A theoretical procedure for using multiple response time-temperature integrators for the design and evaluation of thermal processes

Abstract

Time-temperature integrators (TTI) offer a sound alternative to in situ and physical-mathematical methods for thermal process design and evaluation. In the present work, the use of multi-component TTI systems, in cases where a single-component TTI with a particular z value is not available, was investigated. A procedure in using double or triple response TTI systems to evaluate the impact of a thermal process on a particular target heat labile substance was proposed and evaluated, based on a large number of product time-temperature profiles. Parameters to be considered in using a multi-component TTI included the z values of the TTI, in relation to the target z value, as well as the reference temperature used for the calculations. Guidelines for proper selection of the parameters involved are given. Although, generally, triple response TTIs performed better compared with double response TTIs, the results of double response TTIs were also satisfactory, and for practical applications, the use of a double response TTI might be sufficient.