AriRL 1, 1903.J THE TROPICAL AGEICULTURIST. 
663 
EXPEKIMENT3 AT ANTIGUA, 
At the time when the question of conveitiug sweet 
potatoes into meal came into piomiQence owing to the 
necessities of Anguilla, Mr. Francis Watts, the 
Government Chemist for the Leeward Islands, 
obtained information from Spoouer of Bendals' 
estate in Antigna, concerning some experiments 
which he had previously carried out in this direction. 
Mr. Spooner's attention was drawn to the subject 
in 1898, when sweet potatoes were exceptionally 
abundant. The rpain points in Mr. Spooner's method 
were as follows : — 
The cleaned potatoes were cut into slices, about 1/16 
of an inch in thickness. The cutting was at first 
done by hand but later an old chaff cutter, temporarily 
adapted to the purpose, was employed with very 
good results. The slices were spread out on gal- 
vanised wire netting and quickly dried in the sun, 
until quite brittle. This state was reached in six or 
eight hours, when conditions were favourable. They 
were then stored in old flour barrels until sufficient 
had accumulated to be worth grinding, for which 
an engine on the estate was utilized. 
The yield of meal by this method was 40"63 per 
cent, of the original weight of the potatoes ; one ton 
of roots yielding 910 lb. of meal. Mr. Spooner esti- 
mated the cost at £i. 9. 7. per ton of meal, that is 
to say approximately ^d. per pound. Several tons of 
meal were made and used with great success for 
feeding mules and stock. The labourers ate it readily, 
and Mr. Spooner says that he personally found it a 
palatable and satisfactory form of food. It kept 
well, provided the slices had been thoroughly dried 
before being ground, but losses were incurred when 
for any reason, the slices were left at all leathery 
instead of being perfectly brittle. The meal made 
from such leathery slices quickly became tainted and 
spoiled. It is important to note how by the use of 
simple machinery the cost was reduced to such a 
low figure as Jd. per pound. The preparation was 
analysed by Dr. Voelcker who reported : ' The meal is 
well dried containing only 12 per cent, of water 
and should keep perfectly well. It contains practi- 
cally 10 per cent, of sugar, with 67 per cent, of 
starch and digestible carbohydrates, 5 per cent, of 
nitrogenous or protein matters with a not inconsider- 
able portion of mineral (bone-producing) matter. 
The percentage of indigestible (woody) fibre is very 
email. 
Dr, Voelcker's complete analysis is as follows : — 
per cent. 
Moisture .. .. 11-99 
Nitrogenous matter* ... 6'12 
Oil ., .. 1'19 
Sugar ... .. ... 9"90 
Starch and digestible oarbohydratea 67 01 
Indigestible (woody) fibre .. I'89 
Mineral matter (ashy) f .. .. 2'90 
* Containing nitrogen 0'82. 
•f Including sand, 0'03. 
The comparatively high percentage of nitrogenous 
matter in this sample is noteworthy. This is the 
element which is lacking in the dietary of many of 
the West Indian natives, and of which so large a 
proportion was lost by the Anguilla mode of 
manufacture. From the above facts it will be seen 
that it is possible to produce from the sweet potato 
a meal which is palatable, digestible and cheap. It 
is essential that the potato should be quickly and 
thoroughly dried and then reduced to meal. By this 
treatment the greatest amount of nutritive material 
is retained. For such a locality as Anguilla it is 
important to determine whether a meal can be made 
at crop time and stored for use during the period 
of drought. To this end it is essential to know ; 
(1) The food value of sweet potato meal, and (2) its 
keeping qualities, 
roOD VALtlE. 
In a perfect diet the ratio of the albuminoids or 
nitrogenous matter to the digestible carbohydrates 
and sugar together should be about 1 : IJ. This re- 
lation is spoken of as the ' nutrient ratio.' The 
above analyses of sweet potato meal show that its 
nutrient ratio is low. The first sample of Anguilla 
meal gave a ratio of 1 : 24, and in the later samples 
it was even less. In the Antigua meal the ratio 
was much higher, about 1 : 15, Iq an analysis of 
fresh sweet potatoes, recorded by Prof. Church in hia 
book on Food the ratio is given as 1 :13. Speci- 
mens of a Barbados variety analysed by Professor 
d' Albuquerque gave as low a ratio as 1 : 50. This 
deficiency of the mfal in proteid matter can easily 
be counterbalanced by supplementing it with such a 
food substance as pigeon-peas, which are rich in 
nitrogenous constituents, in common with the seeds 
of many other leguminous plants. In pigeon- 
peas the nutrient ratio is about 1:3. As has 
already been stated these peas are grown in 
Anguilla, in sufficient amount in fact to be an article 
of export. They are one of the staple foods during 
the dry season. Taken alone however they are not 
beneficial, containing too large a percentage of pro- 
teids in proportion to their carbohydrate and sugary 
contents. In conjunction with sweet potato meal 
they would make a good diet, capable of sustaining 
the inhabitants during the season of scarcity, 
KEEPING QUALITIES. 
Some of the meal prepared by Dr. Rat was sent 
to the Head Office of the Department at Barbados, 
in tins, and after about twelve months' ordinary 
storage was perfectly sweet and good. Mr. Spooner a 
testimony as to its keeping powers has already been 
given. There appears therefore to be no doubt that 
the meal, carefully prepared, will keep good for 
several months — a sufficient time to serve the im- 
mediate purpose of the people of Anguilla, 
EXPERIMENTS IN PR0GKES3. 
In June of the present year (1901) the Depart- 
ment obtained for use in Anguilla a grinding mill 
and a vegetable slicer. During the coming crop 
season these will be tried, and it is hoped that an 
impetus will be given to the establishment of a 
regular industry in sweet potato meal, the importance 
of which to people situated as are the inhabitants of 
Anguilla, it is difficult to over-estimate. 
OTHER USES OP SWEET POTATOES 
Another method of preservation, namely, canning 
sweet potatoes has been tried on an industrial scale 
in America. Mr. Diiggar says o{p. cit, p. 25 ' With- 
in recent years sweet potatoes have been canned in 
a few localities. In 1893 a factory in Mississippi 
canned about 1.000 bushels using three-pound cans 
which sold in Chicago at 95 cents per dozen deli- 
vered. A bUshel of sweet potatoes was sufficient for 
fifteen cans. Farmers were paid 40 cents a bushel. 
This firm expected to can about 8,000 bushels of 
sweet potatoes in 1894.' Suchja method whilst of in- 
terest is hardly likely to be of practical importance 
under present West Indian conditions. Besides fur- 
nishing an important porti ni cf man's diet, in many 
warm countries, sweet po .itoes are very useful as 
fodder for cattle ai d stock. Both roots and vines 
(foliage^ may be employed to this end. Mr, Dnggar, 
in the pamphlet already referred to, compares the 
relative food-values of corn and sweet potatoes. His 
results are expressed as follows ; — 
lidntivc Food Value of Corn and Stccet Potatoes. 
a 
i! a § ^ 
►.S "3 - 
o a & ^ 
Qd o ^ S a 
* z 2 
lb. lb. lb. 
100 lb. Corn contain . , 89 1 lO-.S 75 
300 ibi Sweet potatoes coutaiu S6,7 4*5 75'3 
