Different light-scattering techniques (integrated and dynamic) were used to study the overall distribution of particle sizes in milk homogenized using a microfluidization technique. This demonstrated that only integrated light scattering was able to show clearly that a population of small fat droplets, with radii less than 100 nm, was produced during the homogenization, This population of small particles had not previously been detected, nor were they clearly demonstrated using dynamic light scattering, but their presence was confirmed by physical separation using centrifugation and study of the separated fractions by light scattering, The presence of these particles may require revision of the methods used to determine size distributions in homogenized systems. It will also affect the analyses of adsorbed layers of protein in emulsions and of the kinetics of particle aggregation in emulsions which are undergoing destabilization.