Emulsification Properties of Plant and Milk Protein Concentrate Blends

Blending is a promising strategy during the partial replacement of plant with animal proteins. This, however, may lead to alteration in the technofunctional properties of the resultant blends. In this study, partial replacement of milk protein concentrate (MPC) with different plant proteins including soy, rice and pea protein concentrates (SPC, RPC and PPC, respectively) was conducted to determine the effect of blending at different ratios on the technofunctional properties relevant to their emulsification behavior, e.g., emulsion stability, viscosity and water holding capacity (WHC) and oil binding capacity (OBC). It was observed that at equivalent concentrations, the plant protein concentrates had higher apparent viscosities compared to MPC and the blends. RPC–MPC, at all ratios (25:75, 50:50, and 75:25), had a lower OBC when compared with the SPC–MPC and PPC–MPC blends. The lowest OBC was 32.5, for RCP–MPC 25:75, and the highest was 116.0 for SPC–MPC 25:75. The highest solubility of PPC, RPC, and SPC was observed in their blend form at 50:50 (73.2%), 75:25 (86.5%) and 25:75 (71.1%) ratios, respectively. Plant protein–MPC blends showed higher emulsion stability than the individual plant protein concentrates. The highest emulsion stability was 100%, for RPC–MPC 50:50 and 75:25 ratios, PPC–MPC at 50:50 ratio, and SPC–MPC at 25:75 and 100:0 ratios. Among the blends, SPC–MPC 25:75, PPC–MPC 50:50 and RPC–MPC 50:50 showed the most suitable overall emulsification properties. Based on the results, blending MPC with plant protein concentrates led to promising improvements in emulsification behavior relevant to different composite protein ingredient applications.