Hydrophobic‐assembled curcumin–porcine plasma protein complex affected by pH

Abstract

SummaryPorcine plasma protein (PPP) was used as encapsulation material based on its hydrophobic regulation through pH shifting, as follows: the exposed hydrophobic residues of PPP provide binding sites to curcumin at extreme alkaline pH value 12, and then, PPP–curcumin complex is formed by re‐adjusting the pH to a near neutral value. The stability and dispersibility of curcumin were significantly improved by this pH shifting method with PPP as carrier. The highest encapsulation efficiency (65.4%) of curcumin–PPP complex was obtained at 0.2 mg mL−1 curcumin concentration. The stability of curcumin–PPP complex improved with increasing ultimate pH value. The antioxidant activity of curcumin bound to the complex was comparable with that of native curcumin and did not get affected by heating at 121 °C for 1 min. Overall, a stable curcumin–PPP complex was formed by pH shifting method without organic solvents or specific equipment; this approach may considerably contribute to utilisation of PPP in the food industry.