African Journal of Biotechnology Vol. 6 (3), pp. 280-284, 5 February, 2007
Available online at http://www.academicjournals.org/AJB
ISSN 1684–5315 © 2007 Academic Journals
Ful Length Research Paper
Losses in -carotene and vitamin C due to frying of
plantain (Musa paradisiaca) chips
Demasse Mawamba Adelaide1, Gouado Inocent1*, Leng Marlyse1, Ejoh Aba Richard2,
Njinkoue Jean Michel1 and Tchouanguep Mbiapo Felicite3
1Department of Biochemistry, Faculty of Science, PO Box 24157, Douala, Cameroon.
2Department of Food Sciences and Nutrition, PO Box 455, University of Ngaoundére, Cameroon.
3Department of Biochemistry, University of Dschang, PO Box 67, Dschang, Cameroon.
Accepted 17 June, 2006
Slices of plantain (unripe and ripe) of 0.5, 1 and 2 mm thickness were fried at 130 ± 5, 150 ± 5
and 170 ± 5°C for 1 to 10 min in refined palm oil. The results obtained showed that -carotene
and vitamin C contents decreased significantly with the elevation of the temperature and
duration of frying (p<0.05). The decrease is more important when the thickness of the slices is
reduced. Water losses and lipids absorption depend also on the temperature, duration of frying,
thickness of plantain and the maturation stage of the plantains. Optimum frying conditions were
plantain slices thickness of 1 mm, frying temperature of 150°C for 5 to 7 min.
Key words: Plantain, frying, chips, -carotene, vitamin C.
Vitamin A deficiency stil remains a primordial cause of
C play a vital role in the stimulation of immunity, and are
morbidity and mortality mostly in developing countries. In
active against cardiovascular diseases and some forms
Cameroon, it is a public health problem with high severity
of cancers. -Carotene supply 70 to 90% of dietary vita-
in al parts of the country (Kol o et al., 2000). Considering
min A (Donald and Martin, 2002).
the different available food sources in the country, seve-
Researches on chips are limited to the determination of
ral sources of vitamin and provitamin A can be identified,
some physicochemical parameters. In view of the role of
but vitamin A deficiency persists due to low availability of
-carotene and vitamin C in human nutrition, this study is
micronutrients in the diet. The amount of micronutrients
aimed at determining the effect of frying on the -
ingested from the diet is often low compared with the
carotene and vitamin C levels of plantain chips. The
unprocessed raw food items. It has been shown that
effects of temperature, duration of frying, plantain slices
provitamin A levels in foods could be reduced by up to
thickness, stage of maturation of the plantain and water
90% by processing (Penelope and Ritu, 2003). In addi-
and total lipids contents of the chips obtained were
tion to supplementation, the use of dietary sources is one
evaluated to provide data on the best conditions for frying
of the principal means of fighting micronutrients deficien-
that wil minimise losses of these nutrients.
cies. The improvement of the food processing methods
for micronutrient rich staples is therefore highly essential.
Processing of plantain into chips is one of the ways to
MATERIALS AND METHODS
reduced post harvest losses of this crop. These chips are
Plantain chips production
highly consumed in Cameroon (Dury et al., 1998). It is
wel known that processing of foods modifies their nutri-
The Big Ebanga variety of plantain and refined CDC (Cameroon
ents contents. Micronutrients like -carotene and vitamin
development cooperation) palm oil obtained from the Douala main
Market were used in the study. The plantain variety has a yel ow
pulp and in Cameroon, it is used regularly to make chips.
Unriped Plantains (green stage) col ected from the market were
divided in two parts. The first part was used immediately and the
second part stored in the laboratory until they were ripe (green with
*Corresponding author. E-mail: email@example.com.
yel ow spots stage) and ready for the production of chips. The
Demasse et al. 281
Figure 1. Levels of -carotene in plantain chips due to temperature, duration of frying and
thickness of the slices.
unripe and ripe plantains were washed, peeled and the pulp was
170°C (about 50% loss) as compared to those fried at
sliced into 0.5, 1, and 2 mm thicknesses. The sliced plantains were
130°C (10% loss). However, the effect of the temperature
immediately fried in oil heated previously at 130, 150 and 170°C
with the ratio of 20 g/l (plantains/oil). The sliced plantains were fried
tends to decrease with the ripening. The loss of -
for 1, 2, 3, 4, 5, 7, and 10 min and divided into 4 portions. The
carotene is significantly different for the different frying
different portions were then stored in dark hermetic smal bottles.
temperatures except in 0.5 mm slices where no
Two portions were immediately used for the evaluation of water and
significant variations were observed when they were fried
vitamin C contents respectively by AOAC method (1980) and
using different temperatures.
titration with 2.6 dichlorophenol indophenol (Harris and Ray, 1935).
