It should be noted that the preserved eggs made by the traditional technology have high lead content, because lead oxide is used in the making process, which will play a sealing role and block the pores on the surface of the preserved eggs, thus preventing the strong alkali from further chemical reaction with protein.
With the development of technology, after 2008, the state issued a new preserved egg standard, which stipulated the lead content in it. Regular manufacturers have begun to use "lead-free technology" to make preserved eggs, that is, zinc chloride or copper sulfate is used instead of lead oxide, which can reduce the lead content and seal the holes.
According to the information released by the State Administration of Market Supervision in recent years, the lead in preserved egg products sampled rarely exceeds the standard. In short, as long as it is preserved eggs that meet the national standards, it can be safely eaten.
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In addition, preserved eggs should be purchased through formal channels, and products with complete packaging, gray surface, few black spots and no cracks should be selected.
Preserved eggs should be stored in a cool and ventilated place at a low temperature for no more than one month. It is best to eat the peeled eggs within two hours. If the preserved egg's protein is light green and has an odor, it means that it has gone bad and cannot be eaten.
People's Network-Are preserved eggs safe?