
Roasting and the Maillard Reaction
Roasting drives off moisture and triggers the Maillard reaction, where amino acids and reducing sugars brown and create hundreds of flavor and aroma compounds. Caramelization follows, adding sweetness and color.
The development time after first crack decides whether a roast tastes bright and origin-forward or deep and roasted. Roast level and development together shape the cup more than almost anything else.
All Coffee Science Articles
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Frequently Asked Questions
What is extraction yield in coffee?
Extraction yield is the percentage of the coffee's mass dissolved into the brew. The ideal range is roughly 18 to 22 percent for balanced flavor.
What is the Maillard reaction in coffee?
The Maillard reaction is the browning between amino acids and reducing sugars during roasting that creates many of coffee's flavor and aroma compounds.
What is TDS in coffee?
TDS, or total dissolved solids, measures the strength or concentration of the brewed coffee, separate from how much was extracted from the grounds.
Why does coffee taste sour?
Sourness usually means under-extraction. Acids extract first, so a short, cold, or coarse brew leaves the cup dominated by acids without balancing sweetness.
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