Evaluating The Applicability Of Time Temperature Integrators As Process Exploration And Validation Tools

Knowledge of the impact of thermal processing in the food industry is crucial in order to deliver high quality safe foods to the consumer. Time Temperature Integrators (TTIs) have been developed as quality control and process exploration tools for processes where use of other thermal sensors is impossible. TTIs are encapsulated enzymatic suspensions with well characterized thermal inactivation kinetics, whose activity can be measured easily before and after processing. From the reduction of the TTI activity it is possible to estimate the inactivation of pathogens and spoilage organisms, as well as nutrients in the product. Although TTIs are currently used in many industries a thorough review of their applicability to evaluate thermal processes has not yet been published. Here, experimental validation of an α-amylase TTI is shown with the intention of accurately characterising the variability of the technique. In an attempt to describe the thermal variability of real food processes the heat and mass transport in typical food processes where TTIs might be used were simulated using CFD. Monte Carlo simulations to study the effect of (i) process variability and (ii) the measurement variability inherent within TTI response. Results indicate that TTIs can be used both to validate thermal processes; and as a process exploration tool. In the latter form, they can be used to derive information about variation, although a larger number of TTIs would be required.