Rheological Testing for Semisolid Foods: Traditional Rheometry

Abstract

A review of the literature on the rheology of semisolid foods such as yogurt, reveals significant challenges in acquiring data which adequately reflects the material characteristics of the food. These challenges are due to a number of factors, including the disruption of the structure of the semisolid food during loading on rheology test equipment, the instability of many semisolid foods over time, and the tendency of many semisolid foods to exhibit macroscopic phase separation. Due to these challenges, empirical testing methods are often used instead of fundamental rheology tests, which limits comparison of data. Despite these inherent difficulties, reliable and useful rheology data can be collected on these types of foods if appropriate techniques are used. This data can provide critical information about the food structure, texture, and processing behavior and in some cases can be used to develop predictive models which enable food formulators to more rapidly design semisolid foods with desired behaviors.