Fatty acid profile of one fatty fish using GC-FID and GC-MS analysis: comparative study

The aim of this study was to profile the fatty acids in smoked fish oil using two GC-FID and GC-MS. To achieve this, fish (Polydactilous quadrifilis) from Youpwe fishermen smoked and cold pressed to extract the oil. The oil obtained was used for fatty acid profiling through methylation using the MeOH/KOH method before injection into a Stabil Wax®-DA GC-FID column and a SP 2560 GC-MS capillary column. GC-FID identified 30 FAMEs, with palmitic acid (C16:0) being the most abundant. Biologically active fatty acids such as docosahexaenoic acid (DHA, C22:6n3) and eicosapentaenoic acid (EPA, C20:5n3) were also identified at levels of 3.73% and 13.36%. Of the identified FAMEs, 48.71% were saturated and 51.79% were unsaturated. Polyunsaturated fatty acids were less abundant than monounsaturated ones, with Ꞷ-3 dominating this class. GC-MS detection of FAMEs and other compounds identified 72 FAMEs, 11 methyl ester FAMEs and 5 other compounds. Among the FAMEs identified in this library were non-conventional fatty acids such as C17:3n3, C16:1n10, C17:1n7, C18:2n9 and C23:6n3. Of the identified FAMEs, 17 are saturated and 55 are unsaturated. Comparison of the GC-MS and GC-FID profiles shows a similarity in the proportions of saturated and unsaturated fatty acids.