Volume 3, Issue 10, October – 2018 International Journal of Innovative Science and Research Technology

ISSN No:-2456-2165

Physicochemical and Sensory of Manihot Esculenta

Crantz Characteristics and Manihot Glaziovii
Fermentee (Ntoba Mbodi) to the Congo, Brazzaville
Irène Itoua, Franchelle Constance Bakeni Moukani, Jocelyne Laurence Renée Dhellot, Daniel Massamba, Zacharie Mboungou
Laboratory of Valorization of Agro Ressources (LVAR) ENSP, University Marien NGOUABI
P.O. Box: 69, Brazzaville, Congo

Abstract:- The objective of this study is to characterize increasing; on the other hand, the population of lactic bacteria
and optimize the flavor of the Ntoba mbodi to contribute growing after 24 hours of fermentation and decreases
to the basic knowledge needed to master the sensory thereafter. The proportion of lactic flora compared to the total
properties of the product. Methodology: a study in 2018 on flora decreases of 65% à 4%, during the fermentation than no
the sheets of manihot esculenta crantz and manihot lactic flora increases 34.97% à 95.92% [2]. The flavor of the
Glaziovii fermented (Ntoba mbodi). These sheets were age Ntoba mbodi variations are important (highly significant) and
2 to 3 months. We determined the ash and water content. express (seasonal) trend, according to the species of raw
The potential for the content of hydrogen and titratable material, fermentation conditions and involved
acidity of 10 samples, using or combining chemical raw microorganisms [3]. The sensory response is not only a
materials and various materials in the laboratory. A panel mechanical translation of the evens that occur at the level of
of 31 students was set month training on different answers the receivers; it is a construction in large part of reflection and
on the day of the sensory evaluation on: the color, smell or the sensory response is diverse, unstable over time as a result
aroma and taste. During the tasting, a panel was set up this of the functioning of the nervous system itself and the
to taste these different samples of (A, B and C). Results: conditions of the sample was taken. Also, when it presents
physicochemical aspects, the potential of hydrogen ranged him three products A, B and C, the operator can then ask him
on average between 6.5 and 7.6. The water content was to test discriminative [4].
70.6 - 80.6% and 8.1 - 9.7% in ash. Sensory: light green:
74.1%. Smell of fermented: 93.54%; sweet: 41.9%. The cassava leaves fermentation is a process that
Smooth and soft: 35.45%; rubber: 80.64% and Nice: contributes to the elimination of cyanogenic glucosides in
51.66%. The analysis of variance of the tests of the hedonic more than 70% [5,6,7]. It remains to produce scientific
variables was not significant p≤0.05. All in all, the Ntoba knowledge to support these objectives [8]. The objective of
mbodi is a food fermented potential of hydrogen alkaline this study is to characterize and optimize the flavor of the
food containing very beneficial lactic bacteria for the Ntoba mbodi to contribute to the basic knowledge needed to
digestive system in humans. This production is not the master the sensory properties of the product.
level of instruction, but only the know-how. It would be
necessary to drink more to avoid cancer. II. MATERIALS AND METHODS

Keywords:- Physicochemical characteristics, sensory,  Materials

fermentation, Ntoba mbodi, potential hydrogen. The biological material used, were fermented cassava
leaves. The sheets of manihot esculenta crantz and manihot
I. INTRODUCTION Glaziovii (commonly called rubber) ages from 2 weeks to 3
months which were used for the production of the Ntoba
The Ntoba mbodi is a food fermented cassava under mbodi (fermented cassava leaves). We used material at the
various packaging leaves (leaves of pay, tablecloth plastic...). laboratory: PH meter, beaker, Erlenmeyer and spatula for the
It is produced in the Congo and in the Northwest of Angola, in determination of the pH meter. Vial, Erlen Meyer, magnetic
country Kongo and Teke. It is a customary product highly stirrer, Wash bottle, Burette, spatula, beaker, bar magnet to
prized for its taste and unique aroma. The interest of cassava determine determination of titratable acidity; Distilled water,
leaves lies in their high protein content and more in the quality buffer, phenolphthalein, and soda (NaOH) Solution chemicals
of the amino acids that make up these proteins [1]. and in the end, freezing, the scale accuracy, cremation oven
and Proofer for various use.
Unfortunately leaves of cassava being spontaneous
fermentation, one can imagine the variety of final products
due to their organoleptic characteristics and health risks that
this represents. Indeed, during fermentation, total microflora is

