Mondo Knows Facts
Pressurised water creates coffee crema foam
High brewing pressure forces dissolved carbon dioxide into an emulsion of coffee oils
During espresso extraction, water under nine bars of pressure forces carbon dioxide gas trapped inside roasted coffee beans into solution. As the brewed liquid exits the portafilter into normal atmospheric pressure, the gas bubbles out of solution. The tiny bubbles become coated with coffee oils and melanoidins, forming a thick crema foam on top.
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Tags: coffee, espresso, crema
Pressurised water creates coffee crema foam: the short answers
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- High brewing pressure forces dissolved carbon dioxide into an emulsion of coffee oils. The figure is taken from Encyclopaedia Britannica, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
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