Residents in many southern provinces and cities like to eat squid, pickled vegetables, pickled yellow croaker soup and other dishes in their lives. From the point of view of food hygiene, although this combination is delicious, it is not good for human health if it is eaten for a long time. Because pickles produce some nitrite in the pickling process. According to the analysis, the content of secondary amine in squid and yellow croaker is 30 ~150mg/kg, and the content of secondary amine in dried squid is even higher, reaching 230mg/kg. Experiments have proved that if the body ingests secondary amines and nitrite at the same time, it will synthesize nitrosamines, a painful substance, in the human body. Therefore, when squid and pickles or pickles and yellow croaker are cooked together, it is easy to produce nitramine in cattle, and it is easy to cause tumors and cattle after long-term consumption.