A CAJM article on the nutritional and medicinal values of the baobab fruit (Adansonia digitata) of Southern Rhodesia (now Zimbabwe.)In the course of investigating the nutritional value of indigenous foods of Southern Rhodesia, the pulp of the baobab fruit (Adansonia digitata Linn.) was found to contain comparatively high concentrations of ascorbic acid (Carr, 1955). Similar results were obtained by B. M. Nicol (1957) in Northern Nigeria, although the ripe fruit appears heavier and the moisture content higher than the Rhodesian specimens.
In view of the encouragingly high quantities of vitamin C determined in a few samples, further investigations were undertaken to see whether any correlation could be found between size, degree of ripeness and moisture content with the ascorbic acid content and also the stability of the vitamin under different conditions

Carr, W.R.

Central African Journal of Medicine

English

In the course of investigating the nutritional value of indigenous foods of Southern Rhodesia, the pulp of the baobab fruit (Adansonia digitata Linn.) was found to contain comparatively high concentrations of ascorbic acid (Carr, 1955). Similar results were obtained by B. M. Nicol (1957) in Northern Nigeria, although the ripe fruit appears heavier and the moisture content higher than the Rhodesian specimens.

In view of the encouragingly high quantities of vitamin C determined in a few samples, further investigations were undertaken to see whether any correlation could be found between size, degree of ripeness and moisture content with the ascorbic acid content and also the stability of the vitamin under different conditions

Carr,  W.R.

