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ORIGINAL RESEARCH
Traditional Indian breakfast (Idli and Dosa) with
enhanced nutritional content using millets
Srinivasan KRISHNAMOORTHY, Singaravadivel KUNJITHAPATHAM and Loganathan MANICKAM
Department of Food Microbiology, Indian Institute of Crop Processing Technology, Ministry of Food Processing
Industries, Tamil Nadu, India
Abstract
Aim: To formulate ready-to-make millet mix Idli and Dosa, and to compare the chemical and sensory qualities of
those with pure rice mix Idli and Dosa.
Methods: Germinated powders of high-quality millets were mixed and incorporated with other basic traditional
ingredients like rice powder and de-husked black gram powder in formulated proportions. Nutritional and sensory
qualities were assessed after fermentation and cooking of the mix to make Idli and Dosa.
Results: The millet-based Idli contained high proportions of protein (15–18%), fat (5.0–6.2%) and carbohydrate
(72–74%) compared to the rice-based Idli. The ash content was in the range of 1–2% and crude fibre (3.0–4.9%). The
millet-based Dosa contained high proportions of protein (15–18%), fat (8.5–9.8%) and carbohydrate (69–72%)
compared to the rice-based Dosa. Also the processing steps like decortications, germination and fermentation
significantly reduced the phytic acids (69%) and tannin (78%) content in millet-based foods. The sensory evaluation
results showed that the overall acceptability of millet based product is ‘Like moderately’ with score of 7.7 ⫾0.5
Conclusion: The results indicated that the nutritional content of millet-incorporated Idli and Dosa was comparable
with the standard recommended dietary values, and the processing techniques not only decrease the antinutrients
but also enhance the essential nutrients. Emerging research on millet-based food is one of the strategies for
alleviating malnutrition.
Key words: antinutritional, fermentation, germination, millet, nutrition, rice.
Introduction
Good nutrition is very important in every stage of life. To
achieve good nutrition, it is important to learn more about
the sources and functions of nutrients. Energy has close
association with body weight. When our energy intake is
greater than energy output, body weight goes up. Therefore,
it is important to pay attention to the balance between
energy intake and output in order to maintain a healthy
body weight. Millets offer a cheap source of energy com-
pared to wheat and rice, and are widely consumed by rural
communities in many parts of the world to meet the micro-
nutrient requirements.1Millets such as pearl millet, finger
millet and sorghum are generally better providers of trace
minerals than cereals such as rice, maize and wheat.2
Maximum utilisation of the nutrient potential of the millet is
limited because of the presence of phytates, phenols,
tannins and enzyme inhibitors, but their effect can be
reduced by using processing techniques like popping, roast-
ing, malting and fermentation.3Development of ready-mix
with nutritious and light-weight precooked foods had been
receiving careful attention to meet the fast world needs.
Among the traditional fermented foods of South India,
Idli—a steamed rice cake with soft and spongy texture—and
Dosa—a rice-based crepe from fermented batter of rice and
lentil—were highly popular, and also consumed as breakfast
food. In order to overcome the problems faced in the
processing of the batter for Idli and Dosa and also the drudg-
ery associated with their preparation, ready-mixes have
been developed and made ready for commercial use. Fer-
mentation is one of the processes that decreases the level of
antinutrients in food grains. The antinutrional factors like
tannin and phytic acid interfere with the absorption of
calcium and iron by forming insoluble complexes. Millets
are particularly high in minerals like iron, magnesium,
phosphorous and potassium.4They are rich in proteins,
anti-oxidants, crude fibres, lipids, minerals and reducing
sugars. Finger millet (Ragi) is rich in calcium content, about
10 times that of rice or wheat. In traditional preparation of
Idli, millets are incorporated probably to improve the nutri-
S. Krishnamoorthy, MSc, Senior Research Fellow
S. Kunjithapatham, PhD, Professor
L. Manickam, PhD, Associate professor
Correspondence: S. Krishnamoorthy, Indian Institute of Crop
Processing Technology, Pudukkottai Road, Thanjavur—613 005,
Tamil Nadu, India. Email: srinigene@gmail.com
Accepted August 2012
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Nutrition & Dietetics 2013; 70: 241–246 DOI: 10.1111/1747-0080.12020
© 2013 The Authors
Nutrition & Dietetics © 2013 Dietitians Association of Australia
241
tional content, however there is no scientific evidence avail-
able. Therefore, the objective of the present study was to
develop and compare the nutrient composition of millet
based foods like Idli and Dosa which are suitable for easy
preparation with rice based foods.
