Asked by: Anonymous
Meringue is made mostly from egg white, which is a mixture of proteins and water. Air whisked into the egg white becomes trapped and surrounded by a network of proteins. Adding sugar after the eggs have been whisked stabilizes this protein network, preventing it from becoming too stretched (which would result in a flat meringue). When cooked, water in the egg white evaporates, expanding the air bubbles and solidifying the protein network into a light, crisp meringue.
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