Influence of Partial Substitution of Wheat Flour with Banana (Musa paradisiaca var. Awak) Flour on the Physico ' Chemical and Sensory Characteristics of Doughnuts

Text-only Preview

International Food Research Jour Influence of Partial Substitution of Wheat Flour with Banana
nal 15(2): 119-124 (2008)
(Musa paradisiaca var. Awak) Flour 119
Influence of Partial Substitution of Wheat Flour with Banana
(Musa paradisiaca var. Awak) Flour on the Physico –
Chemical and Sensory Characteristics of Doughnuts
Chong, L. C. and *Noor Aziah, A. A.
Food Science and Technology Division, School of Industrial Technology,
Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia
Abstract: Evaluation on the physicochemical and sensory properties of wheat flour doughnuts substituted
with banana flour (BF) was investigated. Wheat flour was substituted with green banana (Musa paradisiaca
var. Awak
) flour at 0% (control), 10%, 20% and 30% levels in yeast-raised doughnut prepared by the
straight dough method. Chemical (moisture, fat, protein, ash, carbohydrate, crude fibre, total dietary
fibre and caloric content), physical (volume, specific volume and colour) and sensory evaluation were
conducted on all samples. Chemical analyses result indicated a higher percentage of total dietary fibre
and caloric content in doughnut substituted with BF than the control. Colour evaluation showed that the
dough, crust and crumb of doughnut with BF ranged from 68.97 ± 0.59 – 84.78 ± 0.16 (red – yellow
quadrant). The change from light to darker colour correlated with the amount of BF added. Results also
showed that the volume and specific volume was significantly affected (p < 0.05) by levels of BF substituted.
Doughnut substituted with 20% BF showed the highest score in overall acceptability (6.71 ± 1.40).
Keywords: Doughnut, green banana, banana flour, dietary fibre, caloric
Musa paradisiaca is a type of plantain, usually
is cooked before eaten and Musa paradisiaca var.
Doughnut is a fermented, fried snack which is one
Awak or locally known as ‘pisang awak’ is widely
of the most popular fried products throughout the
grown throughout Malaysia. Plantain is rich in
world (Hatae et al., 2003; Rehman et al., 2007).
starch (14% - 23% on a fresh weight basis) and
Doughnuts are made by deep-frying dough that is
therefore is considered as a possible source of
a mixture of flour, water, egg, oil, sugar and milk
starch for the food industry. Matured green banana
(Hatae et al., 2003). Doughnut made from non-
can also be processed into flour and used as a
enriched wheat flour lacks other essential
source of starch which can be added to food. The
nutritional composition such as dietary fibre,
flour can then be incorporated as an ingredient
vitamins and minerals that are lost during the
for bakery products which enhances the product’s
process of wheat flour refinement.
nutritional value.
Banana belongs to the family Musaceae, genus
At present, there is an increasing interest in
Musa and is a general term embracing a number
fruits rich in dietary fibre that is associated with
of species or hybrids in this genus. Bananas are an
health promoting abilities. According to Chen and
important food crop in many countries and grown
Anderson (1986), consumption of dietary fibre can
extensively in the tropical and subtropical regions.
prevent chronic diseases such as cardiovascular
The worldwide production of bananas in 2001 was
diseases, diabetes and colon cancer. Bananas
66.5 million metric tonnes (FAO, 2002) and
contain high amounts of essential minerals such
increased to 102 million MT of which 68% was
as potassium, magnesium and various vitamins such
banana and 32% plantain (FAO, 2003). Banana is
as A, B , B and C. Besides nutritional and health
consumed directly as raw, ripe fruit or processed
values, bananas have economic gains, as mass
into pulp-liquid fruit, canned slice, deep-fried
production of banana flour (BF) will increase the
chips, toffees, fruit bars, brandy and others
demand for green bananas. This will encourage
(Kachru et al., 1994).
