Characterization and emulsifying properties of aquatic lecithins isolated from processing discard of rainbow trout fish and its eggs.

This study investigates the characterization and emulsifying properties of different type lecithins. Emulsifying properties of lecithins isolated from rainbow trout egg (RL) and trout processing discard (WL) were compared with the soybean (SL) and hen egg yolk (HL) lecithin in sunflower-fish oil O/W emulsion systems. The phospholipid contents of RL and WL were significantly higher than those of HL and SL. The higher phospholipid contents in RL and WL resulted in lower droplet size (18.3-20.5 μm), higher viscosity (2.37-2.51 mPa.s) and higher physical stability (78.11-75.33) of emulsions. The linoleic acid (C18:2) was the most abundant PUFA in terrestrial origin lecithins (HL and SL), whereas DHA and EPA, a valuable omega-3 fatty acid, were the major PUFAs in aquatic origin lecithins (RL and WL). RL and WL formed more stable emulsions than HL and SL. This study provides valuable information for utilization of RL and HL as emulsifier in emulsion systems.