The Chinese government has arbitrarily decided that rainbow trout can now be labelled and sold domestically as salmon.

The questionable move follows complaints earlier this year that rainbow trout was being mislabelled as salmon and that fish buyers were being deceived.

A media report earlier this year caused a stir by revealing that rainbow trout for years had been sold as the similar looking fish. 

But instead of sanctioning vendors who sell trout while claiming it is salmon, the China Aquatic Products Processing and Marketing Alliance (CAPPMA), which falls under the Chinese ministry of agriculture decided to legitimise the practice. 

Rainbow trout and salmon look similar when filleted but trout live in fresh water and salmon are born in freshwater but then live in much of their lives in salt water. 

Salmon fillets being sliced inside a supermarket in ShanghaiCredit:
Qilai Shen/Bloomberg

In May, Chinese state media revealed that a third of fish sold as salmon in China was in fact rainbow trout from Qinghai province, the BBC reported. 

Consumers revolted over fears that trout is more prone to parasites but in apparent public relations spin, the CAPPMA ruled that in order to standardise the industry, salmon was now considered to the “umbrella name" of the “salmonidae” fish, a scientific category which includes trout. 

The hashtag #RainbowTroutBecomesSalmon has been trending on Chinese social media site Weibo. “The trout must be confused. After so many years its identity has suddenly been changed to a salmon,” said one user. 

“Let’s label the crayfish a lobster instead,” said another. 

But not everyone was so understanding about the change. 

The redefinition also goes against what average Chinese people believe to be salmon, Chen Shunsheng, a professor at Shanghai Ocean University, told the Supchina website.

“The rainbow trout is a freshwater fish. Calling it ‘freshwater salmon’ is stealing a concept,” he said.