Consecutive pH adjustment and direct steam injection modifies the functional properties of milk protein concentrate 70 and nonfat dry milk powder

Background, Context or Rationale Currently, research has been conducted to improve the functionality of milk protein concentrate (MPCs) powders, but no research has been performed to check the combined effect of direct steam injection (DSI) and pH change on the functionality of MPCs. Aim Therefore, this study aimed to investigate the effect of DSI processing, along with pH change, on the functionality and compositional properties of dried MPC70 (M70) and nonfat dry milk (M34) powders. Two temperatures (85°C and 105°C) and three pH values (7, 8 and 9) were studied. The control samples of each powder type were produced with no DSI and pH treatment. Methods The samples were evaluated for chemical composition, total and soluble protein profile, zeta potential (ζ‐potential), hydrodynamic diameter, functionality (solubility, foaming capacity and stability, apparent viscosity, heat stability and rennet gelation time) and microstructure. Major Findings Mean values of solubility and ζ‐potential showed a significant increase for M70 samples treated with increased pH treatment at both evaluated temperatures as compared to control samples. The ζ‐potential values of M70 samples treated at pH 9 and evaluated at 85°C and 105°C were −39 and −41 mV, respectively. The solubility values of M70 samples treated at pH 9 and evaluated at 85°C and 105°C were 99.838% and 99.848%, respectively. The viscosity values of M70 samples treated at pH 9 and evaluated at 85°C and 105°C were 1.45 and 1.55 mPa.s, respectively. A decrease in the mean values was observed for the hydrodynamic diameter of M70 treated with increased pH at both evaluated temperatures. The opposite effect was observed in M34 samples treated with increased pH at both evaluated temperatures. Industry Implications This research provides the industry with a new technique to enhance the functionalities of the MPCs. This can potentially help expand the food applications for MPCs.