Preparation And In Vitro Digestion Of Nanocellulose-Algae Oil Pickering Emulsion

Pickering emulsification technology has attracted great attention in food industry due toits characteristics including green,safety and efficiency.Nanocellulose is a good emulsion stabilizer in Pickering emulsification technology highlighted with high purity,polymerization degree,crystallinity,hydrophilicity and transparency.In.this paper,by following the seaweed oil was emulsified by the emulsion stabilizer including nanocrystalline cellulose(CNC)and nanofibrous cellulose(CNF)(aqueous phase:oil phase was 7:3 v/v),the physicochemical properties of the emulsions were analyzed.The results showed that both CNC and CNF could contribute the seaweed oil to forming a stable oil-in-water Pickering emulsion.However,the emulsion stabilized by CNF had lower particle sizes(D32 from 1.80 to 2.25 ?m and D43 from 1.73 to 2.29 ?m)compared with that stabilized by CNC.Besides,the concentration of CNC did not obviously affect the yield of primary oxidation product(peroxide)and the secondary oxidation product(reactant of thiobarbituric acid)of the emulsion with the concentration of CNF played a negative role,resulting in the CNF tightly adherent on the grease.In order to improve the stability of Pickering emulsion,by blending the 0.25 wt%hydroxypropylmethylcellulose(HPMC)with 0.5 wt%nanocellulose,.The physicochemical properties of the emulsion prepared,and thenemulsifying the seaweed oil(aqueous phase:oil phase was 7:3V/V).The results showed that the emulsion formed by HPMC and nanocellulose was more stable than that formed by pure nanocellulose within 30 days.Furthermore,the primary and the secondary oxidation product of the emulsion were slightly reduced with HPMC being added.To decrease the oxidation rate of emulsion,tannin was added(0.25 and 0.5 wt%)into it,and the physicochemical properties of the emulsion were also analyzed.The results showed that the tannin could significantly improve the stability of the emulsion,with the the primary oxidation products and secondary oxidation products decreasing.This phenomenon was contributed to the attachment of tannin on the surface of the nanocellulose.Finally,the in vitro digestion behavior of the emulsion was investigated.The results indicated that the particle size of the emulsion digested by intestinal juice was smaller than that in the gastric juice.Moreover,the nanocellulose-stabilized Pickering emulsion could effectively reduce the release rate of free fatty acids.In summary,CNF shows better emulsifying capacity than CNC.Both HPMC and tannin could form a synergistic effect with nanocellulose,thus improving the stability of Pickering emulsion.Moreover,tannin successfully inhibited the excessive lipid oxidation of the emulsion.Besides,Pickering emulsions could contribute to reducing the rate of free fatty acid release.