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Energy and nutrient contents of “waterfufu and eru”.

  • University of Buea & Research Foundation Tropical Diseases and Environment, Buea, Cameroon


Because of persistent reports of malnutrition in some parts of Cameroon, a popular Cameroonian food, “waterfufu and eru” was analyzed for its energy value and nutrient content in order to determine to what extent it satisfies recommended dietary allowances (RDA). Results showed that average serving size of the dish was 409 g. This amount provided 601 kcal of energy, 281 g of moisture, 82 g of carbohydrate, 30 g of lipids, 11 g of protein and 5 g of ash on fresh weight basis. Micronutrients were found to be 1402 mg iron and 123 mg zinc. After due adjustment for absorption and bioavailability and considering the one serving size, constituted one of a three meal/day regime, although there was no significant difference (P > 0.05), lipid, zinc and iron contents of the dish satisfied RDAs of all groups of consumers while energy value, carbohydrate and protein contents did not. This suggested that dependence of communities on this diet for supply of their daily needs may partly be responsible for the reported prevalence of malnutrition in these areas. It was suggested the food be improved upon through fortification and/or supplementation with the necessary elements.
African Journal of Food Science. pp. 016-019, October, 2007
Available online
ISSN 1996-0794 ©2007 Academic Journal
Full Length Research Paper
Energy and nutrient contents of “waterfufu and eru”
Abia W. A.
, Numfor F. A
, Wanji S.
and Tcheuntue F.
Biochemistry Programme, Department of Biochemistry and Microbiology, Faculty of Science, University of Buea.
Institute of Agricultural Research for Development (IRAD) Ekona, BP 25, SWP Cameroon.
Accepted 3 September, 2007
Because of persistent reports of malnutrition in some parts of Cameroon, a popular Cameroonian food,
“waterfufu and eru” was analyzed for its energy value and nutrient content in order to determine to
what extent it satisfies recommended dietary allowances (RDA). Results showed that average serving
size of the dish was 409 g. This amount provided 601 kcal of energy, 281 g of moisture, 82 g of
carbohydrate, 30 g of lipids, 11 g of protein and 5 g of ash on fresh weight basis. Micronutrients were
found to be 1402 mg iron and 123 mg zinc. After due adjustment for absorption and bioavailability and
considering the one serving size, constituted one of a three meal/day regime, although there was no
significant difference (P > 0.05), lipid, zinc and iron contents of the dish satisfied RDAs of all groups of
consumers while energy value, carbohydrate and protein contents did not. This suggested that
dependence of communities on this diet for supply of their daily needs may partly be responsible for
the reported prevalence of malnutrition in these areas. It was suggested the food be improved upon
through fortification and/or supplementation with the necessary elements.
Key words: Malnutrition, Cameroon, “waterfufu and eru”, RDAs.
“Waterfufu and eru” is a traditional dish popularly eaten in
Cameroon and neighbouring Nigeria. It is made up es-
sentially of a cooked cassava (Manihot esculenta Crantz)
dough (“waterfufu”) and a vegetable soup (“eru”) whose
major component is “eru” (Gnetum africanum Welw)
leaves. The two components of the dish are prepared
separately but served together (Abia, 2003).
Previously the dish was associated with a particular
tribe (the Banyangs) as it was their staple meal. But in
recent years, almost all ethnic groupings, especially
those from the South West and North West Provinces
have learned to cook and eat “waterfufu and eru”. Its
popularity has spread to attain national dimensions
(Ewane, 2001).
