According to the “Peninsula Morning Post” report on March 24, within the demolition site, a woman dyed several baskets of white dead fish to yellow for more than ten minutes. The whole process happened to allow a netizen to take photos with a mobile phone. At 8 o''clock on the morning of the 20th, at the demolition site behind the building of the Entry-Exit Inspection and Quarantine Bureau of Liaoning Province, Harbour Plaza, Zhongshan District, Dalian, a woman took out two plastic bottles filled with red liquid and poured the red liquid into the bathtub. Inside, the water in the basin instantly turned yellow. Then the woman put the hollow plastic basket filled with fish into the bathtub and shake it. From time to time, she used both hands wearing plastic gloves to pick up the yellow water in the basin and showered the dead fish. After several times, the plastic basket was removed from Raised in the water, all the whitening dead fish became bright yellow.

　　 In recent years, there have been many reports of using dyes to dye fish to yellow, not just individual phenomena. As reported in the "Peninsula Morning Post" on April 12, 2007, some fishmongers openly processed yellow croakers with yellow dye water outside the gate of the Dalian Heizuizi seafood market. The dyed yellow croakers cost more than the normal yellow croakers in the market. Fish 1 to 1.5 yuan. Not only in Dalian, but also in other places, such as Linhai and Hangzhou, many dyed small yellow croakers and Yangzhou yellow croakers are also dyed... There are some similar reports, I will not list them one by one.

　　The yellow croaker and big head treasure sold on the market are mostly aquaculture. The color of the yellow croaker is much lighter than the wild yellow croaker. In order to impersonate farmed croakers as wild croakers, unscrupulous traders dyed their colors yellow and sold them at high prices. In addition, when the fish has not been sold for a long time and is not fresh, some vendors will also soak them with stains and preservatives, and then pretend to be fresh fish for sale. According to existing reports, the pigments used for dyeing fish include lemon yellow, paint, and unknown dyes.

How can I identify the dyed fish? The method is simple: wipe the fish body with clean toilet paper. If the toilet paper is stained, it means that the fish is dyed. In addition, you can scrape the fish scales by hand. If your hands turn yellow, it also proves to be stained. Another method is to put the fish in clean water. If the water turns yellow, the fish may also be dyed.

　　 In fact, these identification methods are just a matter of equity. I don’t think it is really possible to avoid buying dyed yellow croaker. Because unscrupulous traders can easily find pigments that do not fade after dyeing fish, there may be some unscrupulous experts who provide non-fading pigments (like melamine) for non-traders. A market without credibility is terrible, and consumers have no way to protect themselves.