*Corresponding author
E-mail: [email protected]
International Food Research Journal Vol. 15, 119-124

120 Chong, L. C. and Noor Aziah, A. A.
farmers to keep on tending the banana crop, as
Evaluation of Doughnut
value of the banana will increase along with its
(i) Chemical Analysis
Despite being a good dietary source, processed
Proximate Analysis
green mature banana flour has not been utilized
Moisture, crude protein, ash, crude fat and crude
as a food source to its full potential as an ingredient
fibre contents of noodles were determined
in bakery product–doughnut. The purpose of this
according to the AACC (2000) method. Protein
investigation was to evaluate the effects of
content (%N x 5.7) was determined by the Kjedahl
substituting various amounts of wheat flour with
method. Moisture was determined by oven drying
BF into doughnut on chemical composition,
for 4 hours at 100-105oC. Ash was measured by dry
physical and sensory attributes.
combustion [AACC, 2000 (Method 08-01)]. Free
lipids were measured by petroleum ether
extraction, followed by evaporation to constant
weight [AACC, 2000 (Method 30-25)]. Crude fibre
was determined according to the procedure of
AACC, 2000 (Method 32-07). Available
Mature green banana (Musa paradisiaca var. Awak)
carbohydrate was calculated as 100% - (% moisture
was obtained from a local market in Penang and
+ % ash + % fat + % protein + % crude fibre). All
processed into flour according to a modified
samples were done in triplicate.
method reported by Collins and Temalilwa (1981).
Bread flour, dry yeast, full cream milk, vegetable
(ii) Caloric Values
shortening, emulsifier (Glyceryl monostearate,
Caloric values for all samples were determined by
GMS), baking powder and ascorbic acid were
calculation. Percentages for protein, crude fat and
obtained from Sunshine Trading, Penang. Eggs,
carbohydrate were multiplied with their respective
salt and sugar were purchased from a local mini
factors. Caloric value (kcal/100g) = (% protein x
market in Penang. All the chemicals used were of
4) + (% crude fat x 9) + (% carbohydrate x 4). All
analytical grade and purchased from Sigma
samples were done in triplicate.
Chemical Company.
(iii) Total Dietary Fibre
Preparation of Doughnut
Dietary fibre content was determined by enzymatic-
Doughnuts were prepared by the straight-dough
gravimetric method according AOAC, 1990
method according to modified formulation
(Method 985.29). Samples of dried and fat-free
(Braden, 1976). Ingredients consisted of wheat
were gelatinized with heat stable -amylase and then
flour: 100%, water: 36%, shortening: 18%, egg:
enzymatically digested with protease and
10%, sugar: 6%, milk powder: 6%, baking powder:
amyloglucosidase to remove the protein and starch
1.4%, dry yeast: 1.12%, salt: 1%, emulsifier: 0.2%
present in the samples.
and ascorbic acid: 0.01%. A portion of wheat flour
was replaced with an equivalent portion of BF
(iv) Physical Measurement
(10%, 20% and 30%) and water was adjusted to
The volume of doughnuts was determined using
produce a desired dough consistency. All
the volume replacement method (AACC, 1984)
ingredients were electrically mixed (Kitchen Aid,
and they were weighed after cooling for 30 minutes
model: K5SS, USA) for 1 minute at speed 2 with
at ambient temperature. Three samples were
the exception of shortening which was added later
randomly selected from each doughnut for
and mixed for another 10 min at speed 6. Mixing
physical measurements. Crumb and crust colour
was further continued for 5 minutes at speed 8.
of doughnuts were measured by using Minolta
The mixed dough was rested for 10 minutes at
colorimeter (model CM – 3500d) for Lightness
ambient temperature. The dough was sheeted to
(L*) and Hue values.
12 mm thickness and cut with a doughnut cutter
having a diameter of 6 cm. The cut pieces were
(v) Sensory Evaluation
then placed on a greased tray, covered with a damp
A 9 point Hedonic scale rating was used in
cloth and proof for 30 minutes. The doughnuts
evaluating the sensory attributes of doughnuts,
were then deep-fried in corn oil at 185 ± 5oC on
where 1 = dislike extremely and 9 = like extremely.
each side for 1minute.
The attributes evaluated were colour, odor,
elasticity, hardness, oily, flavour and overall
acceptability. Twenty panelists comprising of (10
males and 10 females) students and staff of the
International Food Research Journal Vol. 15, 119-214

Influence of Partial Substitution of Wheat Flour with Banana (Musa paradisiaca var. Awak) Flour 121
Table 1: Proximate composition of control and different levels of Banana Flour (BF)
– incorporated doughnuts*
Composition (% db)
10% BF
20% BF
30% BF
Moisture content
32.87 ± 0.10c
30.04 ± 1.13bc
28.33 ± 1.04b
22.96 ± 0.92a
Crude fat
24.30 ± 0.71a
28.58 ± 0.11b
27.65 ± 0.05b
31.44 ± 0.78c
Crude protein
12.19 ± 0.01a
10.58 ± 0.56b
9.14 ± 0.34c
8.37 ± 0.62c
2.12 ± 0.03a
2.10 ± 0.04a
2.03 ± 0.07a
2.24 ± 0.08b
Crude fibre
1.89 ± 0.13a
2.53 ± 0.64b
4.72 ± 0.12c
5.46 ± 0.66d
28.75 ± 1.01bc
26.17 ± 2.11a
28.13 ± 1.44bc
29.53 ± 1.63c
Values followed by the same letter in the same row are not significantly different (p < 0.05)
* Mean ± standard deviation (n = 3)
School of Industrial Technology Department
1996) and thus corresponds to the higher mineral
participated in the evaluation.