Vitamin C losses at the start of frying are high (Figure
The two other portions were frozen at -16oC for 24 h before analysis
of total lipids (Bergeret, 1955) and -carotene by open column
2) especial y when the temperature is highest at 170°C
chromatography (Simpson et al., 1987).
(about 50% loss). Vitamin C losses increase as the
thickness of the slices is reduced. Losses of vitamin C
are significantly higher (P<0.05) for the slices of 0.5 mm
thickness (about 43 to 70% of loss). The rate of vitamin C
Data were expressed as mean and standard deviation. Analysis of
losses increases significantly (P<0.05) with increase in
variance (ANOVA) was used to determine the effect of different
temperature (54 to 70% losses for the slices fried at 150
parameters (temperature and duration of frying, thickness of the
and 170º C against 20 to 43% for those fried at 130ºC).
slices and stage of maturation). The Pearsons linear correlation
was used to determine the relationship between the different
parameters. The least significant difference was also done using
Effects of frying on the total lipids and water contents
the DUNCAN multiple range tests. Al statistical analyses were
done using the SigmaStat program, version 2.03 (SPSS, 1995).
Water losses are higher during the three first minutes of
frying (Figure 3). The extent of losses depends on the
temperature of frying and the thickness of the slices.
Slices of 0.5 mm thickness loose (p<0.05) higher
Effect of frying on vitamin C and -carotene contents
quantities of water (68 to 81%) than 2 mm slices (30 to
65%). However, the effect of the thickness of the slices
The levels of -carotene and vitamin C of chips remaining
decreases with the ripeness. Moreover, slices fried at
after frying are dependent on the temperature of frying,
170ºC loose significantly higher quantities of their water
the duration of frying and the thickness of the slices. -
(p<0.05) (about 60 to 80%) compared with those fried at
carotene losses are significantly higher (p<0.05) for the
130ºC (30 to 70%). The total lipids content of the chips
slices of 0.5 mm slices compared with the other slices
depend also on the duration and the temperature of frying
(Figure 1). About 40, 30 and 20% of -carotene are lost
and the thickness of the slices (Figure 4). Lipids absorp-
from the slices of 0.5, 1 and 2 mm, respectively, when
tion is at the maxi-mum during the first minute of frying
fried at 150 and 170°C. Similarly, -carotene losses are
and this is independent of the temperature of frying and
significantly higher (p<0.05) when the slices are fried at
the thickness of the slices. The quantity absorbed is sig-
282 Afr. J. Biotechnol.
Figure 2. Levels of vitamin C in plantain chips due to temperature, duration of frying and
thickness of the slices.
Figure 3. Levels of water in plantain chips due to temperature, duration of frying and
thickness of the slices.
nificantly higher (p<0.05) when the thickness of the slices
Leng et al. (1997). These authors revealed that the
is reduced. Slices of 0.5 mm thickness absorbed 15 to
increase in thickness of the slices causes resistance to
32% of lipids as against 26 to 23.7% for 1 and 2 mm
the loss of water and absorption of the lipids. This
slices. Furthermore, lipids content of slices fried at 170oC
resistance is eliminated by the softening of the pulp due
is higher (p<5%) (17.4 to 32.4%) than those fried at
to ripening especial y when the thickness of the slices is
130oC (8.7 to 26%).
reduced. This explains why the difference between -
carotene losses of ripe chips of 0.5 mm is not significantly
different. The exchange between water and lipids during
frying were also noted by Guil aumin (1988), Lamberg et
During frying, the thinner the slices, the higher the water
al. (1990) and Raoult-Wack (1994). This confirms the
loss and the lipids absorbed. These results are similar to
significant correlation between water losses and lipids
those obtained in potato by Gamble and Rice (1987) and
absorption. This correlation explains why slices fried at
Demasse et al. 283
Figure 4: Levels of total lipids in plantain chips due to temperature, duration of frying and
thickness of the slices.
