Article Type : Research Article
Authors : Ayorinde OJ
Keywords : Unripe plantain peel; Mineral composition; proximate composition; Musa Paradisiacal; Fourier Transform infrared analysis
The
nutritional composition of unripe plantain (Musa paradisiacal) was
investigated. The various parts of the unripe plantain such as the peel and the
fruit were subjected to different preparation processes. The unripe boiled
unpeeled plantain flour (UBUPF), the unripe peeled boiled plantain flour
(UPBPF), the unripe plantain peeled flour (UPPF), and unripe peeled uncoiled
plantain flour (UPUPF). Each sample was characterized using Energy Dispersive
X-ray Fluorescence (EDXRF) for the elemental composition while Fourier
Transform Infrared spectroscopy (FTIR) was used to investigate the presence of
functional groups. Proximate composition of the samples were carried out. The
results showed that potassium (K) is the most abundant element present in the
entire sample showing UPPF with the highest (3.547 weight %), UBUPF (1.046
weight %), UPUPF (0.981 weight %), and the least was obtained in UPBPF (0.869
weight %) while sodium to potassium ratio (Na/K) was less than one in all the
samples an indication of the plantain diet potential to control high blood
pressure and also the calcium to phosphorous ratio (Ca/P) was less than one in
all the processed samples however, the value obtained in UPPF (0.743) falls
within the recommended range since is higher than 0.5 the ratio of Ca/P value
adjudged to be poor. The results revealed that ash content was observed to be
the highest in UPPF (9.25±0.07 %), followed by UBUPF (3.00±0.01 %), UPBPF
(2.31±0.01 %) and UPUPF (2.19±0.01). UPPF has the highest percentage crude
fibre (4.78±0.04 %), followed by UPUPF (4.10±0.00 %), UPBPF (3.96±0.08 %) and
UBUPF (3.48±0.03). The highest percentage carbohydrate (CHO) was recorded in
UPBPF (870.8±0.01) while the least percentage was in UPPF (74.88±0.14). The
FTIR spectra revealed breaking of bonds, formation of new bonds and shifting of
peaks.
Musa paradisiacal
(Plantain) is a fruit crop that is native to tropical regions of Africa, South
America, Central America and Asia. Plantain belongs to the family called
Musaceae and order; Plantaginaceae [1]. It is a stable fruit cultivated and
consumed in sub-saharan Africa particularly in Nigeria. It has been reported by
that over 2.11 million metric tons of plantain are produced in Nigeria annually
and across the continent of Africa, also according to over 10 % calorie are
obtained from consuming plantain [2,3]. Plantain foods are named in different
ways according to the method use in preparing them, for example, when the
plantain is prepared by mixing with boiling water it is referred to as amala
according to Yoruba tribe in the western region of Nigeria. Plantain is a
perennial crop that is about 2-9 inches tall with an underground rhizome. They
are named by counting the number of fingers in the bunch mostly in the southern
part on Nigeria according to [4]. Cultivated plantains found their origin from
two wild diploid species and named accordingly: Musa acuminate which has the
genome AA and Musa balbisiana refers to as BB [5]. The raw fresh green
plantains are edible and suitable for consumption when cooked. Each fruit
measures about 3 to 10 inches or more in length depending upon the cultivar
type. They tend to have coarser external features with prominent edges and flat
surface. Plantain has been the major source of carbohydrates more than 25 % and
provide about 10 % of the daily calorie intake for more than 70 million people
in Africa both rural and urban populace [6].
Plantain is a potential sources of various food products such as
beverages, fermentable sugars, medicines, flavouring, cooked foods, silage,
fragrance, rope, cordage, garlands, shelter, clothing, smoking material and
numerous ceremonial and religious uses [7].