The dish forms a regular part of the menu in many
households, parties, occassions and local restaurants,
particularly in the forest zones of Cameroon. The social,
cultural and economic value of eru cannot be overstated
(Ewane, 2001; Abia, 2003). In addition, ‘eru’ is one of the
commonest vegetables eaten in Cameroon today (Ewa-
ne, 2001). In some communities, it is not uncommon that
the dish constitutes the three meals of the day in some
*Corresponding author. E-mail:
households (Abia, 2003). Because of the popularity and
high frequency of consumption of the dish in some parts
of the country, there is a need to know what contribution
it makes to the well being of its consumers especially as
malnutrition continues to be reported in these areas
(Numfor and Noubi, 1995; Horemans and Jallow, 1997;
IFRC, 2007). Malnutrition affects every 1 in 5 children in
Cameroon, and was reported to have increased by 5.9%
from 1991 (15.1%) to 1998 (21.0%), contrary to the
country’s 1991 goal; to reduce malnutrition by 50% by the
year 2000 (UNICEF, 2002; ANB-BIA, 2002). More recent-
ly, according to IFRC, (2007), the prevalence of malnutri-
tion for the under fives stands at 27% and is most likely to
increase. Horemans and Jallow (1997), documented that
there are nutritional imbalances or deficiencies (in ener-
gy, protein and iron) particularly in the forest regions of
Cameroon. Similarly, Ifeyironwa (2000), reported high
level of anemia due to iron deficiency in Cameroon. Des-
pite the apparent and reported malnutrition in the South
West Province of Cameroon (Horemans and Jallow,
1997), no study has been documented on the impact of
the popular diet waterfufu and eru” on the nutrition and
health of its consumer population. Therefore, this paper
reports the nutritive value of the dish and within estimated
limits of absorption, the extent to which it satisfy the re-
commended daily energy and nutrient requirements of
Abia et al. 017
Table 1A. Percentage contribution of “waterfufu and eru” to RDAs of children (7-10 years) and P- values.
Issue Lipid (g) Protein(g) Carbohydrates (g) Zinc (mg) Iron (mg) Energy Value (Kcal)
25.8 9.6 69.8 6.2 70.1 511.4
53.0 34.0 309.0 10.0 23.0 1900.0
48.7 28.2 22.6 62.0 304.8 26.9
0.4400 0.7863 0.5363 0.1995 - 0.7275
three categories of its consumers namely children 7 - 10
years, adult females 19 - 50 years and adult males 19 -
50 years.
The research was carried out in the South West Province of
Cameroon based not only on the apparent and the reported mal-
nutrition in the province (Horemans and Jallow, 1997) but also due
to the high dependence on the diet, “waterfufu and eru” (Abia,
Food samples were purchased randomly from amongst some
previously surveyed restaurants in 5 communities (Limbe, Tiko,
Buea, Muyuka and Kumba) in the province, labeled and carried to
the Chemistry Analytical laboratory of the Institute of Agricultural
Research for Development (IRAD), Ekona Regional Centre, Buea,
South West Province Cameroon where the average normal serving
seize was determined and the samples processed for subsequent
The analyses included determination of moisture content by
drying samples in a draught oven at 105
C until a constant weight
was obtained. On dry weight basis, Lipid content was obtained by
hexane extraction using soxhlet apparatus and later concentrated
using rotavapour and allowed overnight for complete evaporation of
the solvent, after which weight was taken.
