Influence of O/W emulsion interfacial ionic membranes on the encapsulation efficiency and storage stability of powder microencapsulated astaxanthin

Abstract Astaxanthin is a powerful antioxidant with several benefits for human health. Unfortunately, its utilization is limited owing to its poor water solubility and chemical instability during food processing. The aim of this study was to develop a high-efficiency encapsulation system through the assembly of O/W emulsions ionic interfacial membranes to enhance the stability of astaxanthin during the spray-drying process and storage. The emulsions were prepared by the sequential adding of ι-carrageenan and chitosan on the surfaces of the lupin protein isolate (LPI)-coated oil droplets containing astaxanthin. The Taguchi method was used to determine the optimal spray-drying process conditions. The results showed that highly stable emulsions were prepared with 0.20% (w/v) of ι-carrageenan and 0.15% (w/v) of chitosan on LPI-stabilized (1% w/v) oil droplets. Optimal conditions for producing the powdered emulsion with the highest encapsulation efficiency (96.3%) were: 160 °C of inlet temperature, 4 mL/min of feeding rate, 20% (w/w) of total solids content and tertiary emulsion. The multilayer powdered emulsions obtained resulted in high astaxanthin retention during storage compared to a primary powdered emulsion. The powders obtained showed high water solubility (>90%). The results obtained showed that this astaxanthin powdered emulsions have a great potential for its application as a functional ingredient in foods.