A STUDY OF SWEET POTATO VARIETIES. 
tion of attractive and desirable canned goods of very great impor- 
tance. 
The investigations reported upon in this paper were made possible 
by the presence at the Arlington Experimental Farm, where this 
work was done, of variety test plats, where upward of 40 varieties 
^ and strains of sweet potatoes have been under study for a number of 
years. J. H. Beattie and C. J. Hunn, of the Office of Horticultural 
and Pomological Investigations, Bureau of Plant Industry, have 
these varieties under observation, furnished much of the raw material, 
and otherwise facilitated the work. No claim is made that all 
varieties are embraced in this study, but all those generally con- 
sidered as important are included. There has been much confusion 
in the variety names of sweet potatoes, and it is hoped that the 
studies now in progress in the Office of Horticultural and Pomo- 
logical Investigations will make clear the relationship of the numer- 
J ous strains. 
It is possible that under different climatic and soil conditions the 
same varieties might have given slightly different results from those 
here reported. Comparative canning tests upon potatoes from other 
sections of the country have not been made, though these would have 
been of interest. The potatoes used were handled under carefully 
controlled conditions, and the uniform treatment which they received 
makes possible a direct comparison of the merits of the different 
varieties. This has been the object of the work, and it is believed 
that the information presented will be found of service not only to 
those interested in the canning of this product but also to those fol- 
lowing other methods of sweet-potato utilization. 
\ CHEMICAL COMPOSITION OF SWEET POTATOES. 
In entering upon a study of this sort it is necessary to know some- 
thing of the chemical composition of the material under consideration. 
Table 1, taken from the work of Atwater and Bryant (i), 1 shows 
the chemical composition of both the fresh sweet potato and the 
canned product. 
Table 1. 
-Chemical composition and calorific value of fresh and of canned 
sweet potatoes. 
Constituents (per cent). 
Condition. 
Water. 
Protein. 
Fat. 
Total 
carbo- 
hydrate 
(includ- 
ing fiber). 
Fiber. 
Ash. 
Fuel 
value per 
pound 
(calories). 
Fresh, raw 
69.0 
55.2 
1.8 
1.9 
0.7 
.4 
27.4 
41.4 
1.3 
.8 
1.1 
1.1 
570 
Canned 
820 
1 Serial numbers in parentheses (Italic) refer to " Literature cited " at the end of this 
bulletin. 
