The effect of copper on the color of shrimps: redder is not always healthier.

The objective of this research is to test the effects of copper on the color of pacific white shrimp (Litopenaeus vannamei) in vivo. Forty-eight shrimps (L. vannamei) were exposed to a low concentration of copper (1 mg/L; experimental treatment) and forty-eight shrimps were used as controls (no copper added to the water). As a result of this experiment, it was found that shrimps with more copper are significantly redder than those designated as controls (hue (500-700 nm): P=0.0015; red chroma (625-700 nm): P<0.0001). These results indicate that redder color may result from exposure to copper and challenge the commonly held view that highly pigmented shrimps are healthier than pale shrimps.