content (especially potassium) in BF which
contributed to the significantly higher ash content
(vi) Statistical Analysis of Data
in BF (3.7%; Suntharalingam and Ravindran,
Data were analyzed with SPSS version 11.0 (Illinois,
1993) than wheat flour (0.43%; Watt and Merrill,
U.S.A) using one-way Analyses of variance
1963). Percentage of crude fibre in BF doughnut
(ANOVA). Significant differences were tested using
was higher than the control and increased
the Duncan Multiple Range test. Three replications
significantly as wheat flour was substituted from
were used for chemical and physical measurements
10% to 30% BF into doughnut. The relatively high
and two replications for sensory evaluation.
percentage of crude fibre content was contributed
from the hemicelluloses in the flour produced
from green banana (Kayisu et al., 1981). However,
the percentage of crude fibre was lower compared
to that of total dietary fibre (Table 2). This could
Proximate composition results for fried doughnuts
be attributed to the solubilisation of
are shown in Table 1. The results indicate a
hemicelluloses in alkali during the gravimetric
decrease in moisture content with increase in
determination of crude fibre. The carbohydrate
percentage of banana flour (BF).The moisture
content in samples ranged from 26.17% to
content in BF-incorporated doughnut was found
to be significantly lower (p < 0.05) than the control.
The soluble (SDF), insoluble (IDF) and
This may be due to the low water holding capacity
total dietar y fibre (TDF) contents of BF-
for banana starch than wheat starch. This was also
incorporated doughnuts are shown in Table 2. BF-
reported by Ibadan et al. (1992). The water content
incorporated doughnuts had signifi-cantly (p <
from the doughnut could have evaporated during
0.05) higher content of SDF, IDF and TDF than
the deep – fat frying process. Therefore with high
the control. Ultimate increase in SDF, IDF and
percentage of BF there will be more water loss from
TDF contents were also noted with increased levels
the doughnut during deep frying. Similar results
of BF added. The higher content of IDF than SDF
were reported for French fries by Krokida et al.
in BF-incorporated doughnuts was due to the fact
(2000). There was an increase in the percentage
that green banana are high in IDF such as cellulose
of crude fat with increase in BF in the doughnuts.
(1.42 ± 0.02%), hemicelluloses (6.08%) and lignin
This could have contributed by the increase in fat
(0.14 ± 0.02%) (Kayisu et al., 1981).
with increased in level of BF due to the oil absorbed
Caloric values for BF-incorporated doughnuts
to replace the pores. Similar obser vation was
were significantly (p < 0.05) higher than the
reported by Mellema (2003) for fried food. The
control (Figure 1). Caloric content was closely
protein content of BF doughnuts was significantly
related to the fat content of doughnuts due to fat
lower (p < 0.05) than the control and an inverse
absorption during frying. Therefore, higher fat
relationship with the amount of BF added. This
content in doughnut indirectly increased the
was due to the relatively low percentage of protein
caloric value of the doughnut.
in BF as compared to wheat flour. The 30% BF
Volume of the control sample was higher and
doughnuts was significantly different in ash content
significantly different (p < 0.05) from doughnuts
compared with the other samples. The ash content
incorporated with BF. The volume decreased with
depends on the quality available in the flour (Kim,
increase in BF as shown in Figure 2. This decrease
International Food Research Journal Vol. 15, 119-124

122 Chong, L. C. and Noor Aziah, A. A.
Table 2: Soluble dietary fibre (SDF), insoluble dietary fibre (IDF) and total dietary fibre (TDF)
contents of control and different levels of banana flour (BF) – incorporated*
SDF (% db)
IDF (% db)
TDF (% db)
1.09 ± 0.04a
1.99 ± 0.08a
3.07 ± 0.11a
10% BF
2.08 ± 0.04b
3.44 ± 0.06b
5.51 ± 0.85b
20% BF
2.16 ± 0.04b
4.40 ± 0.06c
6.56 ± 0.92c
30% BF
2.17 ± 0.05b
4.72 ± 0.82c
6.89 ± 0.18c
Values followed by the same letter in the same column are not significantly different (p < 0.05)
* Mean ± standard deviation (n = 3)
Figure 1: Caloric content (Kcal) for four different formulation of doughnuts.