National Research Database of Zimbabwe

The Baobab Tree: A Good Source of Ascorbic Acid

IDS OpenDocs

Vol. 4. No. 9. O j\t T  E i\T
ORIGINAJL A R T IC L E S
Cardiac Disease of Obscure Origin M. G e l ja n d ...............................365
Baobab Tree as a Source of Vitamin (' W. R. C a r r ............................... 372
Assessment of Muscular Hypertrophy and Endar­
teritis Obliterans in Pulmonary Arteries j\ J B a rn a rd ..........................375
Portal Hypertension R. mines Walker - - 378
Artificial Heart D. H. Thompson 381
Acute Poliomyelitis in Europeans J, M e lv in ................................... 385
First School of Medicine in Southern Africa (,, B. da G raca ..........................391
Diabetes Mellitus J. C. Shee -  392
The Untimely Demise of Dr. John Crotchett I. A nderson ................................394
E D IT O R IA L S
Children in H osp ita l................................395
Hepatic C ir r h o s is .....................................390
Diphtheria in the African - - - - 390
State Lotteries Grants for Doctors - - 397
Session in S.R. Parliament - - 398
Opening of New Childrens’ Home,
S a lisb u ry .............................................. 399
Opening of New Mpilo African Hospital 401
Meeting of Orthopaedic Association - 402
Dr. Samuel L ip tz .......................................... 403
In Rhodesia T h e n .....................................404
Book Reviews - - - - - - - - -  405
The Journal Library.....................................408
Salisbury Clinical C lub................................409
Latest Pharmaceuticals - - - - -  4 m
PUBLISHED MONTHLY, ANNUAL SUBSCRIPTION £2 2s. Od.
Registered at the General Post Office as a Newspaper.
September, 1958
The Baobab Tree: A Good Source of Ascorbic Acid
BY
W. R. CARR
Food Technologist, Nutrition Council, Salisbury.
In the course of investigating the nutritional 
value of indigenous foods of Southern Rhodesia, 
the pulp of the baobab fruit (Adansonia digitata 
Linn.) was found to contain comparatively high 
concentrations of ascorbic acid (Carr, 1955). 
Similar results were obtained by B. M. Nicol 
(1957) in Northern Nigeria, although the ripe 
fruit appears heavier and the moisture content 
higher than the Rhodesian specimens.
In view of the encouragingly high quantities 
of vitamin C determined in a few samples, further 
investigations were undertaken to see whether 
any correlation could be found between size, 
degree of ripeness and moisture content with the 
ascorbic acid content and also the stability of 
the vitamin under different conditions.
I. 'Habit and Habitat of A. digitata in 
Southern Rhodesia
The baobab tree grows in most areas of South­
ern Rhodesia which lie below about 3,000 feet, 
but is perhaps most widespread in the Sabi and 
Limpopo valleys. The trees come into leaf and 
flower in September, and the pods ripen in early 
May and often stay upon the trees until the 
advent of the next rainy season. In fact, samples 
of a previous year’s crop have been taken in the 
following March. Unless deliberate attempts 
are made to harvest the crop, some pods will 
remain on the trees for up to a year, although 
most will fall in June and July. It is obvious, 
therefore, that the stability of the pulp ascorbic 
acid is of some importance.
II. Common Names and Uses of A. digitata
The baobab is known by a multitude of names. 
Watt and Breyer-Brandwijk (1932) and Wild’s 
dictionary (1952) give a number of them. In 
English it may be known as the monkey bread 
tree, cream-of-tartar tree or lemonade tree, and 
in Afrikaans as Krimmetatboom. The following 
African names are widely used: muBuyu (Man- 
vika, Lozi, Shangaan), muGuya (Kalanga), 
umKomo (Ndbele), muUyu (Shona), muWiyu 
(Zezezuru).
Watt and Breyer-Brandwijk state that the 
fruit has been used in making an acidulous 
drink for fever cases and also used as a dysen­
tery remedy. The leaf has been used as a
Page Three Hundred and Seventy-Two
diaphoretic and a prophylactic against fevers to 
check useless perspiration and as an astringent. 
The bark has been used as a substitute for 
cinchona bark under the name “ Cortex cael 
cedra.”
M. Gelfand (1957), in his book on David 
Livingstone, observes that the missionary treated 
indolent sores with a poultice made from 
powdered baobab leaf, and he considers that the 
ulcers may well have been of dietetic origin.
In Nyasaland, Jessie Williamson (1955) states 
that the pulp may be used as a substitute for 
cream of tartar in baking powders, the seeds 
may be roasted and used instead of groundnuts 
to add to side dishes, and that the scraped seeds 
and pulp make a “ milk”  if pounded and boiled 
with water. She also states that the leaves are 
eaten cooked with potash.
Nicol (1957) says that the Hausa-speaking 
Natives in Nigeria make soup from the leaves, 
and the emulsion prepared by mixing the pulp 
with water is used to dilute the thick guinea 
corn dough to a thin gruel. A milk and baobab 
fruit juice mixture is a popular drink with the 
Hausa farmer.
In S. Rhodesia a drink is commonly prepared 
from the pulp mixed with water, and this emul­
sion is often mixed with maize or millet meal 
to give a thin gruel similar to the Nigerian 