Total nitrogen content was determined using an adapted colo-
rimetric method of the analytical chemistry laboratory of IRAD,
Ekona, Buea (modified AOAC, 1990): 0.03 g of re-dried samples
placed in to separate 100 ml tecator tubes, followed by addi-
tion of a quarter fraction of kjeldahl tablet, 6 drops of distilled water,
and 2 ml of concentrated sulphuric acid. The contents of the tubes
were swirled gently for a few seconds to mix. The tubes were then
arranged in a rack and the rack was placed in a Tecator Block
Digestor (maintained in a fume cupboard) and its temperature
raised gradually to 370
C and let to digest for 70 min after which the
digest was let to cool in the fume hood. Thereafter, 50 ml of distilled
water was added into each tube, swirled gently, its content made up
to the 100 ml mark with distilled water, re-swirled gently and allow-
ed to stand overnight for colorimetric determination of nitrogen. For
colorimetric determination of nitrogen, 1 ml of each sample digest
was pipetted into a fresh test tube and added 6 ml of buffer solution
(50 g of sodium potassium tartrate and 26.8 g of di-sodium hydro-
gen phosphate was dissolved in distilled water. 54 g of sodium
hydroxide was dissolved in the above and made up to the 1000 ml
mark of the volumetric flask with distilled water), 4 ml of sodium
nitroprusside-sodium salicylate (150 g of sodium salicylate and 0.3
g of sodium nitroprusside were dissolved in distilled water and
made up to mark of a 1000 ml volumetric flask), and 1 ml of sodium
hypochloride solution or bleach solution (3 ml of commercial hypo-
chlorite solution (10 - 12% Cl) was diluted in distilled water to 100
ml). These tubes were shaken to mix and allowed to stand at
ambient temperature for 45 min for complete colour development to
occur. Thereafter absorbance was read at 650 nm and the percent-
tage nitrogen calculated as: Nitrogen (%) = Standard Factor (F) x
The standard factor (F = 12.081) is a value calculated from
the amount of dry sample used and the volumes of the standards
used for colorimetric determination. Hence the total protein (%) was
obtained by multiplying total nitrogen (%) by 6.25 (standard convert-
ing factor from nitrogen (%) to protein (%),
Total carbohydrate (and fibre) content of the dish was determined
by difference (subtracting the sum total of lipid, protein and ash
from total dry matter content), meanwhile ash content was deter-
mined by incineration in a muffle furnace at 550
C for 4 h, allowed
to cool and weight taken. The micronutrient contents analyzed
included zinc, and iron, which are currently a major concern in
Cameroon and the developing world in general (Barbara,
2000; MI
and UNICEF, 2004; Hotz and Brown, 2004), both using atomic
absorption spectrophotometer (AAS).
Considering that due to anti-nutritional factors as well as body
stores of each of the nutrient, not all the amount of the food
consumed may be assimilated, assimilability of each nutrient in the
diet, “waterfufu and eru” was estimated based on the dietary
components (Latham, 1997). They were then compared with the
Food and Agriculture Organization (FAO)’s recommended dietary
allowances (RDAs) (Latham, 1997) of children 7 - 10 years, adult
females 19 - 50 years and adult males 19 - 50 years (by multiplying
the ratio of each nutrient content to its corresponding RDA by 100,
so as to express the adequacy of each nutrient as a percentage of
RDA it provides, and further statistically concluding whether the
contribution made to RDA is significantly different from the require-
ment or not), after which some necessary recommendations were
The “waterfufu” component of the dish which is a product
of a starchy staple cassava tubers, is undoubtably the
major source of carbohydrates, while the eru” soup -
which is a combination of shredded dark green eru lea-
ves and other ingredients (pepper, red palm oil, crayfish,
magi and cowskin mainly), is the ultimate source of lipid,
protein and the minerals zinc and iron. Considering that
eru (Gnetum) leaves, a dark green leafy vegetable, forms
about 85% of the quantity of “eru” soup, it is most proba-
bly responsible for the rich micronutrient and even protein
contents of the soup (
Grivetti and Ogle, 2000).
Table 1A, 1B and 1C respectively), present -within the
estimated limits of assimilability- the extent (percentage)
to which nutrient contents in the whole diet contribute to
to which nutrient contents in the whole diet contribute to
the recommended daily energy and nutrient requirements
of major consumer categories (children 7 - 10 years,
adult females and males 19 - 50 years), as well as their
p-values. On the basis that “waterfufu and eru” form one
of three meals per day in the forest regions of Cameroon
a one third contribution or more ( 33.33%) of a nutrient a
018 Afr. J. Food Sci.
Table 1B. Percentage contribution of “waterfufu and eru” to RDAs of adult females (19-50 years) and P-values.
