The macroscopic rheologic properties of networks formed by lipids are of extreme importance in food products that contain significant amounts of fats. Such products include butter, margarine, chocolate, peanut butter, ice cream, and many spreads such as cream cheese. Many of the sensory attributes such as
spreadability, mouthfeel, snap, and texture are dependent on the mechanical strength of the underlying fat crystal network. However, it must not be inferred from this that knowledge of the mechanical properties of the fat network provides complete knowledge of the food product within which it is formed. In addition to this obvious industrial importance, fat crystal networks form a particular class of soft materials, which demonstrate a yield stress and viscoelastic properties, rendering these materials plastic. From a materials sciences point of view, the rheological behavior of these materials is also extremely important.