It has been reported by that the extracts from the flower of plantain
ripe and unripe fruits, leaves and stems have been used for the treatment of
numerous human ailments due to their medicinal properties [8]. The major
pharmacological effects of plantain includes hepatoprotive, diuretic,
analgesic, anti-ulcer, wound healing, hair – growth promoter and haemostatic
activity [9]. The peels of plantain are used majorly to feed animals, in
purification and production of several biochemical products. Plantain peel
(plantain skin) is the outer envelopes (covering) of plantain fruit. They are
the by-product of plantain consumption and processing. Plantain peels are used
as food for animals as reported for manufacturing of several biochemical
products and as a result of this removal of the plantain peel, a significant
amount of organic waste is generated but there are some concerns over the
impact of tannins contained in the peels on animals that consume them as
reported [10,11]. Have reported that the potential applications for plantain
peel depend on its chemical composition [12]. Apart from the health benefit
derived from plantain peel, it has constituted environmental nuisance since
they are mostly considered as waste and often disposed of indiscrimately in
landfills, drainages, and road sides therefore become a threat to the
environment [13]. The Plantain peel is made up of about 40 % of the total fruit
weight had reported that plantain peel to have the potential as a promising raw
material with numerous important and useful industrial applications especially
in agro-based industries. Somalia is one of the countries that has considered
and processed plantain peels for use as organic fertilizers and manure to
replenish and improve soil fertilities and subsequently enhance better crop
yield and production [14]. Plantain peels can be used as a substitute for corn
starch in the production of snails’ diet and also incorporate with other waste
materials in the diet of pigs according. However, plantain peels have been used
for the production of important chemicals like ethanol and also alkali for soap
manufacturing. In order to achieve a cleaner and safer environment for humans,
efforts have been made by scientists to prepare polyphenolic resol resins from
the ethanol extract of plantain peels for the adsorption of heavy metals from
industrial effluents since the plantain peels show high adsorption capacity and
retention affinity for lead (Pb), nickel (Ni), and chromium (Cr) [15]. The aim
of this study therefore, is to investigate and compare the nutritional and
proximate composition of peel and pulp of unripe plantain.
Sample Collection
Bunches of matured unripe plantain fruit were
purchased from Uchi market in Auchi, Etsako West Local Government, and Edo
State. All the chemicals and reagents used were of the analytical grade.
Sample Preparation
The unripe plantain fruits were washed with tap water
and followed with distilled water in order to remove the surface dirt. Four
different flour samples were prepared from the unripe plantain.
Preparation of Unripe Boiled Unpeeled
Plantain Flour (UBUPF)
The unripe boiled unpeeled plantains were cut into
small sizes with a stainless steel knife, and boiled in a stainless cooking pot
until it became soft. The boiled plantains were transferred into a
thermostatically controlled oven and allowed to dry for 24 hr at 105ºC. The
dried sample was ground to fine powder using electric grinder and sieved using
100?m size sieve to obtain a finer particle sizes. The obtained powder was
collected and stored in an air tight dry container and labelled unripe boiled
unpeeled plantain flour. (UBUPF)
Preparation of Unripe Peeled Boiled
Plantain Flour (UPBPF)
The UPBPF was prepared by removing the peel (the bark)
and cut into small pieces using a stainless steel knife and boiled in a
stainless cooking pot until it became soft. The boiled peeled plantain was
transferred into a thermostatically controlled oven and allowed to dry at 105ºC
for 48 hr. The boiled peeled plantain was ground using electric grinder and
further sieved to finer particles using 100 ?m size sieve. The resulted powder
was collected and stored in an air tight dry container and labelled unripe
peeled boiled plantain flour (UPBPF).
Preparation of Unripe Plantain Peels Flour
(UPPF)
The UPPF was prepared by removing the peels using a
stainless steel knife. The peels were dried in a thermostatically controlled
electric oven at 105ºC for 48 hr, the dried peels were ground to fine particles
using a grinder and further sieved into finer particles using 100 ?m sieve. The
resulted powder was stored in an air tight dry container and labelled as unripe
plantain peeled flour (UPPF).
Preparation of Unripe Peeled Uncoiled
Plantain Flour (UPUPF)
The procedure in third sample preparation was repeated
for the fourth sample, the unripe peeled uncoiled plantain and labelled as
unripe peeled uncoiled plantain flour (UPUPF).
