The preparation of plant-based milk substitutes with antioxidant properties using soybean protein isolate and curcumin composite nanoparticles

作者：Du, Chenxing; Wang, Zijun; Zheng, Zhi^*

来源：Food Science and Technology, 2023, 182: 114780.

DOI：10.1016/j.lwt.2023.114780

• Plant-based milk substitutes
• Nanoemulsion
• Soybean protein isolate
• Oxidative stability
• In vitro digestion

This study produced a nanoemulsion with antioxidant properties using soybean protein isolate-curcumin nanoparticles (SPI-Cur-NPs) as a plant-based milk substitute. The relevant properties of the nanoemulsions were investigated by characterizing the particle size, polydispersity index (PDI), & zeta;-potential, and loading capacity. Confocal laser scanning microscopy and transmission electron microscopy verified that the emulsion was the O/W type and that the droplet size was approximately 70 nm. After treatment with 63 degrees C, pH (2.0, 4.5, 9.0), and various concentrations of NaCl at 0, 200, and 500 mM, the nanoemulsions containing 4% SPI-Cur-NPs were stable and homogeneous. Due to the presence of curcumin, thiobarbituric acid-reactive substances were maintained at a level approximately 3.2-fold lower than the control during the 14-day accelerated oxidation experiment, while the peroxide value of this nanoemulsion was maintained at approximately 0.0184 & mu;mol/L during the 30-day storage experiment. Experiments on in vitro digestion revealed that the lipid release rate in the nanoemulsion exceeded 80%, significantly greater than the free state of 27.8%. Hence, nanoemulsions stabilized by SPI-Cur-NPs can be considered a potential plant-based milk substitute that can supplement fat-soluble nutrients and has excellent stability.