Stability of Fish Oil Encapsulated in Spray-dried Powders Coated with Starch Particles

n-3 Polyunsaturated fatty acids (PUFAs) have important physiological functions. Encapsulation by spray drying is a technique used to protect against oxidation of PUFAs. The present work aimed to investigate the effect of starch coating on the oxidation stability of spray-dried powders containing fish oil droplets. A mixture (wall material content : 22 wt%) containing maltodextrin (MD, dextrose equivalent (DE) = 25)) or sucrose, hydrolyzed casein (4 wt%), antioxidants (4 wt%) dissolved in water (40 wt%) and fish oil(30 wt%) was homogenized at 100 MPa using a high-pressure homogenizer. The emulsion was spray-dried into powders using a pilot-scale spray dryer with and without starch feeding near the atomizer. The apparent oxidation rate constant depended significantly on the surface-oil content and was larger for the MD-coated fish oil than for the sucrose-coated fish oil.