Evaluation of the integrated time‐temperature effect in thermal processing of foods

Abstract
In this review, current methods used to evaluate the integrated impact of time and temperature upon preserving a food product by a heat treatment are considered. After identifying the basic premise any preservation scheme shall meet, the central role of a feasible description for the heat activation kinetics of microorganisms, their spores, and other quality attributes are stressed. Common concepts to quantify a thermal process are presented. Shortcomings of the prevalent evaluation methods are highlighted and attention is given to the development, restrictions, and possibilities of time‐temperature‐integrators as “new” evaluation tools to measure the impact of a “classical” in‐pack heat treatment and more modern heating techniques such as continuous processing of solid/liquid mixtures on foods.