Issue Lipid (g) Protein (g) Carbohydrates (g) Zinc (mg) Iron (mg) Energy Value (Kcal)
25.8 9.6 69.8 6.2 70.1 511.4
62.0 49.0 359.0 12.0 48.0 2210.0
41.6 19.6 19.4 51.7 146.0 23.1
0.6596 0.4109 0.4030 0.3650 - 0.5960
Table 1C. Percentage contribution of “waterfufu and eru” to RDAs of adult males (19 - 50 years) and P-values
Issue Lipid (g) Protein (g) Carbohydrates (g) Zinc (mg) Iron (mg) Energy Value (Kcal)
25.8 9.6 69.8 6.2 70.1 511.4
81.0 55.0 470.0 15.0 23.0 2895.0
31.9 17.5 14.9 41.3 304.8 17.7
0.9519 0.3301 0.2405 0.6702 - 0.3375
to its recommended daily allowances was considered
satisfactory or adequate.
Hence lipid, zinc and iron contents of the diet were
observed to be in adequate amounts as each satisfies
more than one third of their respective nutritional needs
of the major consumer groups, while protein, energy and
carbohydrate did not provide up to one-third of the RDAs
of any of the considered population. However, no statis-
tical difference (P > 0.05) was observed in either case.
Although failure to satisfy the recommended dietary allo-
wances does not in every case mean deficiency, however
it is an indication of the likely hood and that the further
contributed amount of any nutrient is below the RDA of a
target category, thus deficiency is most likely.
A fundamental strategy to ensure the well-being of a
community with frequently reported malnutrition is the
food-based approach which involve finding out the role of
popular foods on the nutrition and health of its consum-
ers. This was done by assessing the energy value and
nutrient contents of a popular food (“waterfufu and eru”)
in Cameroon, whose communities in the forest zones in
particular, highly depend upon. Thereafter, estimated
assailable nutrient amounts were compared with the
RDAs of major categories of consumers, and necessary
conclusions and recommendations made.
The observed energy value and nutrient contents of the
“waterfufu and eru” were obvious based on earlier reports
on their respective raw material contents: cassava and
green leafy vegetables (Bokanga et al., 1990; Oshidi,
1992; Mialoundama, 1993; Numfor and Noubi, 1995;
Ejoh et al., 1996; Okafor et al., 1996; Chavez et al., 2000;
Grivetti and Ogle, 2000; Danso et al., 2001, Sango,
2007). Furthermore, it corroborates with the report of
Abia, (2003), who reported that eru leaves in eru soup
generally contributes at least 60% of each of the nutrients
in the soup. Thus the whole diet, “waterfufu and eru”, is
balanced in terms of the various nutrients. Its energy
value and nutrient content can be constituted into a food
value table amongst others and made to the awareness
of the public to probably appropriate diets of the popu-
However, with the knowledge that not all that is eaten is
bio-available, the nutrient contents were adjusted for
assimilability based on the dietary components: starchy
roots, vegetables and little -or in most cases no- animal
protein. Thus, assimilability factor of each macronutrient
(lipid, protein and carbohydrate) was similar to the factors
of Latham (1997), and that of the micronutrients (zinc and
iron) correlated with those of WHO, (1996) and Latham
(1997) respectively.
The comparison on table 1 provides relevant informa-
tion which probably serves as an indicator of the inade-
quacy of the diet and the risk of nutritional pathology
amongst individuals who depend predominantly on the
food. It reveals that, considering the diet as one of three
meals of a day –although it is not uncommon that it is
consumed as the three meals of a day in some parts of
the forest zones in Cameroon (Abia, 2003)-, despite its
seemingly balanced nature it does not in all cases satisfy
the RDAs of the major consumer populations. These
corroborates with the findings of Horemans and Jallow
(1997). Similarly, protein-energy malnutrition is very like
probably due to dependence on the diet which is
predominantly made up of starchy staple and very little
animal protein (Numfor and Noubi, 1995).
Nevertheless, giving that the contributions made by the
diet to RDAs (whether they satisfactory or not) are not
significantly different from the assumed one third part
(33.33 %) of RDA of each nutrient content, and also due
to the fact that RDAs are a range of safe values and not
requirements, failure to provide recommended amounts
of some nutrient contents is not conclusive of deficiency.
That not withstanding, failure of a diet to provide the RDA
of its consumers is a vital indication of risk of nutritional
deficiency and synergistically infections. Thus, the further
the nutrient contents are below the RDA, the higher the
risk of malnutrition and associated infections. Therefore,
the apparent and reported malnutrition in the Province
may be associated with the predominant dependence on
this popular food, “waterfufu and eru” for proper nutrition
and health.
