Farmed Fish to be Fed GM Tomatoes Containing Bacterial Gene

Farm-raised salmon and trout may soon be fed tomatoes that were genetically modified with a bacterial gene.




Salmon and trout living in the wild eat foods, like crustaceans and insects, that naturally contain pigments.  Those pigments turn their flesh pink or red. Farm-raised fish, on the other hand, don’t have access to those natural sources of food.  Instead, they are often fed dry pellets that can contain a wide variety of ingredients, including: soy, corn, canola oil, poultry, and antibiotics.

Consequently, the flesh of farm-raised fish can be pale pink, white, or even gray.  So, they are often fed dyes to make the fish look like wild-caught fish.  The dyes are commonly derived from petroleum or more “natural” sources like algae or pulverized crustaceans.

But, now there’s a new option – a “natural” dye from genetically modified tomatoes.




Tomatoes naturally produce carotenoids, which give them a red color.  But, the concentration wasn’t high enough to be used as a dye in fish food.  So, scientist added bacterial DNA (associated with ketocarotenoid production) to a tomato, forcing it to produce more of the colorful compounds.  But, the level of the coloring agent still wasn’t high enough.  So, that genetically modified tomato was crossed with a tomato that is very high in beta-carotene.  The result was a genetically modified tomato that produced high levels of the desired colorful compounds.

The genetically modified tomatoes were grown and freeze-dried in the United Kingdom and then shipped to Germany where they were turned into a powder and added to the feed for farmed trout.


What You Can Do:

1. Choose wild caught varieties of fish.

2. If you choose to eat farm-raised fish, ask which chemicals were used to color the flesh.












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