Oil powders stabilized with soy protein used to prepare oil-in-fat dispersions

We report on the use of a soy protein stabilized, spray-dried oil powder as a vehicle for the introduction of unsaturated liquid oil in a continuous fat matrix. The sprat dried oil powder was mixed with the molten continuous fat phase in concentrations of 30, 40, 50 and 60% of powder. The static crystallization of the continuous fa phase resulted in the formation of oil-in-fat dispersions, as was visualized with light microscopy and cryo-SEM. The isolation of the liquid oil in the internal of droplets ensured that the continuous fat phase dominated the structuring of these newly developed oil-in-fat dispersions, which was Theologically demonstrated with amplitude sweeps. The elastic modulus of a 40% oil-in-fat dispersion (G'(LVR) = 3.54 +/- 0.731 *10(5) Pa) was not significantly different from that of the undiluted fa phase (G'(LVR) = 4.55 +/- 1.87 *10(5) Pa), even though the dispersion contained 40% more unsaturated oil. However, thixotropic tests revealed that the oil-in-fa dispersions are shear sensitive which can limit their applicability. The recovery percentage after shear of the undiluted fat was 39%, while the 30 and 40% oil-in-fa dispersion had a maximal recovery percentage of 19%. These findings provide a potential approach to reduce the saturated fat content of fat-based food products using only food-grade ingredients and traditional foot processing techniques. Nevertheless, further optimization of the emulsion formulation and preparation and of the spray drying process is essential to improve the shear stability of these oil-in-fat dispersions