A comparative study of encapsulation of carotenoid enriched-flaxseed oil and flaxseed oil by spray freeze-drying and spray drying techniques

Encapsulation of carotenoid enriched flaxseed oil was performed by spray freeze-drying by using sixteen different emulsion formulations. Emulsions, which contain various concentrations of carotenoid enriched flaxseed oil (6, 9, 12 and 15% w/w) and ratios of maltodextrin/(pectin+wax) (3:1, 6:1, 9:1 and 12:1 g/g), were encapsulated to determine the emulsion formulation with the highest encapsulation efficiency. The best-chosen emulsion formulation was processed also with spray drying to compare the produced powders in terms of the encapsulation efficiency, moisture content, particle size, flowing and morphological properties. It was found that the spray freeze-drying technique had a lower encapsulation efficiency but better flow properties. The effect of carotenoids was discussed for both encapsulation techniques and oxidative stability of the powders at 45 d of storage. Moreover, the addition of carotenoids resulted in products that were more stable in terms of oxidation.