17 
0.17 per cent; solids in the juice, G.89 per cent; total hydrolyzable 
carbohydrates, expressed as invert sugar, 5.80 per cent ; reducing 
sugars, as invert sugar, 3.29 per cent; sucrose, 1.72 per cent; and 
total sugars, 5.01 per cent. 
The point of special interest in these data is the small percentage 
of sugars in the green fruit. It should be borne in mind in this con- 
nection that the above data were secured from fully grown fruit 
which, so far as could be judged, were just at the beginning of the 
ripening process. In addition, these analyses were made by the use 
of the fruit itself, rather than the juice. While the reducing sugars 
and sucrose make up a small percentage of total sugars the hydro- 
lyzable carbohydrates, which were determined by boiling samples 
of the fruit with hydrochloric acid, show that the storage of reserve 
material in the growing pineapple is slight, and if severed from the 
plant at this stage it can not possibly develop a normal sugar con- 
tent in subsequent ripening. Pineapples gathered green and allowed 
to ripen afterwards were found to have the following average com- 
position: Acidity, 0.58 per cent; fiber, 0.22 per cent; solids in the 
juice, 6.45 per cent; reducing sugars, 1.22 per cent; sucrose, 3.90 
per cent; total sugars, 4.12 per cent; and total hydrolyzable carbo- 
hydrates, as invert sugar, 4.35 per cent. 
The principal changes that take place in this process are the con- 
version of reducing sugars into sucrose, and a slight increase in 
acidity. There is a pronounced development of flavor and a general 
softening of the tissues, but the true fiber is not materially changed. 
The average composition, when approximately one-fourth ripe, was 
found to be as follows: Acidity, 0.65 per cent; solids in the juice, 
8.68 per cent; reducing sugars, 2.74 per cent; sucrose, 4.42 per cent; 
total sugars, 7.16 per cent; and when half ripe the fruit contains: 
Acidity, 0.65 per cent; reducing sugars, 2.97 per cent; sucrose, 6.74 
per cent ; and total sugars, 9.71 per cent. When allowed to ripen nor- 
mally on the plant, the composition was found to be as follows: 
Acidity, 0.74 per cent; reducing sugars, 4.23 per cent; sucrose, 7.88 
per cent ; and total sugars, 12.11 per cent 
The composition at the several stages of ripening shows that there 
is a rapid accumulation of sugars, especially sucrose, and a slight in- 
crease in acidity during the development of the fruit. From a study 
of the physiology of this plant we can better understand the analytical 
data. It has been shown that the normal pineapple plant stores up 
large amounts of starch in the stalk and base of the leaves, whereas 
only faint traces of starch could be detected in any portion of the 
fruit at any stage of its development. The fruit stem was found to 
contain small quantities of starch ; also there are scattering granules 
in the cells immediately adjacent to the epidermis. These cells were 
[Bull. 28] 