Methods
Millets and rice of high quality were collected from local
markets. They were stored at room temperatures of 30° ⫾
5°C and humidity of 60 ⫾10%. About 200 g of millet grains
were soaked overnight in distilled water at room tempera-
ture. The seeds were placed on muslin cloth and continuous
watering was done for 48 hours for the seed to germinate.
The sprouted seeds were then dried at 60°C; the dried ger-
minated seeds were milled to obtain the germinated millet
flour. The millet mix powder was prepared by mixing equal
proportions of finger millet (Eleusine coracana), foxtail millet
(Setaria italica), proso millet (Panicum miliaceum), little millet
(Panicum sumatrense) and kodo millet (Paspalum orbiculare).
The mixture was stirred thoroughly and stored at room
temperature.
Idli and Dosa dry mix was prepared by mixing equal
proportions of rice (Oryza sativa) flour, millet mix flour
and de-cuticuled black gram (Vigna mungo) powder
(33 : 33 : 33). The ratio of rice and black gram for Idli dry
mix was standardised and the mix was allowed for fermen-
tation after mixing with two times water and 2% of salt.5
The fermented batter was used to prepare Idli by steaming in
the Idli mould vessel and Dosa by spreading over hot pan.
Prepared millet and rice-based Idli and Dosa were sub-
jected to sensory analysis based on a 9-point hedonic scale
for colour, taste, texture, flavour and overall acceptability
using a panel of 10 members who are familiar with the
product. Panel members were advised to use verbal descrip-
tions, and convert them into scores.6The scores were based
on the following criteria: like extremely: 9; Like moderately:
7–8; like slightly: 5–6; dislike slightly: 3–4; and dislike
extremely: 0–2. The scores were averaged and rounded to
the nearest whole number.
The cooked Idli and Dosa samples were analysed following
AOAC methods. Total nitrogen was determined according to
micro-Kjeldahl method.7Protein was calculated as N% ¥
6.25. Moisture content was determined by drying samples at
103°C for 4 hours in hot air oven and then dry matter was
calculated as per AOAC official method 945.15. Crude fibre
content was determined by acid/alkali digestion.8Total fat
was extracted with hexane using the Soxhlet apparatus
according to the AOAC Official Method.7Total carbohydrate
was estimated by phenol sulphuric acid method. Phospho-
rus was determined by the ammonium molybdate/
ammonium vanadate method.9Calcium was determined by
the titration method.10 Iron in the sample was estimated by
spectrophotometric analysis method.11 The energy density of
the millet mix and rice-based food products were then cal-
culated using Atwater coefficients: 4 kcal/g for protein and
available carbohydrates and 9 kcal/g and 3 kcal/g for dietary
fibre.
The antinutritional factors like phytic acid and tannin
were estimated from millet mix powders without any
processing and also after processing like decortications and
fermentation. The phytic acid was determined.12 The tannin
content of millet flour was determined by adopting the
modified vanillin-HCl method.13 The experimental data
were analysed using Student’s t-test at 5% level of
significance.
The cost of the millet-based and rice-based food items
were estimated on the basis of the cost of raw ingredients of
the products and preparation. In the economic point of view,
the costs were compared and the data were discussed.
