Fabrication of pea protein-curcumin nanocomplexes via microfluidization for improved solubility, nano-dispersibility and heat stability of curcumin: Insight on interaction mechanisms

Poor dispersibility of curcumin (cur) in aqueous medium and heat instability are common drawbacks preventing its efficiently practical use. Herein, the aim of this work was to reduce the size of cur crystals to the nanoscale through solid dispersion technique and subsequently stabilize them in an amorphous form. In this work, different ratios of pea protein (PP) to cur (6: 1, 12:1, 18:1 and 24:1, w/w) nano-supernatant (NS) in water were prepared via microfluidization. Results showed that particle size, Zeta potential (ZP) and cur concentration of cur in PP-cur NS in optimal conditions reached 357.45 nm, −33.43 mV and 81.68 mg/L, respectively. PP-cur NS showed excellent storage stability within one month and high heat stability of 52.32% at 90 °C after 180 min. Structural analysis including FT-IR, DSC and XRD indicated that cur entered into the hydrophobic pocket of PP by hydrophobic interactions and hydrogen bonds after microfluidization. This study indicated that PP exhibiting as an emulsifier and carrier might significantly reduce the surface tension of NS and in turns prolong their storability.