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Volume 3, Issue 10, October – 2018 International Journal of Innovative Science and Research Technology
ISSN No:-2456-2165
 Methods III. THE INTERPRETATION OF THE DATA &
The principle was as follows: in a beaker, it mixed 5g of RESULTS
leaves of cassava fermented or Ntoba mbodi with 20 milliliters
(ml) of distilled water, then they waved to homogenize; We The physicochemical characterization of the leaves of
made a buffer solution to potential hydrogen (pH) 4 at a cassava fermented or Ntoba mbodi features physicochemical
temperature of 25 ° c with 40ml of distilled water, that we then of fermented cassava leaves Potentiel d’Hydrogène (Ph), ash
plunge a pH meter digital and got the values of PH ranging and water content are represented in the tables) following:
from 3.7 to 4. The pH meter so immersed in him filters which,
after a few seconds did appear the pH value of the product. Sample/ 1st 2nd test 3rd test Average
The same procedure was repeated with the rest of the samples. pH test
The rate of ash allows judging the purity and the rate of 1 6.5 6.6 6.5 6.5
minerals of a product. To make, it weighs 5g of raw materials 2 7.2 7.0 6.9 7.0
in electric heating furnace for 8 hours at a temperature of 550 3 6.0 6.9 7.1 7.0
° c and you get a residue after incineration. This content is 4 7.2 7.3 7.2 7.2
determined according to standards NF. T76.110 of September 5 7.4 7.6 7.5 7.5
1981. Ash (%) =M_1-M_2 /M_1-M0 *100 With: M0=Mass 6 7.3 7.3 7.9 7.1
of the cup is empty; M1: mass of raw material; M2: mass of 7 7.2 7.1 7.2 7.1
the sample after incineration. The water content of the product 8 7.2 7.1 7.2 7.1
is loss of water it when it is subjected to the experimental
9 7.2 7.1 7.2 7.1
conditions (by drying of the product the oven) until a constant 7.8 7.4
10 7.6 7.6
weight of the dry product. The water content is calculated as
Table 1:- pH of fermented cassava leaves or Ntoba mbodi
following: H2O (%) =M_1-M_2 /M_1-M0 *100.

 Analysis sensory Samples Water content (%) Ash content (%)

1 76.2 8.1
Preparation of 31 panelists over six months to the
2 80.0 9.7
recognition of the aromas (smells) and flavour of the products
was carried out by the panelists had varying between 17 and 3 78.13 8.7
25 years old. They recognized what was contained in the 4 70.6 8.6
samples; this initiated age group has not experienced 5 78.9 9.6
difficulties with the tasting. 6 77.6 9.1
7 80.6 7.6
 Calculated statistical analysis 8 77.3 8.1
The data were entered and analyzed by the Statistical 9 77.8 8.1
Social Science (Spss) Version 17.5 Package software (Word 10 78.8 9.1
2010 and Window - 8) [9]. The results are given in table Table 2:- Water and ash of fermented cassava leaves or Ntoba
form. The average was calculated variables on the titratable mbodi
acidity and percentage of several. Also, we conducted the
analysis of variance of the hedonic test which was carried out The table 1, the highest average of pH was found at the
according to the method of Duncan with 10 tasters on a scale level of the 10 sample amounting to 7.6.
of 1 to 5 (or 5 levels) by indicating their level of appreciation,
respectively: I don't like, I like a little I love, I love, I love As shown in Table 2, the highest water content was 80.4
with the characteristics: color, texture to the touch, smell or percentage (%) of the sample 7. However in ash was 9.6% of
aroma, flavor, flavor and texture in the mouth. The three the sample 5.
samples, are the leaves of cassava fermented with salt to 4%
(E2), 6% (E3) and sample (E1) (leaves of cassava fermented
without salt) cooked or Ntoba mbodi. The difference was not
significant with p≤0.05.

