What is the principle of making preserved eggs?

The main chemical component of egg protein is a kind of protein. When eggs are kept for a long time, some protein in protein will break down into amino acids. The chemical structure of amino acid has a basic amino group -NH2 and an acidic carboxyl group -COOH, so it can interact with acidic and alkaline substances.

Therefore, when people make preserved eggs, they will deliberately add some alkaline substances to the mud, such as lime, potassium carbonate and sodium carbonate. They will pass through the holes in the eggshell and combine with amino acids to form amino acid salts. These amino acid salts are insoluble in protein, so they crystallize in a certain geometric shape to form beautiful pine flowers.

Extended data:

Pick a safe preserved egg

The first step: put the preserved egg in the palm of your hand, just shake it, or it will be bad without shaking it;

The second shake: put the preserved egg in your ear and shake it gently. No sound is good, and sound is bad, which may be rotten eggs;

Third, look at the shell: the eggshell is complete, gray, with few spots, and there are black spots on the surface of the eggshell, indicating that the preserved egg has high lead and copper content; There are cracks in the shell, and too much alkali and bacteria may permeate during processing;

Taste: The protein is blue-brown, brown or brownish yellow, translucent and elastic, generally with pine pattern. Egg yolk is dark green or blue-black, with orange-red center, which has the fragrance of preserved eggs and no peculiar smell.

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