Loading of fish oil into nanocarriers prepared through gelatin-gum Arabic complexation

Encapsulation of fatty acids/fish oils within complexes could overcome low water solubility and oxidation susceptibility of these essential oils when considering their incorporation into food products; besides, it can mask their undesirable flavour and odour. So, in this research, nanoencapsulation of omega-3 (ω3) fatty acids by gelatin-gum Arabic complexes was optimized through response surface methodology (RSM). The effects of three independent variables including gelatin concentration (33–66%), ω3 concentration (10–30%), and homogenization speed (10,000–20,000 rpm), on different responses i.e. particle size, moisture content, colour values, free oil, encapsulated oil, and encapsulation efficiency were determined. It was revealed that homogenization speed had the highest impact on particle size; at 10,000 rpm, the smallest nanocapsules with (26–114 nm) were produced. Moisture content of dried nanocapsules was between 4.2 and 7.3%, and gelatin concentration was the most important factor. Similarly, colour values were mostly affected by gelatin concentration and increasing gelatin ratio lowered L values and raised b values of powders. Encapsulation efficiency of powder particles was between 69.74 and 98.41%, and homogenization speed had the highest effect on this response (P < 0.01). SEM graphs revealed that the nanocapsules had rather smooth and fragile surfaces, with some porous structures.