1. Extreme neurotoxicity: Lead can damage the brain and nerves, making people mentally retarded, unresponsive, hyperactive, inattentive, hearing impaired, learning difficulties and dyskinesia.
2, cause anemia
3. Suppress immunity
4. Loss of appetite, unexplained abdominal pain, vomiting, diarrhea or defecation.
5, affect the absorption and utilization of minerals and vitamins. Lead to calcium deficiency, zinc deficiency, iron deficiency and so on.
Preserved eggs are a favorite food for many people, but some raw materials of preserved eggs contain lead oxide or salt lead, so the lead content of preserved eggs is much higher than that of fresh duck eggs and salted duck eggs. Children are more sensitive to lead than adults. The lead absorption rate of adults is 5%- 10%, while the absorption rate of children is as high as 50%. In addition, children's brain and nervous system are immature, and they are more susceptible to lead and affect their intellectual development. So parents should not give their children more preserved eggs.
Many people like to eat preserved eggs and meat porridge, but it's okay to eat less preserved eggs, and it's not good for your health to eat too much.
Because preserved eggs are made of duck eggs wrapped in soda ash, lime, salt and lead oxide, duck eggs contain lead, which may cause lead poisoning if eaten frequently. This will lead to insomnia, inattention, anemia, joint pain, mental retardation, brain function and other symptoms. In addition, lead will replace calcium, affect calcium intake, and may also cause calcium deficiency.
Hygiene and nutrition of preserved eggs
It is often said that preserved eggs can't be eaten. In fact, it is mainly the doubt that preserved eggs contain heavy metal lead, but there is no need to be too alarmed, because a little attention can be avoided when buying again. Remember to check whether there are black spots of different sizes on the surface of the shell. If there is, avoid eating it.
The key to making preserved eggs is whether the protein inside is completely gelled. Therefore, in the process of making preserved eggs, it must be soaked in a strong alkali solution to realize the denaturation of protein and produce special flavor and color. However, in order to avoid the deterioration of the finished product caused by re-liquefaction after gelation, lead oxide, copper sulfate and methionine are usually added to the alkali solution to prevent re-liquefaction. The suspected lead residue is the residue of this chemical in the eggshell.
Generally speaking, the nutritional value of preserved eggs is: rich in iron, methionine (an essential amino acid) and vitamin E (compared with eggs). Disadvantages: protein denatured by alkaline solution is not easily absorbed, and LAL (lysine alanine) in denatured protein has unconfirmed nephropathy in animal experiments.
Personally, preserved eggs can be used as a kind of food to increase the variety of daily diet and taste special flavor, but from the nutritional value, it seems that there are other better choices. As for the problem of lead residue, consumers can only judge by appearance at present, but I already know that many experts in the food industry have developed a method to keep the quality of preserved eggs by controlling the temperature without adding lead oxide. I believe that in the near future, consumers can eat preserved eggs without worrying about heavy metal residues.