Decaffeination
Decaffeination removes most caffeine from coffee beans or brewed coffee while aiming to preserve flavor and other desirable properties.
Solvent extraction: A separation method that dissolves selected substances into a liquid solvent. Several commercial decaffeination processes dissolve caffeine from moistened beans using a solvent.
Decaffeinated coffee: Coffee from which most caffeine has been removed before roasting or brewing. It is the principal product made by decaffeination.
Regular coffee: Coffee made without a caffeine-removal step. It retains substantially more caffeine than decaffeinated coffee.
Coffee aroma: The volatile compounds responsible for coffee's smell, shaped by its beans, processing, roasting, and brewing. Some aroma compounds can be lost or altered during caffeine removal.
Supercritical carbon dioxide: Carbon dioxide above its critical temperature and pressure, where it has properties of both a gas and a liquid. This fluid selectively extracts caffeine from beans under pressure.
Instant coffee: Dried coffee extract that dissolves in water to make a beverage. Decaffeinated versions are produced by removing caffeine before or after extraction.
Caffeine-free beverage: A drink formulated without caffeine as an ingredient. Decaffeination usually leaves residual caffeine, unlike a genuinely caffeine-free formulation.
Coffee roasting: The application of heat to green coffee beans to develop their color, aroma, and flavor. Decaffeinated beans can roast differently because processing changes their moisture and structure.
Ethyl acetate: An organic solvent used in products, chemical synthesis, and extraction processes. Some decaffeination processes use it to dissolve caffeine from beans.
Cold brew coffee: Coffee brewed by steeping grounds in cool or room-temperature water for an extended period. Brewing can extract caffeine from beans, so decaffeination is distinct from choosing a cold brewing method.