Optimization of anchovy oil microencapsulation using wall materials: effects on oxidative stability and encapsulation efficiency.

Microencapsulation is widely applied to improve the stability of highly unsaturated oils; however, the effectiveness of encapsulation largely depends on the composition of wall materials. This study systematically evaluated the influence of different wall material systems on the encapsulation efficiency and oxidative stability of spray-dried anchovy oil powders. Maltodextrin, sodium caseinate, gum arabic, and whey protein were used individually and in binary combinations as encapsulating matrices. The resulting microcapsules were characterized in terms of encapsulation efficiency, surface oil content, and lipid oxidation indicators including free fatty acids, peroxide value, and thiobarbituric acid reactive substances. Wall material composition significantly influenced both oil retention and oxidative stability. The maltodextrin-sodium caseinate system showed the highest encapsulation efficiency (73.54%) and the lowest surface oil content (3.82%), whereas formulations containing whey protein exhibited lower efficiency (50.03%) and higher oxidation. The gum arabic-sodium caseinate combination provided the greatest oxidative protection, with the lowest free fatty acid (9.32%) and peroxide values (13.46 meq O₂/kg). These findings demonstrate improved encapsulation and oxidative stability relative to previous studies, ans represents the first systematic assessment of single and binary wall-material systems for stabilizing anchovy oil, therefore offering practical insights for spray-dried lipid delivery system design in functional foods and nutraceuticals.