Eggs – a black, preserved egg called

eggs

I remember some eggs which the egg yolk is solid and black, but forgot the source(seems like preserved), what is it?(if any)

Best Answer

The current most common term in English appears to be "century egg", but it's also been known as a thousand-year egg or hundred-year egg.

It's typically produced by aging in a solution of table salt, calcium hydroxide, and sodium carbonate, but traditional methods involved less refined versions of those chemicals wrapped in clay (and some quantity of rice bran).

More details in this Wikipedia entry.

Century egg

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