Dec. 27,191$ Carbohydrate Transformations in Sweet Potatoes 
549 
reducing sugar, cane sugar, and starch in the half of the potato analyzed 
at the beginning, and the corresponding half analyzed at the end of the 
same period. These differences therefore represent the increments in the 
percentage of these substances in the stored halves during the 10- or 12- 
day storage period. 
In the discussion of these tables it will be most convenient to compare 
the results of the experiments conducted at 30° with those of the experi¬ 
ments conducted at 5 0 and to consider later the experiments at 15.5 0 C. 
The first and second experiments carried out at 30° (Table III) are 
similar in plan and execution and the results are entirely congruous, so 
that they may be discussed together. In both of these experiments 
there is a marked loss of starch during the first period of 12 days following 
the digging of the potatoes, but very little further loss during the second 
period. The changes in cane sugar correspond inversely to the changes 
in starch. During the first period there is a large increase in cane sugar, 
but during the second period there is almost no further gain. The 
figures showing the changes in reducing sugar during the first period are 
irregular, but during the second period there is a consistent and well- 
marked loss. 
Table III. —Changes in composition of sweet potatoes at 30° C. 
first experiment (first period) 
No. of 
sweet 
potato. 
4a. . 
4b. . 
5 a.. 
5b. . 
6a. . 
6b. . 
7a. . 
7b. . 
8a. . 
8b. . 
9 a.. 
9 b. . 
Moisture. 
Reducing 
sugar as 
glucose. 
Difference. 
Cane sugar. 
Difference. 
Starch. 
Difference. 
Per cent. 
Per cent. 
Per cent. 
Per cent. 
74. 02 
0. 47 
} o -37 
/ 2. 6 3 
} i -95 
f 18. 9 I 
} “ 3 - 3 3 
68. 63 
.84 
l +58 
l I 5 * 59 
73 - 11 
70. 41 
• 79 
1. 02 
} -23 
J 2 - 3 « 
\ 4- 06 
| 1.68 
J 19- 44 
\ 17.02 
} “ 2 - 4 2 
73 - 73 
66. 38 
• 9 1 
. 65 
) — . 26 
f 2. og 
X 4 • 52 
} 2 - 43 
r i 9 . 16 
\ 16.11 
} “ 3 - 05 
73 - 9 i 
65* 7 i 
. 80 
• 74 
) — . 06 
f 2. 22 
l 4- 85 
} 2 - 6 3 
r 18.88 
l 15- 6 2 
} “3- *6 
73. 12 
6g. 70 
. 81 
•93 
} 
/ 2. 52 
1 3-82 
} i- 3 ° 
J 19- 36 
l 17* 43 
} - r -93 
74. 06 
• 93 
} “ - 3 2 
r 1.81 
} 2 - 74 
r 18.66 
} “ 3 -06 
65. 26 
. 61 
l 4*55 
l . 15-60 
FIRST EXPERIMENT (SECOND PERIOD) 
I3a. . . 
I3b. . . 
71.10 
64.10 
1. 41 
• 52 
| -0.89 
J 3- 62 
l 4 - IS 
} 0 - 53 
f 18.84 
l 18.97 
} +°- 13 
I4a. . . 
72. 52 
i* 23 
} -'74 
J 3 -61 
} 
/ r 7 - 93 
} “ -37 
I4b . . . 
66. 50 
-49 
l 4 - 48 
l i 7 - 5<5 
I 5 a. • • 
7 i* 58 
1. 21 
) — . 81 
f 3.86 
} • 79 
f 18. 23 
} - 09 
I5b. . . 
65. 01 
.40 
l 4 - 6S 
\ 18. 14 
20a. . . 
74 - 15 
i- 38 
} - • 7 2 
/ 3 - 79 
} • 74 
/ 15 - 6 3 
} . + • 33 
20b . . . 
66. 14 
. 66 
i 4 - S 3 
l is- 96 
21a.. . 
72 . 57 
1.24 
) - .81 
/ 4 . OO 
} .88 
J i 7 - 49 
} -- 5 * 
21b. .. 
63- 55 
•43 
\ 4-88 
l 16- 97 
23a.. • 
73-25 
1.44 
J- - .86 
/ 3 - 36 
) .08 
/ 17 - °5 
} • 75 
23b. .. 
66.78 
.58 
l 3-44 
\ 17.80 
