Mar. 6, 1917 
Fermentation of Corn Silage 
377 
suggested by investigators in plant physiology, who have often found 
zymase in plants, and is corroborated by the nature of the alcohol curves 
shown. The curves suggest a later production of alcohol by yeasts, 
and results from the other experimental silage support this idea. As 
stated above, Esten and Mason (6) found large numbers of yeasts in 
com silage. Both factors, therefore, probably have a share in the 
alcohol production. 
A similar statement holds good for the hydrolysis of protein as indi¬ 
cated by the amino-nitrogen content of the silage. Proteoclastic enzyms 
are present in com grain, 
and the curves show 
evidence of their activ¬ 
ity. Both the later rise 
in the amino-nitrogen 
curves noted above and 
the results from silage 
in which the enzyms 
were destroyed show 
some proteoclastic ac- ^ 
tivity by microorgan- © 
isms also. It is note- o 
worthy that E. J. Rus- S 
sell (17) found end pro- . 
ducts of protein hydro- g 
lysis in com silage made 
in the presence of tolu¬ 
ene, which hydrolysis 
he ascribed to enzym 
action. 
The evolution of car¬ 
bon dioxid must be due 
, . Fig. 12.— Curve showing the formation of alcohol in series 5* 
largely to enzym action. 
The curves shown all agree on that point, even when the first period 
was only 12 hours. Evidence that yeasts produce a part of the carbon 
dioxid after the first day has also been pointed out. 
The rise in temperature of the silage is not great except at the surface, 
where the material is in contact with air. Microorganisms seem to be 
responsible for most of the heating, but the partial influence of enzyms is 
not excluded. 
SUMMARY 
The question of the 'respective causal relationship of microorganisms 
and plant cell enzyms to the fermentation of com silage has long been 
in controversy. It is difficult to differentiate between the activities of 
these two kinds of agents. Work with antiseptics both by earlier investi¬ 
gators and by the writer is not conclusive. Experimental silage, other 
DAYS 
