Coffee common sense crema in a cup of ESP is actually made up of grease and foam

Last updated 2026-09-29 — The crema in a cup of ESP is actually made up of grease and foam, while grease is divided into two forms. The oil is liquid and the fat is solid. The presence of grease can destroy the structure of the foam and cause crema to disappear quickly in a few minutes. Since the surfactant in coffee is dissolved in water, the surfactant of the grease surface will be pulled off the surface of the foam together with the water, causing the foam to change.