Ice Coating, a Fish’s Story of How Some Chinese Businesses Play with a Rule or Law

By Gang Xu       May 2, 2019

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Its name is yellow croaker, a delicacy on Chinese dining table. It is prized, of course.

The fish was once an abundant commercial fish in the East China Sea. Most people of my age from Zhejiang Province or Shanghai would have fond childhood memories of its tender texture and rich flavor. However, it almost became extinct in the late 1970s, due to overfishing. The fish started showing up in food markets again many years later, but most was farmed. ​Now many Chinese food markets in America sell farmed yellow 

croaker, ​imported from China in frozen state, some individually wrapped and sealed.
 
Although farmed yellow croaker doesn’t taste as delectable as the wild one, every once in a while, I would indulge my nostalgia and pick up a yellow croaker from the freezer of an Asian food market.

Then again it would be a mixed experience. One day I decided to quantitate my experience.
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• This was the fish just taken out from its plastic wrap and placed on a plate; it was heavily coated with ice. On a digital kitchen scale, the frozen fish and the plate together weighed 1304 grams.

• After being left at the room temperature for about 4 hours, the fish thawed. The fish, the melted ice, and the plate weighed 1306 grams. The 2 gram increase was likely from the moisture in the air that condensed over the cold surface of the frozen fish during the defrosting process.

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• After the water—the melted ice—was discarded, the fish and the plate weighed 1122 grams.

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• After the fish was removed, the plate weighed 469 grams.

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Now here are the maths:
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• The unadulterated fish weighs: 1122-469 = 653 grams
• The ice-coated frozen fish weighs: 1304-469 = 835 grams
• The ice coating of the frozen fish weighs: 835-653 = 182 grams
• The percentage of ice in the frozen fish: 182 x 100/835 = 21.80%

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Two Chinese trade organizations in 2013 issued a joint order, dictating that the ice content of seafood shall be no more than 20%. My measurements clearly establish that the ice content of the fish exceeds the trading standard, but to what extend?

• The degree of infraction: [(182 x 100/835)-20%]/20% = 8.98%, within 10% margin of error, still quite exoneratable, isn’t it?

​Oh my goodness! I could not help but exclaim an admiration: How smart, mathematically!

But why ice-coating in the first place? It wasn’t like this 10 years ago.