Results
The nutrient composition of Idli (per 100 g cooked food
sample) prepared from millet-based and rice-based mix was
analysed and compared (Table 1). The results showed that
moisture content of Idli from millet-based and rice-based
mix was 67 and 65%, respectively. There was no significant
difference at 5% level.
The protein content was high in millet mix Idli with 15.1
⫾2.09 g/100 g in comparison with rice Idli (7.2 ⫾1.10 g).
A least fat content of 0.84 ⫾0.35 g was seen in rice Idli in
comparison to millet mix Idli of 5.2 ⫾0.28 g. With respect
to ash content, millet mix Idli had higher ash content of 1.69
⫾0.06 g and rice Idli had the ash content of 1.59 ⫾0.02 g
(Table 1). As millets contain higher fibre, its incorporation
showed increased level of fibre content in millet mix Idli with
3.8 ⫾0.05 g and lower crude fibre of 1.08 ⫾0.03 g in rice
Idli. The carbohydrate content was highest in rice Idli (75.6
⫾0.95 g) and slightly lower in millet mix Idli (72 ⫾0.55 g).
The energy content was highest in millet mix Idli (424 ⫾
0.18 kcal) and least was found in rice Idli (328 ⫾0.19 kcal).
The calcium content was 128 ⫾0.66 mg in millet mix Idli
compared to rice Idli (69 ⫾0.12 mg). Iron content was also
higher in millet mix Idli (3.40 ⫾0.06 mg). The higher
calcium and iron content in the millet mix products might be
due to the addition of finger millet in the preparation in
addition to black gram and other cereals. Statistically, there
was a significant difference in the nutrients among the millet
mix Idli and rice Idli.
The nutrient composition of Dosa (per 100 g of cooked
food sample) prepared from millet-based and rice-based mix
was compared (Table 2). The results showed that moisture
content of Dosa from millet-based and rice-based mix were
26.82 ⫾0.10 and 27.52 ⫾0.11%, respectively. The protein
content was higher in millet-based Dosa with 13.8 ⫾0.15 g
against rice-based Dosa 6.6 ⫾0.25 g. This might be due to
higher protein content of millets and similar results were
reported earlier.14 Also, the increase in protein content can
be attributed to microbial synthesis of proteins from meta-
bolic intermediates during their growth cycles.15 The fat
content of millet mix Dosa and rice Dosa were 9.8 ⫾0.10 g
and 1.96 ⫾0.26 g, respectively. With respect to ash content,
millet mix Dosa had the highest ash content of 2.85 ⫾0.15 g
and rice Dosa had ash content of 2.09 ⫾0.12 g. As millets
S. Krishnamoorthy et al.
© 2013 The Authors
Nutrition & Dietetics © 2013 Dietitians Association of Australia
242
Table 1 Nutritional content of millet-based Idli and rice-based Idli
Food products
Nutrient composition (wet basis)
Moisture (%) Protein (g) Fat (g) Ash (g) Crude fibre (g) Carbohydrate (g) Calcium (mg) Iron (mg)
Ascorbic
acid (mg) Energy (kcal)
Millet mix Idli 61.80 ⫾1.58 15.1 ⫾2.09 5.2 ⫾0.28 1.69 ⫾0.06 3.8 ⫾0.05 72 ⫾0.55 128 ⫾0.66 3.40 ⫾0.06 3.1 ⫾0.04 424 ⫾0.18
Rice Idli 62.20 ⫾0.15 7.2 ⫾1.10 0.84 ⫾0.35 1.59 ⫾0.02 1.08 ⫾0.03 75.6 ⫾0.95 69 ⫾0.12 1.96 ⫾0.12 1.8 ⫾0.02 328 ⫾0.19
The results represent the mean ⫾standard deviation of the analysis performed. Values are significantly different at P<0.05 (n =5).
