Enzyme effects
The effects of enzyme addition and sterilization in
green and overripe bananas (whole fruit) are shown
in Fig. 2. The green bananas yielded poorly without
the addition of enzymes. Actually there was a 65.4%
difference between the standard process and the
process without the enzymes. A large difference was
expected since the majority of the carbohydrate in
green bananas is in the form of starch. There was a
further decrease in ethanol yield with the no
enzyme/no sterilization treatment. The overripe
bananas in the no enzyme treatment did ferment,
but the yield was 13.4% lower than with the
standard process. Again, very little ethanol was produced
from the overripe bananas with the no
enzyme/no sterilization process. A foul smell was
produced when fermenting the overripe bananas,
which indicated the growth of spoilage microorganisms.
These results show that enzyme addition can
result in signihcant improvement in the ethanol yield
of both