Microencapsulation of fish oil rich in EPA and DHA using mixture of Arabic gum and Persian gum through spray-drying technique

The microencapsulation of fish oil by the spray-drying technique was conducted using Arabic gum (AG) and Persian gum (PG) as wall materials. AG-to-PG ratios, including 29:1, 28:2, 27:3, 26:4, and 25:5 (%w/w), wall-to-oil ratios, including 5:1, 4:1, 3:1, 2;1, and 1:1, drying temperature (180, 190, 200, 210, and 220°C), and feed flow rate at high and low states were optimized using response surface methodology. Microencapsulation efficiency (MEE), moisture content (MC), peroxide value (PV), and particle size (PS) were determined. Results showed that the highest MEE and the lowest MC, PV, and PS were attained when 26:4, 4:1, 210°C, and high speed were considered, respectively. At this point, the MEE, MC, PV, and PS were 79.49%, 3.39%, 10.98 meq O₂/kg oil, and 39.05 µm, respectively. The microstructure of optimum microencapsulated powder exhibited no observable cracks, fissures, or pores while having a typical spherical and smooth surface. Microencapsulation of fish oil using a mixture of AG and PG showed higher oxidative stability associated with high MEE, low MC, and low PV at the final product. Moreover, the optimized emulsion formulation and drying conditions increased the storage stability.