Dairy powder breakage: Mechanisms, characterization methods, impacted properties and influencing factors

Background: Particle breakage deteriorates dairy powder properties and it easily takes place in many processes. However, there currently is a lack of research on dairy powder breakage for understanding and controlling it. The research on particle breakage in other industries is very extensive and thorough, and could act as good reference knowledge for dairy powder breakage research, but at this time there is no review of this useful information. Scope and approach: Based on the research done in dairy powder breakage and findings of particle breakage studies of other industries relevant to dairy powder particle properties, this review includes the breakage mechanisms of dairy powders, methods suitable for studying dairy powder breakage, the influence of breakage on powder properties, and influencing factors of dairy powder breakage which also can be considered as controlling factors. Key findings and conclusions: Powder breakage significantly affects dairy powder physical properties which in-turn influence powder functionalities, especially the rehydration properties. The extent of agglomerates breakage corresponds to different breakage mechanisms which result in different final particle sizes and particle size distributions. The processing conditions (such as the parameters during dry-mixing, vibration, and pneumatic conveying) and the characteristics of particles (including physical properties and composition) are two main influencing factors that can be considered to control dairy powder breakage. However, there is currently not enough study showing which factors are more effective in controlling breakage. Some single-particle or multi-particle tests can be used to investigate dairy powder breakage and further research on the effectiveness of those controlling factors should be done.