Rheological properties of selected dairy products.

This article reviews rheological properties of milk, concentrated milk, cream, butter, ice cream, and yogurt, as well as the structure and some physicochemical properties of milk components. A brief description of basic rheological concepts related to liquids, solids, and viscoelasticity is presented, including those rheological models commonly used to characterize dairy products. Rheological behaviors exhibited by these dairy products, including Newtonian in milk and concentrated milk, nonNewtonian in concentrated milk, cream, and yogurt, thixotropy revealed by concentrated milk, cream, and yogurt, and the viscoelastic characteristics displayed by butter, ice cream, and yogurt, are analyzed, and relevant process variables affecting the rheological behavior of dairy products are discussed. Also, to facilitate the comparison of test methods and identify the typical instrumentation and models utilized in rheological characterization of dairy products, experimental conditions and equations used for modeling are included in a tabulated form.