Encapsulation of Astaxanthin-enriched Camelina oil Extract in Ovalbumin/gum Arabic Stabilized Emulsion With/without Crosslinking by Tannic Acid

Abstract

Astaxanthin, as a high-value red carotenoid, has attracted much attention in recent years. The astaxanthin-enriched camelina oil extract can be a promising natural antioxidant and colorant. Therefore, effort is demanded to overcome the low oxidative stability and low water-solubility of the oil extract to broaden application fields. In this study, egg albumin (EA) and gum arabic (GA) were used as a combination to emulsify camelina oil extract. The resultant emulsions were further crosslinked by tannic acid, a natural phenolic cross-linker. The entrapment efficiency of astaxanthin in EA/GA stabilized emulsions was around 70%. The size of emulsions at different pH conditions was investigated, and the smallest diameter was observed at pH 7. But the best astaxanthin retention was achieved at pH 5 during storage at room temperature. After crosslinking by tannic acid, emulsions showed better protection of astaxanthin against UV light and heat. Our findings provided a promising emulsion system to encapsulate astaxanthin-enriched camelina oil.