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Pasteurization of canned apple puree was simulated for a 3-D geometry in a semi-rigid aluminum based container which was heated from all sides at 378 K. The computational fluid dynamics code Ansys Fluent 14.0 was used and the governing equations for energy, momentum, and continuity were computed using a finite volume method. The food model was assumed to have temperature-dependent properties. To validate the simulation, the apple puree was pasteurized in a water cascading retort. The effect of the mesh structures was studied for the temperature profiles during thermal processing. The experimental temperature in the slowest heating zone in the container was compared with the temperature predicted by the model and the difference was not significant. The study also investigated the impact of head space (water-vapor) on heat transfer.

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Commercial application of infrared (IR) heat has been hampered by a lack of readily available data adaptable to high‐throughput (HT) drying requirements in the grain processing industry. This study evaluated the effectiveness of a continuous flow IR heating system to simultaneously dry and decontaminate corn over various drying bed thicknesses (1.5, 2.7, and 4.5 cm). Additionally, impacts of intermediate tempering treatment and variation of IR emitter angle (zero [E‐0] and 30 [E‐30] degrees) on drying and decontamination of the corn were determined. Although IR heating was able to dry and decontaminate corn at the initial moisture content (MC) of ≈21% wet basis (w.b.), moisture removal was most effective at the least bed thickness (1.5 cm). At 1.5 cm bed thickness, a safe storage MC (<14%) was achieved after 15 min of IR heating. At all the bed thicknesses, IR heating with intermediate tempering resulted in higher fungal inactivation than IR heating without tempering. Infrared heating of corn at 1.5 cm bed thickness plus tempering resulted in a total fungal count (TFC) reduction of 3.1 and 4.6 log CFU/g using IR emitters at E‐30 and E‐0° angles, respectively. However, increasing the bed thickness to 2.7 cm resulted in a TFC reduction of 4.8 and 4.6 log CFU/g using E‐30 and E‐0, respectively. Infrared heating using E‐0, compared to using E‐30, accelerated TFC reduction when corn samples were dried at 1.5 cm bed thickness. These results could help guide the design of HT corn drying and decontamination systems.