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Volume 3, Issue 10, October – 2018 International Journal of Innovative Science and Research Technology
ISSN No:-2456-2165
Samples Color N % Aroma or smell , N % Taste or flavor N %
Light green 13 41.9 Smell of smoke 15 38.7 Smoke 4 19.20
S.A Tends green - - Smell of fermented 17 54.8 Fermented 1 3.22
Dark green 2 6.45 Smell of rot 1 3.22 Smoke 6 19.35
Brown green 16 51.6 Rear taste - -
Bitter 3 9.67
Sugar 5 16.12
Fermented 10 32.25
Leaves cente 1 3.22
Sale 1 3.22
S. B Light green 23 74.1 Fermented smoke 1 3.22 Leaf 3 9.67
Dark green 8 25.8 Smell smoke 2 6.45 Fermented - -
Smell of fermented 24 77.41 Smoke 3 9.67
Smell of burnt 1 3.22 Acid 3 9.67
Smell of leaves 2 6.45 Astringent 2 6.45
Smell of rot 1 3.22 Rear-taste - -
Sugar 6 19.35
Bitter 6 19.35
Fermented 11 35.48
Cooked leaves 1 3.22
Earthy 1 3.22
S.C Light green 17 54.83 Smell of fermented 29 93.54 Fermented 3 16.12
Dark green 14 45.16 Smell of rot 2 6.45 Smoke 2 6.45
Acid 4 19.20
Earthy 1 3.22
Sweet 13 41.9
Bland 1 3.22
Astringent 1 3.22
Table 3:- Vocabulary generated by a panel of 31 students during the tasting of the leaves fermented cassava or Ntoba mbodi (color,
smell or aroma and taste or flavor)
The percentages (%) highest on the 3 samples (S) were represented as suite: In Color: light green the Number of subjects (N)
was 23 = 74.1%. Aroma or smell: smell of fermented: 93.54%. Taste or flavor: sweet = 41.9%.
Samples Texture to the touch N % Texture in the mouth N % Flavor N %
S.A Soft smooth 6 19.35 Rubber 25 80.64 Medium nice 14 45.16
Fermented 2 6.45 Hard 2 6.45 Nice 3 41.93
Hard 3 9.67 No sticky 1 3.22 Unpleasant 3 16.12
Sticky 3 9.67 Fluffy 2 6.45 Very nice 1 3.22
Smooth 8 25.80 Bland 1 3.22
Soft 1 3.22
Tender 7 22.58
Fluffy 1 3.22
S. B Soft tender 5 16.1 Rubber 25 50.64 Nice 16 51.66
Little tender 3 9.67 Hard 2 6.45 Medium nice 13 41.93
Smooth 11 35.45 No sticky 1 3.22 Unpleasant 2 6.45
Soft 7 22.58 Fluffy 2 6.45
Rough 1 3.22 Bland 1 3.22
Tights 4 19.20
S.C Soft 11 35.45 Rubber 22 70.96 Nice 15 48.33
Fermented 4 19.20 Bland sticky 2 6.45 Unpleasant 13 41.93
Smooth 7 22.58 Soft 3 9.67 Nice Medium 3 9.67
Soft 3 9.67 Soft sticky 3 9.67
Soft smooth 1 3.22 Hard 1 3.22
Hard 5 16.12
Table 4: Vocabulary generated during the tasting of fermented cassava leaves by a panel of 31 tasters (Texture and flavor) (Sample
(S), Percentage (%) and Number of subjects (N)

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Volume 3, Issue 10, October – 2018 International Journal of Innovative Science and Research Technology
ISSN No:-2456-2165
The samples were the following: -A sample: Manihot Glaziovii (fermented without salt or sample sheets); -sample B: Manihot
esculenta crantz (leaves of cassava fermented with salt to 4%); and the C sample: Manihot esculenta crantz (leaves of cassava
fermented with salt to 8%). The texture to the touch; the smooth and soft were 35.45%; the texture in the mouth of the sample A,
presented a percentage the more 80.64% and the flavor was nice: 51.66%.

