Particle size distributions of the whole milk powders after reconstitution in water determined by Matersizer (Malvern Instruments Ltd, Worcestershire, UK). Low-preheated (70 °C, no holding time) powders (A) and high-preheated (95 °C for 20 s) powders (B); homogenised at 4 MPa (●) and homogenised at 7 MPa bar (○). Confocal micrographs of reconstituted milk powder are also presented in figure with arrows. Arrows in the micrographs show aggregated particles in the samples. Confocal microscopy was performed as described by Ye et al. .