Potential Use of Proximate and Fatty Acid Composition to Distinguish Between Cultured and Wild Largemouth Bass (Micropterus salmoides)

Abstract

Cultured largemouth bass (LMB) cannot be sold as food in some lucrative markets due to regulatory restrictions that protect wild LMB. Distinguishing between cultured and wild fish could open food markets for cultured fish. Wild LMB eat freshwater fish and cultured LMB eat diets high in marine fish meal and oil, which should produce differences in flesh composition. We analyzed the proximate and fatty acid composition of wild and cultured LMB muscle to determine the potential for distinguishing fish origin analytically. Protein and moisture were higher in wild fish, while lipid was higher in cultured fish. The n-3 and n-6 fatty acids, long-chain polyunsaturated fatty acids (LC-PUFA), and the ratio of n-3 to n-6 fatty acids all differed between cultured and wild fish. The n-3 to n-6 ratio and n-3 LC-PUFA were higher in cultured fish, while elevated arachidonic acid (20:4n-6) in wild fish was a key distinguishing feature.