Preserved eggs, wrapped eggs in gray, wrapped eggs, etc. are China traditional flavor egg products mainly made of duck eggs. Preserved egg is an alkaline food with fresh, smooth and refreshing taste and unique color and fragrance.

When people make preserved eggs, they will add some alkaline substances into the soil, which will pass through the pores in the eggshell and combine with amino acids to form amino acid salts, which are insoluble in protein, thus forming beautiful pine flowers. The preserved egg protein of the finished product is blue-brown, brown or brown-yellow, translucent and elastic, and generally has a pine pattern on the surface. Before eating preserved eggs, remove the dirt on the surface, wash and shell them, slice them, put them on a plate and pour seasoning on them, or eat them directly.