Proximate Composition Analysis
Samples were analysed
chemically for crude protein, crude fibre, dry matter, ash, fat, and carbohydrate content was determined by
difference technique, which is the addition of moisture, fat, crude protein,
ash, and crude fibre which was subtracted from 100 %, this is the amount of nitrogen free extract
known as carbohydrate ( % carbohydrate = 100 – ( % Moisture + % Crude protein +
% Crude fat + % Crude fibre + % Ash)
according to the official methods of analysis described by the
Association of Official Analytical Chemist [16]. All analysis were carried out
in duplicate.
Elemental composition methods
The samples were characterized for their elemental
compositions using x ray fluorescence (XRF) while the Fourier Transform
Infrared was used for the identification of functional groups in the samples
In their study had reported that trace metals and minerals are group of inorganic substances that occur naturally and account for about 4 % of total human body mass [17]. Table 1 is the elemental composition of the plantain part samples flour (UPBPF, UPUPF, UBUPF and UPPF). Generally, trace elements and minerals are responsible for regulating numerous biological, help in building body structure and also needed for good health. The activities of enzymes as well as electrolytic balance of body fluid are related to the availability of some minerals such as sodium (Na), potassium (K), magnesium (Mg) and zinc (Zn). K has been adjudged as essential and important mineral that has helped to maintain the volume of the body, regulation of muscles and irritability of nerves, control of glucose absorption and enhancement of normal retention of protein during growth had also reported that lack of calcium results in syndrome like rickets and calcification of bone whereas minerals in sufficient quantity ensure the normal physiological functions including the utilization of iron (Fe) [18,19]. The investigation showed that potassium was more than all other elements determined in the samples however has the highest concentration in unripe plantain peel (UPPF, 3.547), followed by the unripe boiled unpeeled plantain (UBUPF, 1.046), unripe peeled unboiled plantain (UPUPF, 0.981) and the lowest concentration was obtained in unripe peeled boiled plantain (UPBPF, 0.869).
Figure 1: The Fourier Transform Infrared of UBUPF.
Figure 2: The Fourier Transform Infrared of UPBPF.
Figure 3: The Fourier Transform Infrared of UPPF.
Figure 4: The Fourier Transform Infrared of UPUPF.
Table 1: The Elemental Composition of the Peel and Pulp of
Unripe Plantain in Weight
Percentage.
Element |
UPBPF |
UPUPF |
UBUPF |
UPPF |
% weight |
||||
Fe |
0.004 |
0.008 |
0.003 |
0.014 |
Cu |
0.001 |
BDL |
BDL |
BDL |
Zn |
0.002 |
0.001 |
0.001 |
0.004 |
Al |
BDL |
0.030 |
0.040 |
0.003 |
Mg |
0.015 |
0.025 |
0.027 |
0.010 |
Na |
0.065 |
0.178 |
0.005 |
0.058 |
S |
0.047 |
0.089 |
0.054 |
0.061 |
P |
0.098 |
0.073 |
0.112 |
0.101 |
Ca |
0.024 |
0.010 |
0.011 |
0.075 |
K |
0.869 |
0.981 |
1.046 |
3.547 |
Mn |
0.001 |
0.002 |
0.001 |
0.006 |
Mo |
BDL |
BDL |
BDL |
BDL |
Na/K |
0.074 |
0.181 |
0.005 |
0.016 |
Ca/P |
0.245 |
0.137 |
0.098 |
0.743 |
BDL: Below Detection Limit |
Table
2:
The Proximate Composition of the Peel and Pulp of Unripe Plantain Sample In
Weight Percentage.
