Coloring Goldfish With Tomatos
When you go to the market to by fish, let's say salmon, do you pick out the reddest salmon of the lot? Most people do pick the reddest fish. Therefore, fish color has an economic value. Color also has an economic value when it comes to pet fish, because people seem to choose the ones with the brightest, strongest, clearest colors. Here, a research team from Akdeniz University in Turkey, attempts to change the color of goldfish.
Melanins, purines, pteridines, and carotenoids are pigment groups that naturally provide coloring to plants and animals. Commercial fisheries, long having recognized that those bright colorful fish sell, feed fish synthetic forms of these pigments to enhance their marketability. Two faculty members of the fisheries department of Akdeniz University recently presented a paper at The International Conference of Agricultural Engineering describing on their work using real tomato as a source of carotenoid to make goldfish more orange.
The researchers studied 255 goldfish separated into 3 groups based on their skin pigmentation and fed them twice per day 2, 4, or 6 percent tomato powder with their feed. After 3 months, the tomato feedings were found to be ineffective in changing the pigmentation of the goldfish. No need to try this experiment at home.