2. From the perspective of traditional Chinese medicine: ducks and duck eggs are cold, which will improve the coldness after pickling; Chicken and egg are both fire, and salting again will affect people's health because it is too uneven.
3. Seasonal perspective: There are plenty of duck eggs in specific areas and seasons, and there is a phenomenon that they can't be eaten. For the convenience of preservation, salted duck eggs and preserved eggs exist.
Salted duck eggs:
Salted duck egg shell is blue, round and smooth in appearance, also called green egg. Salted duck egg is a kind of reproduced egg with unique flavor and convenient eating. Salted duck eggs are good food with good color and flavor.
In the Qing dynasty, there were many workshops near the temple, processing preserved eggs and green fruits (salted duck eggs) and transporting them to Beijing, Tianjin, Baoding and other places by land and water, which were very popular in the market. Some products are also exported overseas. Among them, red hearts and salted eggs have a long reputation. They are salty and delicious, and their fragrance is overflowing. They are the best products for supplementing calcium in summer, and the shelf life at room temperature is 100 days.
The product is characterized by red heart and rich nutrition. Rich in fat, protein and various amino acids needed by human body. In addition, salted duck eggs are rich in inorganic salts such as calcium and iron, which are higher than those of eggs and fresh duck eggs, and are good foods for supplementing calcium and iron in summer.
A simple identification method for selecting salted duck eggs is that the shell of good quality salted eggs is clean and slightly shaken, and after the eggshell is peeled, it is salty with oil. When you pick it with chopsticks, the butter comes out and the yolk is layered. The color of the next layer is darker and redder. However, the shell of inferior eggs is dark in color with white or black spots, which is easy to break and has a short shelf life. The protein is soft, rotten and salty after peeling.