Sample |
UPBPF |
UPUPF |
UBUPF |
UPPF |
Percentage
(%) |
||||
Moisture content |
6.84±0.01 |
7.15±0.01 |
6.91±0.01 |
6.90±0.00 |
Crude protein |
2.65±0.02 |
2.73±0.04 |
3.07±0.01 |
5.24±0.01 |
Ash content |
2.31±0.01 |
2.19±0.01 |
3.00±0.01 |
9.25±0.07 |
Ether extract |
4.16±0.08 |
4.45±0.07 |
3.68±0.04 |
6.50±0.01 |
Crude fibre |
3.96±0.08 |
4.10±0.00 |
3.48±0.03 |
4.78±0.04 |
Dry matter |
92.64±03.73 |
92.86±0.01 |
92.80±0.42 |
92.80±0.42 |
ME(cal/kg) |
3522.67±1.43 |
3530.78±0.71 |
3494.18±1.37 |
3386.14±0.77 |
CHO |
87.08±0.01 |
86.77±0.35 |
86.75±0.01 |
74.85±0.14 |
The
obtained values are averages ± standard deviation of duplicate determinations
|
Table
3:
Fourier Transform Infrared of UBUPF.
Absorption
bands (cm-1) |
Functional
groups |
3810.55 |
OH Stretching (Hydroxyl group) |
3391.02 |
OH Stretching (Hydroxyl group) |
2962.47 |
CH2 Symmetric and asymmetric stretching
vibrations (alkanes) |
2800.91 |
C-H stretching vibration. (alkanes) |
2473.25 |
C=O Stretching (ester group) |
1632.75 |
COOH Stretching (carboxylic group) |
1510.93 |
C-O Stretching vibration (amide I and amide II) |
1203.32 |
C-O-C asymmetric stretching carbonyl (cellulose and
hemicelluloses) |
949.50 |
OH bending and C-O-C bond stretching ( Hydroxyl
ether) |
763.15 |
C-O-C Stretch vibration (carbonyl group) |
642.23 |
C-O Stretching and CH rocking vibration of cellulose
(aldehydes) |
505.47 |
CH2 Scissoring vibrations(alkanes |
Table 4: Fourier Transform Infrared of UPBPF.
Absorption
bands (cm-1) |
Functional
groups |
|
3800.17 |
OH Stretching (Hydroxyl group) |
|
3398.64 |
OH Stretching (Hydroxyl group) |
|
2962.47 |
CH2 Symmetric and asymmetric stretching
vibrations (alkanes) |
|
2473.25 |
C-H stretching vibration. (alkanes) |
|
1678.09 |
C=O Stretching (ester group) |
|
1800.90 |
COOH Stretching (carboxylic group) |
|
1406.33 |
C-O Stretching vibration (amide I and amide II) |
|
1300.28 |
C-O-C asymmetric stretching carbonyl (cellulose and
hemicelluloses) |
|
949.50 |
OH bending and C-O-C bond stretching ( Hydroxyl and
ether) |
|
751.07 |
C-O-C Stretch vibration (carbonyl group) |
|
660.50
|
C-O Stretching and CH rocking vibration of cellulose
(aldehydes) |
|
500.03 |
CH2 Scissoring vibrations(alkanes |
Table
5:
Fourier Transform Infrared of UPPF.
Absorption bands (cm-1) |
Functional groups |
3450.11 |
OH Stretching (Hydroxyl group) |
3341.60 |
OH Stretching (Hydroxyl group) |
2896.37 |
CH2 Symmetric and asymmetric stretching vibrations
(alkanes) |
1600.10 |
C=O and N-H stretching vibrations (amide) |
1450.95 |
C-N stretching vibrations (Cyanide) |
1352.16 |
C-O-C asymmetric stretching carbonyl (cellulose and
hemicelluloses) |
1010.29 |
C-O Stretching vibration of amide I and amide II
(amide) |
921.64 |
OH bending and C-O-C bond stretching ( Hydroxyl and
ether) |
680.90 |
C-O Stretching and CH rocking vibration of cellulose
(aldehydes) |
500.03 |
C=C Stretching vibration (alkenes) |
Table
6:
Fourier Transform Infrared of UPUPF.
