The effects of<i>Spirulina platensis</i>meal on proximate composition, fatty acid profile and lipid peroxidation of rainbow trout (<i>Oncorhynchus mykiss</i>) muscle

Abstract

This study evaluated the effects of diets containing 0, 25, 50, 75 and 100 g kg−1 Spirulina platensis on proximate composition, fatty acid profile and lipid peroxidation of rainbow trout (Oncorhynchus mykiss). Supplementation of S. platensis did not change moisture and protein contents, but fish fed 50 and 100 g kg−1 S. platensis had lower muscle lipid content than those fed control diet (P < 0.05). Fish fed 100 g kg−1 of S. platensis contained lower percentages of saturated and monounsaturated fatty acid and a higher percentage of polyunsaturated fatty acid than those fed control diet (P < 0.05). The n-3/n-6 ratio of the fatty acid increased and muscle atherogenic and thrombogenic indices were significantly decreased as the dietary supplement of S. platensis increased. Furthermore, lipid peroxidation of the fillet significantly decreased with increasing dietary S. platensis at 4 °C and at −20 °C (P < 0.05). The results of this study show that supplementation of S. platensis to the diet improves muscle quality of the rainbow trout.