Excipient emulsion prepared with pectin and sodium caseinate to improve the bioaccessibility of carotenoids in mandarin juice: The effect of emulsifier and polymer concentration

•Excipient emulsion was prepared with pectin and sodium caseinate alone or compositely.•All emulsions greatly improved carotenoids bioaccessibility in mandarin juice.•Carotenoid bioaccessibility was highly depended on emulsifier type and concentration.•Emulsion with lower pectin content was favored to increase carotenoid bioaccessibility.•Viscosity was the main factor affecting carotenoids bioaccessibility.