On the afternoon of March 17, the official account of China Food Safety Net published an article titled "Yellow Swan Eggs Once Again Found to Contain Synthetic Pigments, Suspected of False Advertising." The report stated that products from Yellow Swan, a leading domestic brand of edible raw eggs, were once again found by the Wang Hai team to contain the synthetic pigment canthaxanthin (also known as carotenoid). This finding severely contradicts Yellow Swan's long-standing public commitment of "containing no synthetic pigments," raising suspicions of false advertising. The test results were obtained from a third-party testing institution with legal qualifications, commissioned by the Wang Hai team. Data indicated that the first batch of Yellow Swan edible raw eggs submitted for testing had a canthaxanthin measurement of 0.399 mg/kg.

China Food Safety Net noted that after its "China Food Safety Report" account reposted the coverage, Yellow Swan publicly issued a statement and a lawyer's letter questioning the publication. The company argued that the 0.399 mg/kg canthaxanthin residue should not be considered a synthetic pigment, citing "multiple literature sources indicating that 0.1–0.5 mg/kg can be judged as a natural level, not the result of artificial addition."

The article further mentioned that the second round of test results from the Wang Hai team directly refuted this claim. Yellow Swan eggs purchased offline from Yonghui Supermarket showed a canthaxanthin residue value of 1.65 mg/kg—more than three times the upper limit of what Yellow Swan itself declared as the "natural range." This data not only invalidates the company's claim of a "natural baseline value" but also strongly suggests the likelihood of artificial addition. If Yellow Swan insists that 1.65 mg/kg is natural, it would fundamentally contradict the industry's basic understanding of natural ingredients. If it admits the level exceeds the natural range, the company must confront allegations of either "illegal additive use" or "loss of control over raw materials."

China Food Safety Net emphasized that Yellow Swan has long publicly advertised its edible raw egg products as having "naturally yellower yolks" and "containing no synthetic pigments such as canthaxanthin." The repeated detection of canthaxanthin residue now suggests misleading advertising and consumer deception. Consumers are advised to stay vigilant, evaluate marketing claims rationally, and protect their legal rights in accordance with the law.