Preparation of Functional Yoghurt Fortified with Fish Oil-In-Water Nanoemulsion

ALTHOUGH being one of the richest sources of long chain omega-3 fatty acids, its stringent odor, high susceptibility to oxidation and hydrophobicity make fish oil application in food formulae very restricted. The main objective of this study was to fortify yoghurt, with fish oil nanoemulsion to increase its nutritional benefits. Olive and orange oils as well as alpha-tocopherol were also used in the preparation of the nanoemulsion to enhance the oxidative stability and palatability of yoghurt. Whey protein isolate (WPI) was utilized in different concentrations as a more safer emulsifier. Different characteristics of the prepared nanoemulsion like droplet size, polydispersity index (PDI), zeta potential, turbidity, and physicalparameters were assessed. The prepared nanoemulsion was then used to prepare yoghurt and its physicochemical and sensory attributes were examined. The oxidative stability of the incorporated fish oil was greatly improved as indicated by retention of polyunsaturated fatty acids (PUFA) content which was accounted to be 90.40 and 85.17 % for nanoemulsion fish oil (NFO) and plain fish oil (FFO) yoghurt samples respectively. Generally, Results indicated that yoghurt fortified with nanoemulsified fish-olive oils (NFO) gave closer characteristics to normal yoghurt and had better acceptability and sensory attributes than that fortified with plain fish-olive oils which let the door opened for more application of nanoemulsified fish oil in food formulations.