Antioxidant Effect of Plants Aqueous Extract on Lipid Stability of &i&Oreochromis niloticus&/i& during Traditional Sun and Smoke Drying in Far-North Cameroon

摘要

Fishes are suitable for sun drying and smoking. But their high contains of unsaturated fatty acids mak e them very prone to lipid oxidation. However, some plants are rich in natural antioxidants and have been shown to be potent inhibitors of lipid oxidation during processing of meat. The effect of three aqueous plants extracts on lipid stability of Oreochromis niloticus collected in Far-North Cameroon during processing was evaluated. Results show the high nutritious of these fish with high levels of proteins, lipid and ash (71.02 % , 13.71 % and 10.65%, respectively). It has been observed that oleic acid (C18:1), followed by palmitic acid (C16:0) and linoleic acid (C18:2) are the most dominant fatty acids present in Oreochromis niloticus lipids. Their lipid also showed a much higher content of omega-3 polyunsaturated fatty acids (PUFA) compared to omega 6 PUFA. The total phenolic contents (TPC) of the three plants ranged from 12 , 150 to 16 , 050 mg/100 g. The leaves of Moringa oleifera exhibited the higher content of TPC. The results of iodine, peroxide value and thiobarbituric acids test were revealed that the aqueous extracts of the tree plants had antioxidant properties. These plants extracts inhibit lipid oxidation of Oreochromis niloticus during processing. Increasing of the concentration of plant extracts enhanced their antioxidant activities and the highest oxidation inhibitor was obtained at 30 g/l. Moringa oleifera leaves inhibit highly the lipid oxidation of Oreochromis niloticus .