Abstract: A new technique for alcohol production from cassava powder was developed using microwave treatment followed by Rhizopus arrhizus fermentation to substitute the traditional steaming process. The optimal conditions for alcohol production from a mixture of cassava powder pretreated in this way and water at a ratio of 1:2 were determined by the orthogonal array design method to be 55-min saccharification at 60 ℃ and pH 5.0 with the addition of 120 U/g glucoamylase followed by 72-h fermentation at 30 ℃ with the addition of 0.1% active dry yeast. Under these conditions, the alcohol content of fermentation broth was 16.0%, which was increased by 13.5% compared with the traditional liquefaction by means of steaming. Moreover, the new process could save the energy consumption by 42.81%.

Key words: microwave, microorganism, cassava, alcohol, fermentation