Comparison of the Nutritional Composition of Three Underutilized Fish Species in Sri Lanka

Abstract Fish consumption is generally considered as healthy due to their nutritional benefits that they ensure food security in many low and middle-income countries. Especially the Omega-3 fatty acids and essential amino acids present in the fish had beneficial effects on the Coronary Heart Disease (CHD) and reduce the Protein Energy Malnutrition (PEM) in these countries. Being an island and expanding aquatic resources, Sri Lanka has plenty of fish resources, but, the consumption of small fish among the population has decreased in the country over the past 20 years. So, it is essential to be aware of the nutritional content of particular fish species that are assumed to be undervalued. This study, it was aimed to compare the nutritional composition of three local fish species namely, Amblygaster sirm, Sardinella brachysoma and Oreochromis niloticus. Proximate composition, pH and calorific values of the fish meat were determined by standard methods and other relevant protocols. The fatty acid profiles of oils of the fish were examined using the GC-MS method. Results showed that there were significant (p<0.05) differences among the three fish species with respect to the proximate parameters and fatty acid composition. When compared to the other two species, S. brachysoma exhibited the highest quantity of crude protein and fat, with 19.23% and 4.85% respectively. Among three fish species, the total mono-unsaturated fatty acid (MUFA) and poly-unsaturated fatty acid (PUFA) contents ranged from 31 to 38%; particularly, quantities of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were found to vary from 2.69 to 3.7% and 7.5% to 9.2%, respectively. Considering the Omega-6:Omega3 ratio, A.sirm (0.3), S. Brachysoma (0.69) and O. niloticus (6.5) were reported balanced values. In conclusion, these three fish species can be potential raw materials to produce high-value fish products.