Chapter 9 - Time–Temperature Superposition Principle and its Application to Biopolymer and Food Rheology

Abstract

The time–temperature superposition principle (TTSP) is mostly used to describe the viscoelastic behavior of polymers at short and long observation times or frequencies. The rheological data (creep, oscillatory, or stress sweep) at selected temperature can be superposed into a master curve at an arbitrary reference temperature by employing temperature-dependent horizontal and vertical shift factors. Although TTSP has been used for many decades, no strict rules have been developed for obtaining the master curves. Construction of master curve with rheological data is demonstrated in this chapter, and furthermore, application of the principle to food and biopolymers have been discussed. Since the concept has been developed for homopolymers at temperature above the glass transition, the applicability of TTSP has a limited scope for a complex system like food and biopolymers. The failure of application of TTSP to biopolymer dispersions could be attributed to structural changes in the aggregates resulting from temperature changes that in turn affected the chain mobility on which the rates of all configurational rearrangements depend.