Same letter on the bars of four different formulation of doughnut were not significantly different (p < 0.05)
*BF = Banana Flour
Figure 2: Volume and specific volume for four different formulations of doughnuts
Same letter on the bars and points of four different formulation of doughnut
showed no significant differences (p<0.05)
*BF = Banana Flour
International Food Research Journal Vol. 15, 119-214

Influence of Partial Substitution of Wheat Flour with Banana (Musa paradisiaca var. Awak) Flour 123
Table 3: Lightness (L*) and hue value of dough, crust and crumb for control and
ultimate level of BF – incorporated doughnuts #
Hue value
Hue value
Hue value
10% BF
20% BF
30% BF
Values followed by the same letter in the same column are not significantly different (p < 0.05)
#Mean ± standard deviation (n = 4)
Table 4: Measurement of sensory evaluation for control and ultimate level of Banana Flour
(BF) – incorporated doughnuts*
10% BF
20% BF
30% BF
Colour of crumb
2.65 ± 1.06a
5.53 ± 1.42b
6.24 ± 0.90bc
7.00 ± 1.17c
Colour of crust
3.71 ± 1.21a
5.82 ± 1.13b
6.88 ± 1.05c
7.12 ± 0.99c
Moisture of crumb
5.94 ± 1.43a
5.53 ± 1.70a
5.29 ± 1.45a
5.59 ± 1.91a
Softness of crumb
5.12 ± 1.87a
6.12 ±1.36b
6.65 ± 1.06b
6.95 ± 1.17b
4.59 ± 1.50a
4.71 ± 1.60a
5.12 ± 1.70a
5.00 ± 1.70a
Banana flavour
2.71 ± 1.70a
4.29 ± 1.40b
5.24 ± 1.60b
5.24 ± 2.20b
Overall acceptability
5.00 ± 1.50a
5.65 ± 1.41ab
6.71 ± 1.40c
6.47 ± 1.50bc
Values followed by the same letter in the same column are not significantly different (p < 0.05)
* Mean ± standard deviation (n = 20)
is due to the lower gluten content in BF compared
Sensory evaluation results showed that the
to wheat flour. Gluten is an important component
incorporation of BF affected the colour of crumb
in protein which gives firmer dough matrix and
and crust as shown in Table 4. These results
manages to trap air cells to produce doughnuts
correspond with the results obtained from the
with greater volume.
instrumental colour measurement. Panel scores for
Ultimate increase in BF significantly (p < 0.05)
crumb softness decreased with increase in BF. This
affected the dough, crust and crumb colour (Table
decrease is due to the fact that BF is rich in starch
3) of doughnuts. Colour evaluation showed that
granules but lower in gluten content which results
the dough, crust and crumb of doughnut had hue
in doughnut with a harder and more compact
values which ranged from 68.97 – 88.76 (red –
structure. BF had no effect on the moisture of
yellow quadrant). Lightness (L*) values of dough,
crumb and sweetness of the doughnut. The banana
crust and crumb were noted to decrease with
flavour in BF-incorporated doughnuts was found
increasing level of BF in the doughnut
to be significantly higher (p < 0.05) than the
formulations. The decrease could be attributed to
control. Knuckles et al. (1997) reported that in
the higher amount of oxidized phenolic
sensory evaluation, products with score value of
compounds formed in the BF-incorporated
more than 5 for overall acceptability can be
doughnuts during the frying process. The darker
considered as a good quality product. Doughnut
colour of crumb for BF-incorporated doughnuts
with 20% BF was found to be the most acceptable
than the control was due to the more compact
and was significantly higher (p < 0.05) in score
structure of doughnut which resulted in less
value than the control and 10% BF-incorporated
reflection of light. The colour of the crust
contributed to the oil absorption effect and
Maillard reaction between protein and inverse
sugar in the presence of heat. Consequently, crust
L* values for the different types of doughnuts were
lower than that of the dough and crumb.
