Effect of enzymatic degraded polysaccharides from Enteromorpha prolifera on the physical and oxidative stability of fish oil-in-water emulsions

To explore the potential application of enzymatic degraded polysaccharides from Enteromorpha prolifra (EEP) as antioxidant in fish oils, a stable fish oil emulsion system incorporating EEP was established. Effects of emulsifier (Tween 80, gum arabic and lecithin) and EEP concentration on the physical characteristics of fish oil emulsions were investigated. The results indicated that Tween 80 was the best choice, and 1% (w/w) of EEP was the optimum concentration for the preparation of fish oil emulsions. Influence of EEP on the oxidative stability and physical stability of fish oil emulsions was compared with that of antioxidants V E and TBHQ by determining the physical properties, lipid hydroperoxide formation, secondary reaction products formation, pH and long chain polyunsaturated fatty acid content, during storage at 45 °C. The results indicated that the fish oil emulsion system (5% oil, 1% EEP and 1% Tween 80, w/w) possessed good physical and oxidative stabilities.