Food safety is always a concern for food manufacturers. During aseptic processing, food is sterilized or pasteurized in a tubular heat exchanger, helical heat exchanger, scraped-surface heat exchanger or microwave/ohmic heater. The packaging is sterilized in an aseptic packaging machine and both food and packaging are brought together during the filling operation. The aseptic process has significant quality advantages over the classical thermal techniques such as batch (canning) and semi-batch operations.

Flow modeling is being used as an analysis tool to ensure that food products meet the safety requirements of FDA regulations and HACCP guidelines. For example, flow modeling results can help determine the optimal lengths of the heating, holding and cooling sections in a tubular heat exchanger.

Results from simulation of flow and heat transfer in a helical heat exchanger show the asymmetric velocity distribution at the outlet. Flow modeling can be used to quantify the amount of mixing that occurs, the detailed temperature history of the fluid and the overall heat transfer rate.

In this example, flow modeling results for the temperature profile in a lab-scale tubular aseptic processing system are compared with experimental measurements with excellent agreement. Courtesy of North Carolina State University