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An eggshell looks solid, but it contains thousands of microscopic pores that allow gases to move through it. Because of these pores, eggs can pick up strong odors from foods stored nearby, particularly when the shell or surrounding environment allows odor compounds to penetrate.
This is one reason eggs are better kept in their carton rather than beside strongly scented foods.
The carton also helps reduce moisture loss and protects the shells from damage. An apparently sealed egg is actually interacting with its surrounding environment.
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