Absorption
bands (cm-1) |
Functional
groups |
3386.20 |
OH Stretching (Hydroxyl group) |
1455.31 |
C-N stretching vibrations (Cyanide) |
1362.90 |
C-O-C asymmetric stretching carbonyl (cellulose and
hemicelluloses) |
1223.18 |
C=O and N-H stretching vibrations (amide) |
1078.35 |
C-N stretching vibrations (Cyanide) |
949.03 |
C-O-C asymmetric stretching carbonyl (cellulose and
hemicelluloses) |
800.07 |
C-O Stretching vibration of amide I and amide II
(amide) |
674.21 |
C-O Stretching and CH rocking vibration of cellulose
(aldehydes) |
500.03 |
C=C Stretching vibration (alkenes) |
In his research had
reported that sufficient concentration or quantity of K in the body system
increases utilization of iron which is more beneficial to humans taking
diuretics to control hypertension and
also people suffering from excessive excretion of K through the body system
fluid according to the study revealed the various concentrations of sodium in
plantain parts [20,21]. The highest concentration of sodium was obtained in
(UPUPF, 0.178) followed by (UPBPF, 0.065) then (UPPF, 0.058) and the lowest
concentration was obtained in (UBUPF, 0.005). Sodium (Na) as one of the
minerals needed in the body as reported by regulates fluid balance in the body
and helps in the proper functioning of muscles and nerves [22]. While when the
dietary Na concentration is high leads to cardiovascular and renal disorder as
reported by The results also revealed that the concentration of calcium was
more in (UPPF, 0.075) and the lowest concentration was found in (UPUPF, 0.01)
and 0.024 was in (UPBPF). Calcium is a constituent of bones and help greatly in
concentration process in the body system, clothing of blood and the nerves to
transmit messages. Whenever there is low concentration of calcium in the body,
the body on its own extracts the required and needed calcium from the bones.
Calcium is one of the essential minerals that has found application in disease
prevention and control and therefore play a role in medicinal influence of the
plant [23,24]. The concentration of copper in the samples ranged between 0.0003
and 0.0005 with the highest concentration recorded in UPBPF, 0.0005 and the
lowest in both (UBUPF) and (UPPF) with the value of 0.0003. Copper plays
significant role in helping the body to utilize iron and sugar properly, it
also necessary for the growth of bone and nerve function. Manganese plays an
important role in the formation of connective tissues, bones, nerves, sex
hormones, and clothing of blood. The concentrations of manganese in the
plantain various parts ranged between 0.001 and 0.005. The highest percentage
concentration recorded was in (UPPF, 0.005) and the lowest in (UPBPF) and
(UBUPF) having the same percentage concentration of (0.001). Iron has the
highest concentration in UPUPF. 0.008 And the lowest in fresh unripe plantain
peel, UPPF, 0.01. Iron is an essential element in the diet of pregnant women,
nursing mother and infant to prevent anaemia [25]. The concentration of zinc in
various parts of the plantain was comparatively low but may still play a key
role in normal body development since is an essential element in protein and
nucleic acid synthesis and also is one of the microelements that is required in
a small quantity in the body system and the same with molybdenum (Mo) [26]. The
highest concentration of phosphorous in the sample was obtained in (UBUPF,
0.11). The mineral ratios were also calculated and presented in table 1. Na/K
are less than one (Na/K values < 1) in all the samples investigated. Na/K
plays a significant role in the diet which as a result will helps to control
high blood pressure in the body system. It has been reported that low
concentration of sodium and high concentration of potassium intake helps to
reduce high blood pressure in hypertensive patients [27]. The recommended Na/K
ratio should be less than one. The Na/K values obtained are 0.074, 0.181, 0.005
and 0.016 in UPBPF, UPUPF, UBUPF, and UPPF respectively. This is an indication
that regular consumption of plantain would help in preventing hypertension and
also help in lowering of blood pressure in hypertensive patients. Calcium to
phosphorous ratio (Ca/P) higher than 1 has been reported to be advantageous for
consumption because diet is considered good if the Ca/P ratio is greater than 1
and as poor if less than 0.5 [28]. The results of Ca/P ratio obtained showed
that only UPPF (0.743) contained the highest Ca/P ratio and could be regarded
as suitable among the samples for consumption. The results of the proximate
composition analysis of unripe plantain parts samples were presented in Table
2. The percentage moisture content of various plantain parts; (UPBPF), (UPUPF),
(UBUPF), and (UPPF) shows that the highest percentage moisture content was
observed in UPUPF while the lowest percentage moisture content was in UPBPF.