practice. The seeds are sucked to remove the 
pulp, and amongst the Shangaans in the southern 
low veld it is a common sight to see large quan­
tities of washed seeds lying in the sun to dry, 
after which they are roasted and ground to 
produce a product like peanut butter (dowi).
The leaf is cooked with cooking soda (or the 
traditional soda prepared from burnt mealie or 
millet stems) to produce a mucilaginous side 
dish known by the generic name of derrere, 
but this practice is not very widely carried out. 
Generally speaking, most Africans living in "the 
low veld will collect baobab pods to suck the 
seeds or make a drink from the pulp, but 
amongst the Shangaans and Batonga more effort 
will be taken to utilise the seed and pulp in 
different ways. Other uses include the stripping 
of the bark to use as rope and string, and in 
areas of the Zambesi valley where baobabs are 
rather scarce, this has resulted in the death or 
partial death of many trees.
III. Analysis 
(a) Methods Used
The methods used were the same as those 
described in a previous communication (Carr, 
1955). The majority of ascorbic acid assays
T h e  C en tr a l  A f r ic a n
Jo u rn al  of M e d ic in e
T h e  C en tr a l  A f r ic a n
Jo u r n a l  of M e d ic in eSeptember, 1958 THE BAOBAB TREE AS A SOURCE OF VITAMIN C,
were carried out by the 2: 6-dichlorophenolindo- 
phenol method, with occasional checks with the 
osazone method. It was noted that the former 
method invariably gave about 5 per cent, higher 
figures than the latter, suggesting that a small 
amount of interfering substances was present. 
However, all the figures given are those obtained 
with the former method, i.e., reduced ascorbic 
acid. The moisture content was obtained by 
heating the sample for four hours at 100° C.
(b) Results
(i) Sample of Fresh Young Leaf.—
Ascorbic acid content: 85.5 mg./lOO g. 
Moisture content: 74.5 per cent.
No reduced ascorbic acid could be detected 
in a relish prepared from the leaves.
(ii) Unripe Pods.— The samples were taken 
at the Sabi Experiment Station in early March. 
Immediate analysis of the wet pulp showed 
moistures in the order of 80 per cent, and no 
ascorbic acid. The pods were allowed to stand 
on the bench for a fortnight and pods from 
seven different trees gave figures from nil to 
111.7 mg./lOO g. ascorbic acid (11 samples), 
with moistures ranging from 64.6 per cent, to 
76.2 per cent. Generally the lower the moisture 
the higher was the ascorbic acid content. 
Further “ drying out”  trials were inconclusive, 
as the pods became very mouldy on keeping. 
Seventy-five per cent, is approximately the limit­
ing moisture content for the presence of ascorbic 
acid.
(iii) Ripe Pods.— Eight pods from one 
medium-small-sized tree at the Nyanyadzi Irri­
gation Scheme in the Sabi Valley were selected 
in 1956 to decide whether any association be­
tween size of pod, moisture content and ascorbic 
acid content existed. No relationship between 
these variables could be detected.
Mean. Max. Min.
Weight of whole fruit ... 59.5 g. 88 g. 33 g.
Ascorbic acid (mg./lOO
g.) of pulp ............. 309.6 394.8 240.4
Moisture of pulp -............. 10.5% 10.9% 10.2%
These samples were stored one month in the
laboratory before testing.
Further tests in 1957 were carried out on 20
pods from three more trees in the same area.
Mean. Max. Min.
Weight of whole fruit ... 173.2 g. 252 g. 119 g.
Ascorbic acid (mg./lOO
g.) of pulp ............. 361.3 422 302
Moisture of pulp ............. 12.1% 14.9% 11.4%
Mean per cent, seed in whole fruit: 34.9%
Mean per cent, pulp in whole fruit: 14.3%
There was again no relation between weight, 
ascorbic acid content and moisture content, hut 
it is interesting to note that all three are higher 
than the previous year’s figures. Nicol (1957) 
in Nigeria found a mean weight for six pods 
of 462 g., mean moisture content of 20.8 per cent, 
and mean ascorbic acid content of 373 m g,/ 
100 g. (range 302-445 mg./lOO g.).
The Nigerian fruit weighs nearly three times 
that of the Rhodesian, although a very large 
range of sizes can be found in Rhodesia; how­
ever, the author has seen no local pods which 
approach the Nigerian weight. The moisture 
content of the pulp is also considerably higher, 
but the ascorbic acid content remains much in 
the same order.
(iv) Keeping Trials and Stability of Ascorbic 
Acid.— Pulp from fruit collected at the Sabi 
Experiment Station was kept on - the bench in 
clear glass bottles for six months, in the form 
of a fine powder. The bottles were exposed for 
part of the day to direct sunlight. The pulp 
from fruit from each of 10 different trees was
Table I
Comparison- of A scorbic A cid and Moisture Contents of the Pulp from Pods 
Stored for Six Months with the Bulked Pulp from Pods Collected
from the Same Tree
Tree No. 3 Tree No. 9 Tree No. 10
Bulked pulp moisture, 6/7/55 ................................ 10.0% 11.4% 10.0%
Stored Pod: Pulp moisture, 4/1/56 ....................... 14.5% • 15.3% 14.5%
Per cent, increase in moisture ............. 45% 34% 45%
Bulked pulp ascorbic acid content, 6/7/55 ............. 399 mg./lOO g. 433 mg./lOO g. 175 mg./lOO g.
Stored pod pulp ascorbic acid content, 4/1/56 ... 264 mg./100 g. 340 mg./lOO g. 144 mg./lOO g.