Table 2 Nutritional content of millet-based Dosa and rice-based Dosa
Food Products
Nutrient composition (wet basis)
Moisture (%) Protein (g) Fat (g) Ash (g) Crude fibre (g) Carbohydrate (g) Calcium (mg) Iron (mg)
Ascorbic
acid (mg) Energy (kcal)
Millet mix Dosa 26.82 ⫾0.10 15.8 ⫾1.15 9.8 ⫾0.10 2.85 ⫾0.15 3.95 ⫾0.02 69 ⫾0.20 114 ⫾0.52 3.42 ⫾0.16 2.8 ⫾0.12 429.8 ⫾0.14
Rice Dosa 27.52 ⫾0.11 6.6 ⫾0.25 1.96 ⫾0.26 2.09 ⫾0.12 1.43 ⫾0.01 73.4 ⫾0.82 74 ⫾0.52 1.8 ⫾0.26 2.2 ⫾0.02 342 ⫾0.24
The results represent the mean ⫾standard deviation of the analysis performed. Values are significantly different at P<0.05 (n =5).
Development of millet-based breakfast items
© 2013 The Authors
Nutrition & Dietetics © 2013 Dietitians Association of Australia
243
contain high fibre, its incorporation showed higher fibre
content of 3.95 ⫾0.02 g in millet mix Dosa, whereas rice
Dosa contains 1.43 ⫾0.01 g. The carbohydrate content was
more in rice Dosa (73.4 ⫾0.82 g) compared to millet mix
Dosa (69 ⫾0.20 g). The energy content in millet mix Dosa
was 429.8 ⫾0.14 kcal, but in rice Dosa, it was 342 ⫾
0.24 kcal, which could be due to variations in quantity of oil,
pulses and millets in the product.
The calcium content of the millet- and rice-based Dosa
were 114 ⫾0.52 mg to 74 ⫾0.52 mg, respectively. Iron
content was highest in millet mix Dosa with 3.42 ⫾0.16 mg.
However, rice Dosa had 1.8 ⫾0.26 mg of iron. Statistically,
there was a significant difference in the nutrients among the
millet mix and rice products.16
The initial tannin and phytic acid content were 3.42 ⫾
0.95 and 875.1 ⫾16.35 mg/g, respectively. In germina-
tion, the tannin content was reduced by 66.1% and phytic
acid reduced by 45.3% only (Figure 1), where as fermen-
tation causes reduction of 55 and 64% respectively. The
maximum reduction of 72.2% of tannin and 81.2% of
phytic acid were found after the cooking process.17 The
decrease in phytic acid and tannin content is consistent as
reported earlier that the phytase activity during fermenta-
tion of bread dough causes degradation of the phytic
acid.18 Heat degradation, leaching out effects, change in
chemical reactivity and formation of insoluble complexes
might be the factors that resulted in the significant reduc-
tion of these antinutrients by cooking.19 Germination
decreased the tannin and phytic acid content. The tannin
content of fermented millets obtained in the study is
similar to the results of Ramachandra et al.20
The sensory evaluated results showed that the colour of
millet mix Idli was 7.0 ⫾0.5 (like moderately), but the
overall acceptability of data on sensory quality obtained by a
panel of ten members showed that both millet mix and
rice-based Idli/Dosa was ‘Like Moderately’ and ‘Like
Extremely’, respectively (Tables 3,4).
The costs of the millet-based and rice-based Idli and Dosa
were calculated on the basis of the cost of raw ingredients.
The cost of millet-based Idli and Dosa mix is Rs 20/kg
(0.38 AUD/kg), whereas for the rice-based Idli and Dosa mix,
it is of Rs 32/kg (0.61 AUD/kg). Since the preparation was
similar, the cost of preparation is not included for the
comparisons.
Figure 1 Percentage reduction of antinutritional factors (tannin and phytic acid) after germination, fermentation and cooking
of millet mix Idli.