The results showed that moisture content of the samples were moderate and low,
this is an indication that the samples can conveniently be stored for a longer
period of time as they will prevent efficiently and effectively the growth of
microorganisms therefore increasing the shelf-life. The values obtained in this
study are acceptable for the established aim, with stable shelf-life (< 20 %
moisture) and agreed with those values previously reported by [29-31]. Ash
refers to the concentration of minerals or inorganic residue that remains after
either ignition or complete oxidation of organic matter in a foodstuff. Ash
content is used for nutritional evaluation. The percentage ash content in
unripe plantain various parts; UPBPF, UPUPF, UBUPF, and UPPF ranged from
9.25±0.07 to 2.19±0.01. The highest percentage ash content obtained was in UPPF
(9.25±0.07) and the lowest percentage ash content recorded was in UPUPF.
However, the low percentage ash content obtained in UBUPF and UPBPF was due to
evaporation of some of the volatile minerals as a result of heating. The
highest percentage ash content was obtained in UPPF revealed that the bulk of
the minerals were concentrated in the peels of the unripe plantain
Carbohydrates are
important in foods as a major source of energy, to impact crucial textural
properties, and as a dietary fibre which influences physiological processes.
Carbohydrate also exhibit other attributes such as bulk, body, viscosity,
stability to emulsions and foams water-holding capacity, freeze-thaw stability,
flavour, aromas, and a range of desirable textures and also provide safety. The
results of carbohydrate obtained for the samples by difference showed that the
highest percentage carbohydrate recorded was in unripe peeled boiled plantain
flour (UPBPF; 87.08±0.01) while the lowest was in unripe plantain peel (UPPF; 74.85±0.14).
Comparatively, the results showed that UPUPF is rich in appreciable quantity of
carbohydrate than the UPPF and that the major class of food in unripe plantain
is carbohydrate. The dry matter that remains after moisture removal is referred
to as total solids. The result showed the percentage dry matter ranged between
92.86±0.01 and 92.64±0.73 with the highest value in (UPUPF; 92.86±0.01) and the
lowest in (UPBPF; 92.64±0.73). Dry matter ensures adequate nutrient balance.
Those nutrients that are essential and required to maintain the normal growth
and development of animals, pregnancy during lactation are part of the dry
matter portion of food [32]. Fat are referred to those lipids that are solid at
room temperature. The analysis of fats in foods is important for accurate
nutritional labelling, determination of whether the food meets the standard of
identity, and to ensure that the product meets manufacturing specifications.