Variables Source of variance

Dl SS SM P
a. The sweet flavor
29 147 - ≤0.05
2 0.2 0.1 - // -
9 4.09 0.44 - // -
18 17.47 0.58 - // -
b. the bitter taste
29 58.97 - - // -
2 6.87 3.43 - // -
9 12.97 1.44 - // -
18 18.13 1.007 - // -
c. The texture in the mouth (soft)
29 63.7 - - // -
2 12.6 6.3 - // -
9 16.7 1.85 - // -
18 13.4 1.91 - // -
d. The flavor
29 20.17 - - // -
2 0.27 0.14 - // -
9 3.5 0.50 - // -
18 16.4 0.94
Table 5: Analysis of variance for the hedonic test

As shown in Table 5, the Degree of liberty (DI), Sum of of the product (Ntoba mbodi). These leaves have also played a
square (SS) and Square medium (SS) and the difference was protective role; it prolongs the life of the product.
not significant on all of our variables.
There are many methods of manufacture of ntoba mbodi
IV. DISCUSION among the different producers surveyed:- 30% observed
fermentation in jars tightly closed to prevent the penetration of
The population of 500 women, we conducted a raffle of the flies that could contaminate the product and lead to the
a sample of 50 women producers of Ntoba mbodi ranging in microbial alteration. Those who observed the fermentation in
age between 40 and 60 years. This method allowed us to have the bags (bags used for packaging of sweat and flour) were
the reliability of the sample selected because all the producers 40%. Indeed, the bag according to them was practiced for
of women at all levels are able to produce the Ntoba mbodi. fermentation and required too much surveillance before the
The duration of fermentation varied between 3 and 5 days, but flies that were agents of handling food with food from their
some women gave reasons related to the duration of toxins. -30% of producers have used the leaves of papaya for
fermentation of 5 days: during the dry season. Unlike the rainy fermentation. It turns out that content papaya papain sheet
season or hard fermentation often 4 days it is as well as the which is an enzyme used to cut the hydrogens of links. The
traditional manufacturing of ntoba mbodi is a multi-step risk of penetration of the drug in the product is very large, that
process, the most important being the fermentation phase should cover the product with a bag or a place in a pan, where
which lasts for 4 days. In addition, it produces a significant to put them in a bag for a successful fermentation without
alteration of Ntoba mbodi [6]. That is why there is the penetration insects. The average of the Ph varied between 6.5-
presence of the heat which contributes to the softening of 7.6 (table 1). 1 sample had average less than 7; he has been
cassava leaves. More than 5 days of fermentation, we attended close to neutrality. 2 to 10 samples showed averages of pH ≥7.
products of alteration as many authors have mentioned [10].
On the other hand, the Ntoba mbodi can be marketed and the The salt used during the fermentation of cassava leaves
types of packaging used were the leaves of taro leaves biloria was not too influenced on the variation of the pH. These
(wild plant) and the leaves of the plant (often used in the results are similar to those found by [11]; the pH reaches the
packaging of the chikwangue) which are used to manufacture maximum value of 7.95 to 72 hours of fermentation. It turns
out that the production of the rich ntoba is accompanied by an

