Development and Validation of a Mathematical Model for HTST Processing of Foods Containing Large Particles

Abstract

A mathematical treatment for a heat penetration phenomenon with variable boundary conditions is presented. The system of differential equations for determining the unsteady-state temperature distribution inside a particle was solved by use of spectral methods as a new tool in food process development. A preliminary study was conducted on the use of a mathematical model to predict lethality in a sterilizing process. The model was validated using a calibrated time-temperature integrator (TTI) with immobilized Bacillus stearothermophilus spores, commonly used in TTIs for process validation. A comparison between the experimental data using Bacillus stearothermophilus and the predicted data obtained with the proposed model showed good agreement.

Kinetic Parameters for Thermal Degradation of Green Asparagus Texture by Unsteady‐state Method

“…where h fp is the convective coefficient between the fluid and the asparagus (W/m 2 ؒ؇C), Tf is the fluid temperature (؇C), n is the normal and Ts is the asparagus surface temperature (؇C). A spectral method was used to solve the heat equation (Mateu, 1997;Mateu et al, 1997). The spectral method presents an exponential convergence of the temperature function for regular geometries, is easily computed, and is adaptable to irregular geometries.…”

Kinetics of chemical marker M-1 formation in whey protein gels for developing sterilization processes based on dielectric heating

“…These problems prompted the development of time-temperature integrators as alternative process evaluation tools Kim, Taub, Choi, & Prakash, 1996). Several biological integrators have been reported in the literature (Holdsworth, 1992;Mateu, Chinesta, Ocia, Garcia, & Martinez, 1997;Pflug, Jones, & Blanchett, 1980;Pflug, 1982;Rodriguez & Teixeira, 1988). Those integrators were used to indicate the relative safety of food products, but not for locating coldspots.…”

Homogenized thermal conduction model for particulate foods

“…The microbiological information concerning the lethality in the coldest point, the integrated lethality and the number of microorganisms can be obtained according to the procedure described in [11,12] that we summarize in the following paragraphs.…”