Fat values obtained for (UPBPF), (UPUPF), (UBUPF) and fresh unripe plantain
peel were 4.16±0.08, 4.45±0.07, 3.68±0.04, and 6.50±0.01 respectively. The
energy values in various parts of unripe plantain ranged from 3386.14±0.77 to
3530.78±0.71. The highest energy value was obtained in (UPUPF) and the lowest
was in (UPPF). The various proportions of energy contribution were as a result
of fat, protein and carbohydrates. Proteins are an abundant component in all
cells and they are important for biological functions and cell structure except
the storage proteins. The percentage crude protein of unripe plantain various
parts ranged between 5.24±0.01 and 2.65±0.02. The highest percentage crude
protein content obtained was in UPPF, (5.24±0.01) and the lowest percentage
crude protein content recorded was in (UPBPF, 2.65±0.02). The percentage crude
protein content in the study was comparatively low however, the results
revealed that much protein are obtained in (UBUPF) and will enhance protein
content of the body system if consumed than (UPBPF). However, the low values of
percentage crude protein obtained showed that unripe plantain is not rich in
protein and not a good source of protein. In spite of the low protein content,
the percentage crude fibre recorded makes unripe plantain of interest from a
nutritional point of view. Dietary fibre is essentially the sum of the
non-digestible components of a food stuff or food product. Most, though not all
dietary fibre is plant cell wall materials such as cellulose, hemicelluloses,
lignin and made up of polysaccharides molecules. Foods that the body system
cannot digest or absorb are refer to as dietary fibre portion of food according
to [33]. In this study, the fibre content of unripe plantain various parts ranged
between 4.78±0.04 and 3.96±0.08 with the highest percentage obtained in (UPPF,
4.78±0.04) and the lowest was in (UBUPF, 3.48±0.03). Comparatively, the results
showed that (UPUPF) percentage crude fibre was 4.1±0.00 while the (UPBPF) and
(UBUPF) were 3.96±0.08 and 3.48±0.03 respectively suggesting that crude fibre
quantity in the sample was reduced probably due to evaporation during heating.
The percentage quantity of crude fibre obtained in this study showed that
unripe plantain meal will protect against colon cancer, keep blood lipids
within the normal range, thereby reducing the risk of obesity, hypertension,
and cardiovascular disease. It will also help in maintaining and sustaining the
normal peristaltic movement of the intestinal tract which is one of the
important physiological roles that crude fibre plays in the living system. The
results revealed that the fibre was concentrated in the peel which is (UPPF)
and its importance as a source of dietary fibre and will be able to regulate
the normal bowel function
The analytical
techniques for the characterization of the plantain parts samples flour was
achieved using FTIR spectroscopy. The quality features of infrared spectroscopy
have been so useful and of the most effective tools for characterization
especially for functional groups [34]. Figure 1 is the spectrum of UBUPF while table 2 shows the absorption
bands and functional groups of UBUPF. The low intensity peak at 3810.55 cm-1
and broad peak at 3391.02 cm-1 are attributed to hydroxyl group (OH
stretching vibrations and also due to hydroxyl surface). The absorption band at
2962.47 cm-1 is due to CH2 symmetric and asymmetric stretching from
alkyl group while the peak at 2800.91 cm-1 is due to CH stretching
vibration from alkyl group. The absorption band at 2473.25 cm-1 is
attributed to C=O stretching of ester group while the peak that appears at
1632.75 cm-1 is due to COOH stretching. The absorption band at
1510.93 cm-1 is as a result of the presence of C-O stretching
vibration of amide group and probably amide I and amide II. The absorption peak
at 1203.32 cm-1 is attributed to C-O-C asymmetric stretching of
carbonyl group likely a characteristic mode of cellulose and hemicelluloses.
The peak at 949.50 cm-1 represents the characteristic peak of OH
bending vibration and C-O-C bond stretching of hydroxyl ester while the peak at
763.15 cm-1 is attributed to C-O-C stretching vibration of carbonyl
group. However, the absorption peak that appears at 642.23 cm-1 is
due to the presence of C-O stretching and C-H rocking vibration of cellulose.