International Food Research Journal Vol. 15, 119-124

124 Chong, L. C. and Noor Aziah, A. A.
Hatae, K., Miyamoto, T., Shimada, Y., Munekata, Y., Sawa,
K., Hasegawa, K. and Kasai, M. 2003. Effect of the
Substitution of wheat flour with BF in doughnut
type of frying oil on the consumer preference for
indicated an increased in TDF content and can be
doughnut. Journal of Food Science, 68: 1038-1042.
classified as good fibre sources due to the
Ibadan, G.E., Heverlee, R.S. and Ibadan, S.A. 1992.
significantly higher dietary fibre content in the BF
Physicochemical studies on starches isolated from
doughnuts (10% BF : 5.51%, 20%BF: 6.56%,
plantain cultivars, plantain hybrids and cooking
30%BF: 6.89%) as compared to the control
bananas. Starch/Starke, 44: 121-128.
(3.07%). Doughnut with 20% BF was significantly
different (p < 0.05) in overall acceptability
Kachru, R.P., Nachiket, K. and Balasubramanian, D.
compared to the control and 10% BF doughnuts.
1994. Physical and mechanical properties of green
Therefore, acceptable doughnut can be prepared
banana (Musa paradisiacal) fruit. Journal of Food
by substituting wheat flour with 20% BF.
Engineering, 26: 369-378.
Kayisu, K., Hooh, L.F. and Vansoest, P.J. 1981.
Characterization of starch and fibre of banana fruit.
Journal of Food Science, 46: 1885-1890.
The authors wish to express their sincere gratitude
Kim, S.Y., Wiesenborn, D.P., Lorenzen, J.H. and
to The Malaysian Ministry of Science, Technology
Berglund, P. 1996. Suitability of edible bean and
and Innovation for funding this research.
potato starches for starch noodles. Cereal
Chemistry, 73 (3): 302-308.
Knuckles, B.E., Hudson, C.A., Chiu, M.M. and Sayre,
R.N. 1997. Effects of §-glucan barley fractions in
high-fiber bread and pasta. Cereal Food World, 42
AACC. 1984. Approve method. 8th edn. Washington D.
(2): 94-99.
C: American Association of Cereal Chemists
Approve Methods.
Krokida, M.K., Oreopoulou, V. and Maroulis, Z. B. 2000.
Water loss and uptake as a function of frying time.
AACC. 2000. Approve method. 10th edn. Washington D.
Journal of Food Engineering, 44 (1): 39-46.
C: Americsn Association of Cereal Chemists
Approve Methods.
Mellema, M. 2003. Review: Mechanism and reduction
of fat uptake in deep-fat fried food. Trend in Food
AOAC. 1990. Official method of analysis. 12th edn.
Science and Technology, 14 (9): 364-363.
Washington, D. C: Association of Official Analytical
Rehman, S., Paterson, A., Hussain, S., Murtaza, M.A. and
Mehmood, S. 2007. Influence of partial substitution
Braden, B.W. 1976. Yeast – raised doughnut. Proceedings
of wheat flour with vetch (Lathyrus sativus L) flour
American Society. Bakery Engineers: 127-131.
on quality characteristics of doughnuts.
Lebensmittel-Wissenchaft und-Technologie, 40 (1):
Chen, W.J.L. and Anderson, J.W. 1986. Hypocholestrol
effect of soluble fibre. In Vahouny, G.V. and
Kritchevsky, D.E. (Eds). Dietary Basic and Clinical
Suntharalingam, S. and Ravindran, G. 1993. Physical and
Aspect, p. 275 – 286. New York: Plenum Press.
biochemical properties of green banana flours.
Plant Food Human Nutrition (Dordrecth,
Collins, J.L. and Temalilwa, C.R. 1981. Cassava (Manihot
Neterlands), 43: 19-27.
esculenta Crantz) flour fortification with soy flour.
Journal of Food Science, 46: 1026-1028.
Watt, B.K. and Merrill, A.L. 1963. Composition of food.
Agriculture Handbook, 8, U.S. Department of
FAO. 2002. FAO Statistic Series. Yearbook Production,
Agriculture, Washington, DC.
47: 117. Rome: FAO.
FAO. 2003. FAOSTAT statistics database (last update May
2004). Agriculture. Rome,
International Food Research Journal Vol. 15, 119-214