Abstract: A multi-objective optimisation model was applied to decide the best alternative for the proper design of heat exchangers for continuous sterilisation process of fluid foods. A vector of objective functions that includes a capital cost function and a mathematical expression for quality deterioration was considered. For a comparative analysis, the model using four different single objective functions was also simulated. The thermal time distribution pattern or Fo distribution was incorporated into an external optimisation loop, which finally gives the optimum values for a given set of design and operating variables (tube radius, tube length, external temperature). The partial differential equation model was solved by finite difference method, whereas the optimisation program makes use of the goal attainment algorithm or Pareto optimisation. This last optimisation method is well suited to establish an operable range within which the user must finally decide. The proposed optimisation model was illustrated by simulating the process with several typical fluid foods and the optimum results obtained were discussed when multi-objective functions were applied.
Purlis Emmanuel and Segura Juan , 2004. Multi-objective Optimisation of Continuous Sterilisation Processes . Journal of Food Technology, 2: 326-330.