Impact of the whey protein/casein ratio on the reconstitution and flow properties of spray-dried dairy protein powders

This study focuses on the impact of whey protein/casein ratio (100/0, 79/21, 57/43, 35/65, and 12/88) physicochemical functional characteristics dairy protein powders. Spray-drying was performed in following conditions: 200 °C inlet air temperature 85 outlet temperature. Physicochemical properties (particle size distribution, shape factors, moisture content, water activity) spray-dried powders were characterized to explain their reconstitutability, basis wettability, dispersibility, solubility indices, flowability, evaluated with FT4 powder rheometer. Reconstitutability analyses revealed that linearly varied ratio. It also highlighted wettability dispersibility determined standard methods not relevant evaluate reconstitutability investigated powders: fact, all studied non-wettable non-dispersible according milk standards. likely result from low median particle (between 10 30 ?m) produced by spray-drying at pilot-scale. The flowability as poor due a high level interparticular cohesion, which mainly derived small size. composition statistically significant, despite modification reflected decrease sphericity upon casein proportion increase. size, leading flow properties, overwhelmed ratio, but slight improvement reduction cohesion induced higher proportions proteins.