A properly executed production scheduling brings great advantages to a company, that’s why this work aims to develop the same for a lactose company and its main production line liquid 1 (fermented, jellies and juices), which is characterized by being a flexible Flow Shop with sequence dependent setup times, in order to minimize the number of late jobs. To achieve this objective, a software was created, which allows to find a proper production order. Relied on the method of Lot Streaming, where an equation was created in order to find the proper amount of sublots to achieve the desired production programming. A software base on a genetic algorithm heuristic was developed, this algorithm was composed by five stages that were developed according to methodologies found in the literature review. (random initialization, ranking selection method, Two-point (ver I)crossover, Shift mutation, criteria for iterations without improvement finalization). In each of the aforementioned stages, there is a repair process, which evaluates the infactibles chromosomes and turns them into workable solutions. The implementation and analysis of the application had several instances given by the Company that compared with the results obtained by the software. With the foregoing, the comparison of the application against two dispatch rules was made, a static SPT (shortest processing time) and a dynamic CR (critical ratio), the results showed that the software always had a greater impact in terms of the reduction of late jobs and makespan.