coriander, garlic, red pepper, tomato flower, lettuce, soy sauce, vinegar, Chili oil and sugar are often added to cold preserved eggs.

Preserved eggs are bitter and astringent. You can add some vinegar and Jiang Mo to remove the astringency. Mainly because: preserved eggs are made of duck eggs through lime (alkali), which has a fishy and alkaline taste and feels bitter. Vinegar can neutralize alkali and ginger can remove fishy smell!

The pine flowers on the pine eggs are actually produced by a chemical reaction. The main chemical component of protein is a kind of protein. When eggs are kept for a long time, some protein in the protein will be decomposed into amino acids. The chemical structure of amino acid has an alkaline amino group -NH2 and an acidic carboxyl group -COOH, so it can interact with both acidic and alkaline substances. Therefore, when people make preserved eggs, they add some alkaline substances, such as lime, potassium carbonate and sodium carbonate, to the mud. They will pass through the pores in the eggshell and combine with amino acids to form amino acid salts. These amino acid salts are insoluble in protein, so they crystallize out in a certain geometric shape, forming beautiful pine flowers.

In addition, because a lot of protein in the yolk of preserved eggs is decomposed into amino acids, the yolk of preserved eggs tastes much fresher than that of ordinary eggs. Although preserved eggs are nutritious and delicious, they are too alkaline, so they should not be eaten more. Some preserved eggs smell of ammonia gas because of complex reactions such as amino acid decomposition. It is suggested that when eating preserved eggs, add some aged vinegar, which can sterilize, neutralize some alkalinity of preserved eggs and taste more delicious.

Reference: Baidu Encyclopedia, making preserved eggs.