Table 1. Correlations between losses of vitamin C, -carotene, water and oil absorption in plantain chips during frying at
130°C 150°C 170°C 130°C 150°C
-0.98 a* -0.97* -0.89* 0.76*
-0.83b* -0.91* -0.88* 0.89*
-0.98* -0.95* -0.95* 0.76*
-0.86* -0.77* -0.92* 0.95*
-0.91* -0.84* -0.89* 0.76*
-0.86* -0.76* -0.73* 0.86*
*5 % significant.
a: Ripe chips.
b: Unripe chips.
130°C which has the high content of water absorbs a
lation is significant for the slices fried at 170°C as com-
lesser quantity of lipids.
pared with those fried at 130°C. It has been showed that
-carotene losses observing during frying may be due
heat brings about cistrans isomerisation of some double
to the heat brought in when oil gets into the slices. This
bonds and the consequence is the modification of the
hypothesis may be true for the moment where the corre-
colour and the nutritional value of the diet (Simpson et al.,
284 Afr. J. Biotechnol.
1987). These results obtained for -carotene is in
Dury S, Bricas N, Tchango Tchango J, Biko A (1998). La consommation
conformity with the observations of Penelope and Ritu
et les critères de qualité du plantain à Douala et Yaoundé In :
(2003) who showed that high temperature and chopping
Bananas and food security. International Symposium. Douala-
Cameroun.10-14 November 1998: 507-523.
lead to -carotene losses. The positive and significant
Gamble MH, Rice P (1987). Effect of pre-fry drying oil uptake and
correlation between the losses of -carotene and water
distribution in potato crisp manufacture. Int. J. Food Sci. Technol.
(Table 1) may confirm the exchange occurring during
frying where oil replaces the holes left by water after
Guil aumin R (1988). Kinetics of fat penetration in food. In: Frying of
food; principles, changes, new approaches. El is Horvood,
diffusion. Similarly, the negative and significant corre-
Chichester, UK. pp: 82 – 92.
lation between oil absorption and vitamin C losses may
Harris IJ, Ray SN (1935). Determination of ascobic acid in urine.
be also due to the heat brought in by the oil during
Method: using titration with dichlonophenol indophenol. Lancet 1(76):
absorption. Furthermore, since vitamin C is water soluble,
Kol o B, De Bernadi R, Sibetcheu D, Nankap M, Tata Ngoh J, Gimpou
it could diffuse simultaneously with the water. This diffu-
MM, hakoua A, haselow NJ (2000). Enquête nationale sur la carence
sion may contribute to the losses during frying as shown
en vitamine A et l’anémie au Cameroun. pp : 60.
by the positive and significant correlation between water
Lamberg I, Hal ostrom B, Oisson H (1990). Fat uptake in potato drying/
and vitamin C losses.
frying process. Lebensm. Wiss. Technol. 23: 295-300
Leng MS, Ndjouenkeu R, Etoa FX, Raoult-Wack AL (1997). Influence
Frying at 150°C for 5 to 7 minutes was also found to be
de quelques conditions de prétraitement sur la cinétique de friture
optimum. A simple regression model was determined
des chips de patate douce. Récent progrès en génie des
only for the variation of the vitamin C losses of ripe chips
procédés.11. 9(59) : 131 – 138.
Penelope N, Ritu N (2003). Food preparation practices can affect
with the equation:
provitamin A carotenoid content and bioavailability. ILSI. Human Nutr.
Insti. pp: 3.
Y = 0.41 – 0.08t – 0.149T + 0.074e
Raoult–Wack AL (1994). Recent advance in the osmotic dehydration of
foods. Trend Food Sci. Technol. 5(8): 50 255 – 260.
Simpson KL, Tsou STC, Chichester CO (1987). Biochemical
Where t, T and e are the duration of frying, temperature of
methodology for assessment of carotenes. Monograph published by
frying and the thickness of the slices, respectively.
IVACG, Washington. pp: 47.
In conclusion, -carotene and vitamin C losses during
SPSS (1995). SigmaStat for Windows version 2.03 Copyright, 1992-
frying are link to the behaviour of physicochemical para-
1997, SPSS Inc.
meters during the water/lipids exchange.
We thank the international Foundation for Sciences (IFS)
and Nutrition Third Word (NTW) for the financial support
offered to the second author through the research grants
no - 35841.
AOAC (1980). Official methods of analysis, 11th ed., WILLIAM
HORWITZ edv., Washington D.C.
Bergeret B (1955). La chimie analytique dans un laboratoire d’outre
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employées au laboratoire de la section l’IECAM- ORSTOM. IRCAM,
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