| 摘要 |
The present invention addresses the problem of providing: a method for removing bacterial contaminants from a saccharified solution, whereby it becomes possible to prevent the proliferation of bacteria in a fermentation vessel without requiring the use of an antibiotic in the alcoholic fermentation of a biomass saccharified solution using the conventional yeast; and a fermentation system which is suitable for the implementation of the method for removing bacterial contaminants from a saccharified solution. In the bacterial contaminants removal method and the fermentation system according to the present invention, rough separation, which is a procedure for withdrawing a saccharified solution (a fermentation solution) out of a fermentation vessel and then collecting yeast from the saccharified solution, is carried out. Subsequently, fine separation, which is a procedure for removing the bacterial contaminants from the saccharified solution from which the yeast has been separated out, is carried out. In this manner, only the bacterial contaminants can be removed from the saccharified solution while collecting the yeast. The rough separation is performed by the membrane filtration using a filtration membrane having a pore size of 0.5 to 5 μm inclusive or the centrifugation at 50 to 500 G inclusive. The fine separation is performed by the membrane filtration using a filtration membrane having a pore size of 0.22 μm or less or the centrifugation at 1000 to 15000 G inclusive. |
