26 
BULLETIN 859, U. S. DEPARTMENT OE AGRICULTURE. 
fruit ripened without wrapping. The acid content of fruit ripened 
without ventilation shows an increase of approximately 138 per cent 
over that of vine-ripened fruit; that of fruit ripened while wrapped 
with one paper, an increase of approximately 102 per cent; and that 
of fruit ripened while wrapped with three papers, an increase of about 
58 per cent. The soluble carbohydrate content for fruit ripened 
without ventilation shows a decrease of nearly 21 per cent compared 
with normal fruit; that of fruit ripened while wrapped with one 
paper, a decrease of nearly 5 per cent; and that of fruit ripened 
while wrapped with three papers, a decrease of nearly 6 per cent. 
The data presented also bring out the fact that green tomatoes 
ripened when exposed to air and unwrapped are superior in taste 
and chemical composition to the same fruit ripened when wrapped 
with paper. 
Several experiments were carried out in order to determine what 
effect lack of ventilation produced on the normal color of the tomato. 
Since they all yielded the same results, it will suffice to present the 
figures from one. Two large glass jars were filled with green fruit 
and cardboard covers placed over each. Unwrapped fruits were 
placed in baskets as checks. Both lots were held at room tempera- 
ture and examined at the same time. (Table VIII.) 
Table VIII. — Effect of lack of ventilation on the normal coloring of tomatoes held at 
room temperature. 
21 fruits in bottles 
(no ventilation). 
31 fruits in baskets (ventilated). 
Time of examination. 
Green. 
Turning. 
Green. 
Colored. 
Turning. 
Pink. 
Red. 
Total. 
21 
6 
10 
6 
5 
9 
a 26 
25 
After 12 days 
21 
31 
a 14 SOft. 
These results would seem to indicate that lack of ventilation 
retards ripening and the consequent formation of pigment in the 
tomato. It was noticed that the tomatoes kept in jars were firmer 
than those left exposed to the air. Hill (24) records a similar 
condition in the case of peaches held in an atmosphere of carbon 
dioxid (C0 2 ). His explanation is that C0 2 evidently prevents the 
hydrolysis of the pectin to which peaches owe their hardness. This 
may also be the case with tomatoes. An attempt was made to 
duplicate the results presented above by using a larger closed chamber 
and also by wrapping the fruit in paper, but no concordant data 
were obtained. There are hardly sufficient data to justify making 
any statement as to the effect of wrapping on the color formation. 
It is often noticed that tomatoes picked green and ripened arti- 
