Dec 8, 2008|

Dr. Brew, what causes an oily film to appear after brewing coffee, is this caused by the mineral or lack of mineral????

Walter Henry


Walter from Little Rock,

The oil film on the surface of brewed coffee is a natural occurrence. Certainly the quality and temperature of brew water can effect the amount of oil that is present. Brew water temperature above 205°F/ 96°C can extract more oil from the ground coffee. The most likely contributor to the oil is the degree of roast development. Many dark roasts (French / Italian roast) have oil drawn to the surface of the bean during roasting. Coffee oils also migrate to the surface of roasted beans as they release the carbon dioxide inside the bean during storage.

Happy Brewing,

Dr. Brew


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