Influence of oil phases on the digestibility and curcumin delivery properties of Pickering emulsions

Starch-based Pickering emulsions with four types of oil phases (coconut, corn, olive, and sunflower oils) were fabricated to compare their delivery properties for curcumin. The release rates of free fatty acids and the bioavailability of curcumin were investigated using an oral-gastric-intestinal in vitro digestion model. The results revealed that the emulsions prepared with corn oil exhibited the highest zero-shear viscosity (η ₀ ) and infinite-shear viscosity (η _∞ ) values, indicating its superior physical stability. After 108 h of ultraviolet light irradiation at 254 nm, the emulsion with corn oil showed the highest loading rate of curcumin. In the simulated small intestinal digestion, FFA release rates for emulsions with different oil phases were: coconut (30.74 %) > sunflower (15.06 %) > corn (12.67 %) > olive (12.38 %) oils. The curcumin bioavailability was: sunflower (78.01 %) > coconut (64.56 %) > corn (54.58 %) > olive (52.51 %) oils. The curcumin bioavailability increased significantly with the increase of starch concentrations.