In the process of making preserved eggs, quicklime and soda ash should be added, and the two are mixed together to be alkaline. Alkalinity can degrade protein to produce ammonia, and then ammonia combines with water to form ammonia water. The PH value of ammonia water is relatively high, basically 9- 10. So the burning sensation when eating preserved eggs is basically caused by ammonia water.
Mr. Wang, who lives in Guangdong, likes preserved eggs. One afternoon, he ate three in a row. Unexpectedly, before the third egg was finished, the tongue became numb and stiff, and the upper and lower palates seemed to be on fire. Mr. Wang hurried to the hospital. After examination, the oral mucosa was "chemical burn" and needed intubation treatment.