Table 3 Sensory quality characteristics of millet mix Idli and rice Idli
Quality
Millet mix Idli Rice Idli
HS SCM HS SCM
Colour 7.0 ⫾0.5 Like moderately 9 ⫾0.2 Like extremely
Taste 8.0 ⫾0.3 Like moderately 8.5 ⫾0.1 Like moderately
Flavour 7.0 ⫾0.6 Like moderately 7.5 ⫾0.3 Like moderately
Texture 6.5 ⫾0.4 Like slightly 8.5 ⫾0.1 Like moderately
Appearance 8.0 ⫾0.5 Like moderately 8.0 ⫾0.4 Like moderately
Overall acceptability 7.7 ⫾0.5 Like moderately 9.0 ⫾0.2 Like extremely
* Average of ten panel members.
Statistical significance paired t-test; 0.05 >*P>0.01.
HS, Hedonic Scale; NS, Not Significant; SCM, Score Card Method.
S. Krishnamoorthy et al.
© 2013 The Authors
Nutrition & Dietetics © 2013 Dietitians Association of Australia
244
Discussion
The findings indicated that the moisture content of Idli from
millet-based and rice-based mix was 67 and 65% (wet
weight basis), respectively. Incorporation of millets at 50%
level to the rice did not affect the moisture content of food
items. It is evident that the protein content was high in millet
mix Idli compared to rice Idli. This might be due to higher
protein content of millets as well as fermentation which
causes to increase the availability of protein content.21 Simi-
larly, a least content of fat was seen in rice Idli in comparison
to millet mix Idli. It is observed that the fibre content of
millet incorporated food items showed high fibre content.
The carbohydrate content was highest in rice Idli compared
to millet mix Idli. Presence of rice which is rich in starch
might be a contributing factor for high carbohydrate
content. The calculated total energy content was more in
millet mix Idli compared to rice Idli, which could be due to
multi-nutrient content of millets in the product. Millet mix
products had higher calcium content among the products.
This may be due to the addition of finger millet in the
product preparation other than black gram and other
cereals.
In the present study, a similar trend could be observed in
nutritional analysis data of Dosa and Idli. The moisture
content of Dosa prepared from millet-based and rice-based
mix was not significantly different. The protein, fibre, ash,
total carbohydrates and total energy content of millet incor-
porated Dosa were at higher levels compared to rice-based
mix. The antinutritional factors found in millet mix flours
decreased to traceable amount after the processing like ger-
mination, decortication, fermentation and cooking. The
study has also demonstrated that the fermentation can sig-
nificantly reduce the antinutritional factors like phytic acid
content of ready-mix Idli and Dosa, and also enhance the
acceptability of the product.
The sensory results showed that the texture and appear-
ance of the millet incorporated food items were acceptable as
assessed by the panellists. Most of the traditional recipes can
be prepared by incorporating millets without affecting the
sensory quality but increasing the nutritional quality of the
products. Thus, millet-based Idli and Dosa have higher nutri-
ent levels than that of the rice-based Idli and Dosa. The raw
materials for millet-based traditional products are readily
available in the market, and the product possesses higher
nutritional status and is cost-effective. Protein malnutrition
and metabolic disorders like diabetes can be tackled more
efficiently and successfully by incorporating millets with rice
which are equally nutritious like any other traditional cereal
or pulse in daily dietaries. The research on the incorporation
of germinated millets in ready-to-use Idli and Dosa mixes
was undertaken to explore the inherent technological oppor-
tunities for better utilisation of millets in designing value-
added and functional foods in different sectors of food
industries.
Acknowledgement
The authors are grateful to Dr. K. Alagusundaram, Director,
Indian Institute of Crop Processing Technology, Thanjavur
for his constant encouragement. We also wish to thank the
editors and referees for their helpful comments and sugges-
tions which greatly improved the paper.
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Table 4 Sensory quality characteristics of millet mix Dosa and rice Dosa
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Development of millet-based breakfast items
© 2013 The Authors
Nutrition & Dietetics © 2013 Dietitians Association of Australia
245
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246