Per cent, loss of ascorbic acid ...................... 31.3% 21.5% 17.9%'
Page Three Hundred and Seventy-Three
T hf. C en tr a l  A fric a n
Jo u rn al  of M e d ic in e
September, less the baobab tree as a source Of vitamin c
bulked, giving 10 samples, which were re-assayed 
for ascorbic- acid. The following figures were
obtained:—■
Mean ascorbic acid content
of fresh pulp ............. 306 mg./lOO g.
After six months’ storage ...  276 mg./lOO g.
Mean loss of ascorbic acid ...  9.9%
Maximum loss of ascorbic acid 14.1% 
Minimum loss of ascorbic acid 6.4%
After a further eight months’ storage one 
sample was exposed to direct sunlight and air 
for seven weeks in a thin layer with frequent 
turning. The pulp turned from a cream to a 
brownish-pink colour, and the following figures 
were obtained:—
mg./100 g. %  Loss
Ascorbic acid content of fresh pulp 295 . —
After six months ................................  264 10.7
After 14 months plus seven weeks
of sunlight ................................  161 45.5
In the same series three pods from three 
different trees were stored on the bench for six 
months. In this case only the trends can be 
examined, as there is almost as much variation 
between individual pods from the same tree as 
between pods from different trees. The results 
are expressed in Table I. Appreciably greater 
losses in ascorbic acid content than in the case 
of the bottled pulp seemed to be related to 
increased moisture content, which was probably 
due to the higher humidity occurring in Janu­
ary. This was further borne out when two 
samples of the previous season’s crop were taken 
in March, i.e., the ripe fruit had remained on 
the tree for approximately 10 months. The 
ascorbic acid and moisture contents of the pulp 
were 65 mg./lOO g. (moisture 20.1 per cent.) 
and 50 mg./lOO g. (moisture 19.2 per cent.). 
Notwithstanding these losses, a considerable 
amount of ascorbic acid was present in the pods.
Plumtree School herbarium kindly donated 
a pod that was at least five years old. The pulp 
had turned a brown colour, but was easily re­
duced to a fine powder. The intense pigmenta­
tion made it difficult to obtain a result in the 
2: 6-dichlorophenolindophenol method for ascor­
bic acid, but there was a great deal of difference 
between this and the result obtained in the 
osazone method. However, the following results 
were obtained:—
Weight of whole fruit ....................... 90 g.
Pulp moisture content ....................... 12.9%
Ascorbic acid content (iridophenol
method) ..........................................  ±15 mg./lOO g.
Ascorbic acid content (osazone
method) ..........................................  68 mg./lOO g.
Per cent, seeds ' ................................  37.7%
Page Three Hundred and Seventy-Four
Per cent, pulp ................................  - 8.9%
It appears, therefore, that some ascorbic acid 
will remain after many years’ storage.
Summary and Conclusions
No correlation between moisture, weight and 
ascorbic acid content of the pulp of normal ripe 
baobab fruit could be detected, but the unripe 
fruit does not show any ascorbic acid content 
until the moisture of the pulp drops below 75 
per cent.
An average ripe pulp will have an ascorbic 
acid content of about 350 mg./lOO g., which 
will remain remarkably stable for many months 
if protected from increased moisture content. 
Even if no precautions are taken, appreciable 
quantities of the vitamin will remain in the 
pulp for many years. The pulp showed no signs 
of bacterial or fungal decomposition after two 
years’ storage in a glass bottle.
Some seasonal difference in the ascorbic acid 
content of the pulp was detected, but it appeared 
to be small.
The baobab leaf was also shown to be a good 
source of ascorbic acid, but a relish prepared 
from the leaves showed no reduced ascorbic 
acid; however, no assay for dehydroascorbic 
acid was undertaken, and the presence of cook­
ing soda may have produced this form of the 
vitamin. Obviously the baobab is an important 
antiscorbutic for the low veld African, and is 
undoubtedly an important factor in the com­
paratively low incidence of scurvy in these areas. 
It is made more valuable in the way it can be 
regarded as a storehouse of the vitamin due to 
the remarkable stability of the vitamin in the 
pulp.
REFERENCES
Carr, W. R.' (1955). Nature, 176, 1273.
Gelfand, M. (1957). Livingstone, the Doctor. Basil 
Blackwell, Oxford.
Nicol, B. M. (1957). Nature, 180, 287.
W att, J. M. & Breyer-Brandwijk, M. G. (1932). The 
Medicinal and Poisonous Plants of Southern Africa. 
E. & S. Livingstone, Edinburgh.
W ild, H. (1953). A Southern Rhodesian Botanical 
Dictionary of Native and English Plant Names. Gov­
ernment Printer, Salisbury.
W illiamson, Jessie (1955). Useful Plants of Nyasa- 
land. Government Printer, Zomba.
A cknowledgment
I wish to thank Dr. D. M, Blair, o.b.e., Direc­
tor of Medical' Services (Southern Rhodesia), 
for permission to undertake this research and to 
publish the findings.
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The Baobab Tree: A Good Source of Ascorbic Acid

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