In this work, we investigated some factors affecting
ethanol production from molasses. The important factors
were found to be the invertase activity of yeast and
inhibitors of yeast invertase existing in molasses. A laboratory
strain, X2180-lB, could not ferment well in a
high concentration of molasses because its invertase activity
was low and it was inhibited by inhibitors present in
the molasses to a level of almost zero. Thus, one of the
characteristics required in a yeast to be used for high ethanol
production from molasses is strong enough invertase
activity to overcome the inhibition. The invertase of
the alcohol yeast YOY655 remained active and hydrolyzed
sufficient amounts of sucrose, even under the inhib