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Volume 3, Issue 10, October – 2018 International Journal of Innovative Science and Research Technology
ISSN No:-2456-2165
important alkalization (pH 8.89), functionality found in other However, others say that fermented cassava leaves are
products such as of dawadawa (pH 8.6), fermented Chinese rubbers, hard, soft, the highest percentage was found in the
(pH 8.7) and the iru (pH 7.9), ogiri (pH 7.9), natto (pH 8.4) sample. It turns out that these comments are contradictory:
[5.12]. This means that the increase in pH is a determining panelists 41.93% saw a lovely flavor in the sample against
factor in the microbial competition, explained that the kinetics 16.12% members of the panel observed that the fermented
of evolution of the Ntoba mbodi microflora, which differs leaves a bad taste and 45.16% said it is fairly nice. While for
from the fermentation of other compounds of plant origin. The sample B: 51.66% of panelists found pleasant fermented
water content of fermented cassava leaves or Ntoba mbodi leaves, 41.93% found it's moderately pleasant and 6.43% of
was extended between 70.6 - 80.4% and ash was between 7 panelists found a bad taste. With regard to the sample C:
and 9.6% (table 2). However, the results found by [1] were 85 48.33% panelists perceived a good flavor and panelists
percent water and 8% in ashes. Compared to our results, we 41.93% judge, however, that the taste is not good.The analysis
will tell that the water content was lower and upper ash from of variance for the hedonic (table 5) test has been made with
their results found. The ash content of potato soft leaves several variables: the sweet flavor, the bitter taste, flavor,
concluded [13] this was 2.0, which was below our results. In texture in the mouth (soft). The DUNCAN test, allowed us to
addition, we will also say fermented cassava leaves have a conclude that there is no significant difference (p≤005)
difference in water content and ash. Thanks to its high content, between the averages of pleasant results for three samples of
the Ntoba mbodi is a key molecule for the synthesis of Ntoba mbodi all the variables.
compounds such as vitamins A and E, geraniol and
derivatives. It also reduces sensitivity to pain by increasing V. CONCLUSION
morphinopeptides endogenous [14]. It turns out to be in good
health, men need a range of macro and micronutrients in The objective of this study is to characterize and
quantity sufficient but not excessive. optimize the flavor of the Ntoba mbodi to contribute to the
basic knowledge needed to master the sensory properties of
The Ntoba mbodi fermented cassava leaves were the product. Physical-chemical and sensory characteristics
considered to be a food rich in macro and micro nutrients [15] obtained were determined. The results of the various analyses
like the wild N. hallé isenguesis cuervea [16]. The testify to the ability of Ntoba mbodi; the technique tested for
investigation to identify the criteria generally used to enjoy this purpose is suitable for small scale production. The overall
focus them of various preparations. The criteria generally used perception of the consumer on the Ntoba mbodi confirms its
were the following: color, aroma, smell, taste or flavor, touch good acceptability by the panel of tasters and the production
and texture in the mouth, the texture in the mouth (soft), of ntoba mbodi is not the intellectual level that can have an
Texture to the touch and in the mouth, rubbers, hard and other individual. The sensory evaluation we discovered that in all
variables cited, such as perceived by the consumer. In samples the difference was not significant. It is necessary that
addition, vocabulary generated by a panel of 31 students we adopt measures of processing of cassava leaves respecting
during the tasting sheets of fermented cassava or Ntoba mbodi the conservation of the rules of hygiene. We can measure the
(color, smell or aroma and taste) (table 3). The perceived interest that may represent the leaves of cassava fermented by
colors were the following: green light 41.9%, black green the safety provided by cooking and benefits provided by the
51.6% for a sample of dark green 74.1% and green light Ntoba mbodi on health.
25.8% of the B sample; Black Green 54.83% panelists were - In mechanizing agriculture and developing processing
able to perceive this color; 45.16% tasters have been able to industries and manufacturing could not extend the shelf life of
perceive this color for sample C. It is ' was 38.7% were able to Ntoba mbodi?
smell smoke, 54.8% were able to feel the smell of fermented - Are there any other methods physicochemical and sensory of
and 3.22% is that a person could feel the smell of rot. The cassava leaves?
sample B, 77.41% of panelists were able to feel the smell of
fermented sample C, 93.54% of the panelists were able to feel
the smell of fermentation. 19.35% members of the panel have
been able to perceive a bitter flavor, 16.12% panelists saw a
sweet in the sample, a taste. For the B sample; 9.67%; 6.45%;
19.35% and 19.3% were able to perceive the bitter and
astringent taste sweet and bitter respectively. On the sample C:
the highest percentage was 41.9% of the members of the panel
who perceived respectively acid, sweet and astringent flavors.
The vocabulary generated during the tasting of fermented
cassava guided by a panel of 31 tasters (Texture and flavor)
(table 4). Some say that the leaves are soft, smooth, sticky and
hard (texture to the touch) and the highest percentage found in
smooth and tender 35.45% in samples B and C.

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Volume 3, Issue 10, October – 2018 International Journal of Innovative Science and Research Technology
ISSN No:-2456-2165
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