Establishing Thermal Processes for Heterogeneous Foods to be Processed Aseptically: A Theoretical Comparison of Process Development Methods

A mathematical model for predicting heat transfer into particulate foods processed in a continuous aseptic system was developed. Various approaches were taken to theoretically design thermal processes for a commercially sterile model product. The impact of the thermal treatment on possible nutrient retention and on accumulated microbial effectiveness was assessed. Comparison of the approaches presented indicated that neglecting the thermal contribution of a heat exchanger while scheduling the thermal process for a particle center F o of 6.0 min could result in an effective F o of as high as 78 min. In addition, such a conservative approach can result in higher nutrient destruction, 13.6% to 18.6%, instead of 6% to 17% depending on particle size.