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The need for formulating a production schedule in a make-and-fill plant with a large number of final products and limited number of preparation and storage tanks is a very common problem in the food industry. Through the best possible assignment of tanks to products and optimal production scheduling, it is possible to minimize wait times and idle process times and, therefore, the total production makespan. In this setup, the major decisions involve the committment of tanks to products and scheduling of production orders. Overall, this problem can be considered as belonging to the general category of Tank Farm Management or Tank Farm Operation Problems (TFOP). The problem was formulated as a Mixed-Integer Linear Programming (MILP) mathematical model and solved through MATLAB. Taking into account constraints that arise from the production process and quality control, different objective functions were formulated and the relevant optimal solutions were generated. Optimization criteria used were the minimization of total makespan, the minimization of the number of batches, the minimization of tank capacity used and combinations of the above. A plant producing dressings and condiments was used as a case study for the implementation of the mathematical model. Two production days were modeled and the results were compared with the actual production process used empirically in the plant; the actual production was modeled through the scheduling software SchedulePro®. It was concluded that the objective function that simultaneously minimizes the number of batches and the makespan, produces schedules which are very close to those empirically derived and implemented in the plant. The advantage of an optimal mathematical formulation is that it constitutes a scalable tool that can be used at any time to produce optimal schedules in a fast way and without the need toSummary 6 make complex mathematical calculations.It was proposed, as future work, to expand the model by incorporating labor availability and cost, introducing, in this way, financial criteria in addition to equipment usage criteria used in the current formulation.