Brazilian sugar cane spirit (cachaça) production is traditional among rural producers in Santo Antônio da Patrulha-RS-Brazil. In this work, in similar conditions used by the producers, the effect of different °Brix and nutrients concentration on sugar cane juice fermentation time and ethanol yield was tested. Sixteen experiments were executed, predicted in a statistical planning, in order to identify the effect of eight factors. The results indicate that the increase on manganese sulfate

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... ration and cornmeal amount, and also the zinc sulfate concentration increase in interaction effect with higher °Brix, cause increase in fermentation time. It was also observed that the ethanol yield was higher at lower °Brix and at higher triple superphosphate amount in interaction effect with higher °Brix. Ammonium sulfate and copper sulfate concentrations, and also rice bran amount had no significant influence on the process. The best parameters determined, at local conditions, to obtain the lowest fermentation time and higher ethanol yield are the following: 14°Brix, triple superphosphate 0.5 g/L, zinc sulfate 0.5 g/L, manganese sulfate 0.2 g/L, cornmeal 5 g/L. It is also indicated the maintenance of ammonium sulfate 0.5 g/L and rice bran 5 g/L.