By Harold McGee
An especially prized variant of pidan is one in which the aspic-colored white is marked throughout with tiny, pale, snowflake traceries. Such eggs are known as songhuadan, or “pine-blossom” eggs. The “blossoms” turn out to be crystals of modified amino acids, which the high alkalinity has broken off from the albumen proteins. They’re thus an index of protein breakdown and flavor generation, a delicate inscription of the mineral world on the blank orb of the animal, and an example of the unexpected delight that can lie hidden in the crudest of preparations.