The peak at 505.47 cm-1 is attributed to CH2 scissoring vibrations
of alkyl group (alkane). Figure 2
is the spectrum of sample UPBPF and table 3 shows the absorption bands and
functional groups of UPBPF. The weak peak at 3800.17 cm-1 and the broad peak
that appears at 3398.64 cm-1 are the characteristic band
corresponding to OH stretching vibrations of hydroxyl group present in the
sample. The appearance of a peak at 2962.47 cm-1 indicates the
presence of CH2 symmetric and asymmetric stretching vibrations of alkane while
the peak at 2473.25 cm-1 is due to CH stretching vibration of
alkanes. The absorption band at 1678.09 cm-1 is attributed to C=O
stretching of the ester group. However, the peak at 1800.90 cm-1 is
due to the presence of COOH stretching of carboxylic and the presence of a peak
at 1406.33 cm-1 corresponds to C-O stretching vibration of amide
(amide I and amide II). The absorption band that appears at 1300.28 cm-1
is a characteristic peak of C-O-C asymmetric stretching mode of cellulose and
hemicelluloses (carboxyl group). The peak at 949.50 cm-1 is due to
OH bending vibration and C-O-C bond stretching of hydroxyl and ether while the
peak at 751.07 cm-1 corresponds to C-O-C stretching vibration
(carbonyl group). The absorption band at 660.50 cm-1 indicates the
presence of C-O stretching and C-H rocking vibration of cellulose (Aldehyde)
and the peak at 500.03 cm-1 is due to CH2 scissoring vibrations of
alkanes. Figure 3 is the spectrum sample of UPPF while
table 4 highlights the absorption bands and functional groups of UPPF. The peak absorption band at 3450.11 cm-1
and weak broad band at 3341.60 cm-1 correspond to stretching
vibration of OH of hydroxyl group. The peak at 2896.37 cm-1 is
attributed to the characteristic band of CH2 symmetric and asymmetric
stretching of alkyl groups (Alkanes) while the sharp band at 1600.10 cm-1
is due to C=O and N-H stretching vibrations of amide. The characteristic
absorption band at 1450.95 cm-1 is attributed to the presence of C-N
stretching vibration (Cyanide). The peak at 1352.16 cm-1 is due to
C-O-C asymmetric stretching mode of cellulose and hemicelluloses (carbonyl
group). However, the sharp absorption band at 1010.29 cm-1
corresponds to C-O stretching vibration of amide (amide I and amide II). The
observed peak at 921.64 cm-1 is attributed to OH bending vibration
and C-O-C bond stretching from hydroxyl and ether respectively while the peak
at 680.90 cm-1 is due to C-O stretching and C-H rocking vibration of
cellulose from aldehydes and the absorption band at 500.03 cm-1 is
an indication of the presence of C=C stretching vibration of alkenes. Figure 4 is the FT-IR spectrum of UPUPF and
table 5 shows the absorption bands and functional groups of UPUPF. The peak at
3386.20 cm-1 is due to OH stretching vibrations of hydroxyl group. The peaks at
1455.31 and 1078.35 cm-1 correspond to CN stretching vibration of
cyanide while the absorption peak that appears at 1362.90 and 949.03 cm-1
are due to C-O-C asymmetric stretching mode of cellulose and hemicelluloses
(carbonyl group). The absorption peak at 1223.18 cm-1 is attributed
to C=O and N-H stretching of amide groups. However, the absorption peak at
800.07 cm-1 corresponds to C-O stretching vibration of amide (amide
I and amide II). The absorption band at 674.21 cm-1 is due to C-O
stretching and C-H rocking vibration of cellulose (Aldehydes) and the peak at
500.03 cm-1 corresponds to C=C stretching vibration of alkenes.
The study shows that different parts of unripe
plantain contain appreciable levels of food nutrients. The proximate analysis
revealed that unripe plantain peel and pulp are rich in nutrients with high
proportion of minerals concentrated in the peel. The high amount of dry matter
present in the samples revealed that the consumption of unripe plantain will
ensure adequate nutrient balance since the nutrients that are essential and
required to maintain the growth of animals and pregnancy during lactation are part
of the dry matter portion of food. The level of crude fibre revealed that the
consumption will also fight against colon cancer, keep blood lipids within the
normal range as a result reducing the risk of obesity, hypertension, and
cardiovascular disease, and it will help maintaining and sustaining the normal
peristaltic movement of the intestinal tract which is one of the important
physiological roles that crude fibre plays in the living system. The result
showed that unripe plantain is an excellent source of carbohydrate and not rich
in protein as low proportion of percentage crude protein were obtained in all
the samples investigated. The peel of unripe plantain contains sufficient
concentration of minerals and therefore can be incorporated into animal feeds
formulation and if successful by extension will enhance solid waste management
and reduce environmental pollution to appreciable level.