This is an interesting result because gas produc-
tion experiments showed that CO2 production ceased after 7 days
(Figs. 5 and 6) and cultures were dormant for a long time before
starch breakdown commenced after 20 days incubation. When
the experiments were started with 10 ml yeast inoculum about
95% of total sugar and 70% protein were removed after a 25 day
incubation but yeast produced large amounts of CO2 only during
the first few days of the incubation (Figs. 5 and 6). CO2 gas produc-
tion was high after 2 or 3 days but then rapidly declined to zero
due to the rapid digestion of easily metabolized organic com-
pounds. Mobilization of starch only became apparent after more
than 20 days incubation but it was interesting that little or no
CO2 was produced as a result of this late mobilization of starch.
Glucose would have been the breakdown product of starch
hydrolysis by the a-glucoamylases but no significant amounts of
CO2 was being produced by conversion of pyruvic acid into alcohol
and CO2.