Pickering emulsion stabilised by double‐modified starch particles and its delivery property for curcumin

Abstract

Summary Rice starch was hydrophobised by octenyl succinic anhydride (OSA) and then modified by roast dry heating at 180°C for 40 min (RDH‐40) to improve its digestibility. The oil‐in‐water Pickering emulsions stabilised by double‐modified starch particles were fabricated. The emulsion stability under different formulation parameters was investigated. Results showed that the suitable parameters for fabrication of Pickering emulsion were RDH‐40 concentration of 4.0 wt.%, oil volume ratio of 50% and pH of the system was 7.0. The addition of NaCl and sucrose (0–200 mmol/L) slightly reduced the emulsion stability. Microstructure results revealed that the starch particles and a few gelatinized starch macromolecules distributed around the oil droplets, making the emulsion more stable. Compared with the emulsions stabilised by Tween 20 and OSA starch, the Pickering emulsion stabilised by 4.0% RDH‐40 starch showed the highest loading and embedding rates for curcumin at 25 and 40°C. The emulsion stabilised by RDH‐40 had a faster free fatty acid release rate and higher curcumin bioaccessibility than that stabilised by OSA starch during in vitro digestion. This study helps to develop new starch‐based Pickering emulsions for the delivery of oil‐soluble bioactive substances.