“Waterfufu and eru” contain the necessary nutrients.
Energy and nutrient contents of a typical serving of the
dish in restaurants in the forest zones of Cameroon does
not in all cases satisfy the recommended daily energy
and nutrient allowances of major categories of
consumers. Though, there is no significant difference (P
> 0.05) between the amount of nutrients provided and the
RDA for these nutrients, nutritional imbalances or
deficiencies are still very likely to occur in communities
which depend predominantly on “waterfufu and eru”.
Further studies on the absorption and bioavailability of
the nutrients, including Vitamin A of “waterfufu and eru”
are necessary. To meet protein allowances, inter-alia,
more meat and less cow skin (“nkanda”) should be used
in the “eru” soup, and/or diet fortification and
supplementation, measures to conserve nutrients during
processing and preparation, as well as the findings of this
study should be made to the awareness and
understanding of the population.
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... Ceci a suggéré cela la dépendance des communautés à l'égard ce régime pour l'approvisionnement en leurs besoins quotidiens peut en partie être responsable de la prédominance rapportée de la malnutrition dans ces secteurs. Il est a suggéré que la nourriture soit améliorée au moment par la fortification et/ou la supplémentation avec les éléments nécessaires(Abia, Numfor et al. 2007). ...
Technical Report
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Some mineral elements in the leaves, peel (periderm) and the tuber (edible portion) of seven cassava cultivars were determined using instrumental neutron activation analysis (INAA). The cassava specimens were made up of three improved cultivars; namely, TMS 30572, (Afisiafi). TMS 50395 (Gblomaduade) and TMS 4 (2) 1425 (Abasa fitaa). The others are a locally produced mutant "Tek bankye" and two landraces "Ankrah" and "Akosua tumtum". A total of 10 elements (Al, Ca. Mg, V. Mn, Na, Br, Cl, Zn, and K) were identified in all the cultivars studied. The tuber portion contained 10 elements while the leaves and the peel contained 8 and 9 elements, respectively. Five of the elements identified (Ca, Na, V, Mg, and Cl) are classified as major elements in human nutrition while three (Mn, V, and Zn) are trace elements. The major elements were detected in high concentration in the peel of most of the cultivars than the edible tuber or leaves. Al was found in very high concentrations ranging from 643.6 to 12610.0 mg/kg in the peel except in "Akosua tumtum" where its concentration was below 100 mg/kg. The concentration of Ca and Mg meets the recommendations made by Subcommittee on Recommended Dietary Allowance (RDA). The presence of five major and three trace elements in the tuber indicates that cassava has a rich mineral source which makes it safe for human consumption.
The cassava core collection (601 genotypes) was evaluated for root and leaf contents of micronutrient minerals, ascorbic acid, and carotene. Wide genetic variability was observed for all measurements, indicating that there is good potential for exploiting and improving the nutritive value of cassava. There seems to be little correlation between the levels of any micronutrient in roots and leaves. There was no clear association between carotene and ascorbic acid concentrations. A genetic study of the progeny of a cross between yellow and white parents indicated control of the yellow trait by only two genes. The stability of vitamins after three commonly used processing procedures was evaluated in a sample of 26 genotypes. A higher proportion of the original vitamin content survived boiling, whereas solar drying resulted in the highest losses. Carotene was more stable than ascorbic acid. In a limited number of lines, there was some indication that higher vitamin content was associated with decreased post-harvest physiological deterioration. Since it is well established that β-carotene and ascorbic acid can enhance the absorption and internal transport of dietary iron and zinc from plant sources, yellow varieties of cassava have potential to address not only vitamin deficiencies per se, but also iron-deficiency anaemia and zinc deficiency. Further, the use of the leaves as a vegetable, as is done in several African countries, can complement the use of the root as a staple because of the high nutrient density of the leaves. The potential to improve the nutritive potential of cassava is exciting.
