Effect of High-Pressure Homogenization and Wall Material Composition on the Encapsulation of Polyunsaturated Fatty Acids from Fish Processing

Fish oil, a rich source of omega-3 polyunsaturated fatty acids (PUFA), is a vital nutritional component, but considering its susceptibility to oxidation, it could benefit from an effective encapsulation system. This study aims to optimize high-pressure homogenization (HPH) parameters (pressure, number of passes) and wall material composition to maximize the encapsulation efficiency (EE) of fish oil, using different concentrations of maltodextrin with Arabic gum or sodium alginate. Key metrics such as emulsion droplet size, encapsulation efficiency, color, and oxidation in the final freeze-dried product were evaluated. Optimal values were achieved at 60 MPa, resulting in the lowest mean droplet diameter (369.4 ± 3.8 nm) and narrow distribution (0.197 ± 0.011) of the fish oil micelles prepared with a mixture of Tween80 and sodium caseinate as an emulsifier, without significant oxidation after four cycles of homogenization, while 80 MPa led to the highest EE (up to 95.6%), but increased oxidation. The combination of 10% <i>w</i>/<i>w</i> Arabic gum or 1% <i>w</i>/<i>w</i> sodium alginate with 20% <i>w</i>/<i>w</i> maltodextrin achieved the highest EE (79.1-82.9%) and whiteness index (82.5-83.0), indicating neutral-colored well-encapsulated fish oil without oxidation, which is desirable for product stability. Selecting optimal HPH conditions and wall material is crucial for the encapsulation efficiency and oxidation stability of omega-3 PUFA delivered in dehydrated forms.