Development of Food‐Grade Curcumin Nanoemulsion and its Potential Application to Food Beverage System: Antioxidant Property and In Vitro Digestion

Abstract Curcumin nanoemulsions (Cur‐NEs) were developed with various surfactant concentrations by using high pressure homogenization and finally applied to the commercial milk system. Characterization of Cur‐NEs was performed by measuring the droplet size and polydispersity index value at different Tween 20 concentrations. The morphology of the Cur‐NEs was observed by confocal laser scanning microscopy and transmission electron microscopy. Antioxidant activity and in vitro digestion ability were tested using 2,2‐diphenyl‐1‐picrylhydrazyl, 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) diammonium salt, pH‐stat method, and thiobarbituric acid reactive substances assays. Cur‐NEs were found to be physically stable for 1 mo at room temperature. The surfactant concentration affects particle formation and droplet size. The mean droplet size decreased from 122 to 90 nm when surfactant concentration increased 3 times. Cur‐NEs had shown an effective oxygen scavenging activity. Cur‐NEs‐fortified milk showed significantly lower lipid oxidation than control (unfortified) milk and milk containing curcumin‐free nanoemulsions. These properties make Cur‐NEs suitable systems for the beverage industry.