Severe forms of protein–energy malnutrition still occur, but they are associated most commonly with devastating natural disasters and civil unrest. With the exception of sub-Saharan Africa, progress in combating chronic undernutrition is also occurring. The prevalence of vitamin and mineral deficiencies has also declined in nearly all countries, although the pace is slow for some micronutrient deficiencies, particularly iron-deficiency anaemia. Nevertheless, the prevalence rates of micronutrient malnutrition remain high, with devastating consequences for health, cognition, and productivity. Much remains to be done, particularly in reducing iron, zinc, and vitamin A deficiencies, which up to the present have largely been attacked by using a medical model that relies on the distribution of supplements. Supplements are effective but are expensive in terms of the support devoted to repetitive use of scarce health manpower. Fortification can work in some places. Education and awareness of the public is crucial. The public must not be considered only as the target of imposed interventions. Civil society must become engaged in the process, with the goal of their becoming demanding consumers, participating in the action to achieve micronutrient adequacy. Sustaining the progress that has been achieved will depend on underpinning the medical model with food-based approaches that address multiple nutrient and phytochemical needs for optimal health. Agriculture, by investing in the Green Revolution, can rightly be credited for its contribution to reducing food shortages and the protein–energy malnutrition problem. A similar opportunity exists now for agriculture to invest in developing more micronutrient-dense staple crops, while not neglecting continued research on the production of livestock and small animals, fish, vegetables, and legumes.
B e c a u s e o f p e r s i s t e n t r e p o r t s o f m a l n u t r i t i o n i n s o m e p a r t s o f C a m e r o o n , a p o p u l a r C a m e r o o n i a n f o o d , “ w a t e r f u f u a n d e r u ” w a s a n a l y z e d f o r i t s e n e r g y v a l u e a n d n u t r i e n t c o n t e n t i n o r d e r t o d e t e r m i n e t o w h a t e x t e n t i t s a t i s f i e s r e c o m m e n d e d d i e t a r y a l l o w a n c e s ( R D A ) . R e s u l t s s h o w e d t h a t a v e r a g e s e r v i n g s i z e o f t h e d i s h w a s 4 0 9 g . T h i s a m o u n t p r o v i d e d 6 0 1 k c a l o f e n e r g y , 2 8 1 g o f m o i s t u r e , 8 2 g o f c a r b o h y d r a t e , 3 0 g o f l i p i d s , 1 1 g o f p r o t e i n a n d 5 g o f a s h o n f r e s h w e i g h t b a s i s . M i c r o n u t r i e n t s w e r e f o u n d t o b e 1 4 0 2 m g i r o n a n d 1 2 3 m g z i n c . A f t e r d u e a d j u s t m e n t f o r a b s o r p t i o n a n d b i o a v a i l a b i l i t y a n d c o n s i d e r i n g t h e o n e s e r v i n g s i z e , c o n s t i t u t e d o n e o f a t h r e e m e a l / d a y r e g i m e , a l t h o u g h t h e r e w a s n o s i g n i f i c a n t d i f f e r e n c e ( P > 0 . 0 5 ) , l i p i d , z i n c a n d i r o n c o n t e n t s o f t h e d i s h s a t i s f i e d R D A s o f a l l g r o u p s o f c o n s u m e r s w h i l e e n e r g y v a l u e , c a r b o h y d r a t e a n d p r o t e i n c o n t e n t s d i d n o t . T h i s s u g g e s t e d t h a t d e p e n d e n c e o f c o m m u n i t i e s o n t h i s d i e t f o r s u p p l y o f t h e i r d a i l y n e e d s m a y p a r t l y b e r e s p o n s i b l e f o r t h e r e p o r t e d p r e v a l e n c e o f m a l n u t r i t i o n i n t h e s e a r e a s . I t w a s s u g g e s t e d t h e f o o d b e i m p r o v e d u p o n t h r o u g h f o r t i f i c a t i o n a n d / o r s u p p l e m e n t a t i o n w i t h t h e n e c e s s a r y e l e m e n t s .