Century Egg 之 松花纹

皮蛋, supposedly ‘leathered egg’, yet named as ‘century egg’ by the Westerners.  During the Ming Dynasty, it was known as 混沌子, which is beyond translation, even for Google translate.

Century egg also known as pine-patterned egg, a more accurate-translation from alternative Mandarin name 松花蛋. 

Some century egg have patterns on the surface of the yolk, which resemblance pine branches.  The pattern is believed to be crystal salts of amino-acids.

Century eggs are coated with a mixture of quicklime (calcium hydroxide 石灰), soda ash (sodium carbonate 碱面) and salt (sodium chloride盐).  Quicklime reacted with soda ash, and forms sodium hydroxides.... Sodium hydroxides then seep through the egg shell and reacted with the amino acids in the yolk, forming amino-acid salts.  It’s the crystallization of the amino-acid salts that form the pattern on the yolk surface.