According to relevant test measurement reports, within 5 minutes after water boils, the nitrite content in the water rises slowly; the rise speeds up significantly after 5 to 10 minutes of boiling; and the nitrite content in the water can increase to 5 after 15 minutes of boiling. 9 times in minutes. A large amount of nitrite entering the human body can react with secondary amines to form nitrosamines, and nitrosamines are highly carcinogenic.

Making soup is just like boiling water. It doesn’t need to be simmered for too long, and it doesn’t need to be too thick. Since nutrients in many foods can only be dissolved by simmering them over a slow fire, they need to be simmered for a long time, but the various ingredients have more opportunities to react and may produce harmful substances. Other unfavorable ingredients are also easily concentrated due to the reduction in the amount of soup. , the soup cooking time is generally about two hours. The incidence rate of gastric cancer in Guangdong is quite high~~Everything has its limits.

During the long-term use of aged soup, it is necessary to constantly skim oil, filter out impurities and sediment, and constantly maintain the freshness of the old soup.