Bacterial contamination is a significant problem for ethanol producers, because the bacteria compete with the yeast for sugar and nutrients and produce organic acids that can stress or kill the yeast as well as outbreaks can cause signifi¬cant losses in the yield of the ethanol plant, or even halt the fermentation process. Antibiotics have been used to control bacterial infections during fermentation in ethanol production for many years. Now chemicals and commercial compounds also used for bacterial contamination control in distillery factories The present study focused on tried several antibiotics i.e penicillin, tetracycline, virginamycin, erythromycin, cefadroxil, amoxicillin and amoxicillin+ flucloxacillin (1:1). Chemicals such as potassium meta bisulfite and chlorine, commercial preparations like KAMORAN®, Effymoll+ and DuPont™ FermaSure® XL. Culture condition such as effect of yeast strain, inoculum yeast format, inoculum size and pH were also studied. Promising results were obtained led to an performance in ethanol from 5.8-8.9% v/v consequently fermentation efficiency.
