Research ArticleJ of Food Sci Nutr Res 2019; 2 (3): pp. 174-187
Omega-3 fatty acids are a family of polyunsaturated fatty acids (PUFAs) with beneficial health effects to humans if
consumed in required amounts. Fatty fish species are known to be rich in marine-based omega-3 fatty acids,
eicosapentaenoic acid (EPA, 20:5n-3), docosahexaenoic acid (DHA, C22:6n-3) and docosapentaenoic acid (DPA,
C22:5n-3). Sardines (Rastrineobola argentea) from Lake Victoria are a good source of health promoting omega-3
fatty acids. Open sun drying is a common and traditional sardine processing and preservation method. Due to their
chemical instability omega-3 fatty acids in sun dried sardines are prone to lipid oxidation during processing and
subsequent storage. This study investigated the use of clove (Syzygium aromaticum) water extracts as natural
antioxidants to protect omega-3 fatty acids against oxidative damage during storage of sun dried sardines. Lipid
oxidation was assessed by peroxide value, volatile secondary oxidation products and fatty acid profiles. The
antioxidant capacity of extracts was evaluated by total phenolic content, 1, 1-diphenyl-2-picrylhydrazyl (DPPH)
radical scavenging and iron (Fe 2+ ) chelating ability. Clove extracts resulted into significantly higher retention of total PUFAs, DHA, EPA and DPA at the end of 30 days storage period and lower concentrations of secondary lipid
oxidation products. This is an evidence of their enhanced oxidative stability in the real food system due to presence
of natural clove antioxidants.