UTILIZATION OF PULSE FLOURS IN THE
DEVELOPMENT OF HEALTHIER FOODS
www.cigi.ca
P. Frohlich, A-S. Bellido, G. Boux and L. Malcolmson, Canadian International Grains Institute (CIGI), Winnipeg, MB
Protein3 (%) 23.7 27.0 21.8 Total Dietary Fibre3 (%) 12.1 9.6 11.4 Total Starch3 (%) 51.3 48.5 39.1 Colour - a*4 3.5 0.5 1.3 Colour - b*5 33.6 39.7 30.92 Value taken from Canadian Nutrient File
2
Value taken from Bunge Milling Inc.
3
Values based on dmb
4
a* - greenness (-) to redness (+)
5
b* - blueness 9 (-) to yellowness (+) 15.8 3
71.5 -2.6 24.17 Corn meal
(Extrusion)
Durum
Semolina
(Pasta)
Chickpea
Flour
Green Lentil
Flour
Yellow Pea
Flour
Canada produces more than 5.0 million tonnes of pulses per year
of which approximately 85% are exported to 150 countries around
the world. Saskatchewan is the largest producer of peas, lentils
and chickpeas making up approximately 90% of Canada’s total
pulse exports. The majority of Canadian pulse exports are shipped
to global markets where they form an important protein and
energy staple in local diets. The low consumption of pulses in
Canada can be attributed to a lack of consumer awareness of the
health benefits of pulses and knowledge of how to use pulses in
the diet. By investigating the behaviour of pulse flours in cerealbased products there is an opportunity to develop healthier foods
for today’s health conscious consumer.
11.9 7.02
3.11 2.02
73.21 77.72
0.7 -0.7
40.06 13.23
Tortillas with 25% green lentil flour had a lower a* (red) value than the other tortillas including the 100% wheat flour control tortillas (Table 3, Figure 4).
There was an overall decrease in quality (measured by tortilla diameter, thickness and rollability) of tortillas made from pulse flours compared to the control tortillas (Table 3). Tortillas made from green lentil flour had the poorest quality.
The protein and total dietary fibre contents of the 25% pulse flour blends increased and total starch decreased compared to the 100% refined wheat flour.
To compare the quality of pasta, tortillas and extruded
products made from yellow pea, chickpea, and green lentil flours to products made with conventional ingredients. To determine if the pulse products offered improved nutritional properties and maintained acceptable quality characteristics.
Table 3. Quality Parameters of Tortillas.
Figure 1. Particle Size Distribution of Wheat and Pulse Flours.
MATERIALS AND METHODS
Colour Diameter Thickness
a*1 (cm) (mm) Rollability2
Control (100% Wheat Flour) -0.7 Chickpea Flour
25% Yellow Pea Flour
25% Green Lentil Flour
25% 20.9 2.44 1.0
-0.476 18.9 3.36
1.8
0.34 18.7 3.42
2.2
-1.42 19.8 3.64
3.6
a* - greeness (-) to redness (+)
2
Rollability scores where: 1=no sign of cracking/good rollability and 5=severe
cracking/not able to roll
1
Pulse Flours, Wheat Flours and Corn Meal
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OBJECTIVE
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Tortillas
Table 1. Proximate Analysis of Flours.
Refined
Wheat Flour
(Tortillas)
INTRODUCTION
Yellow peas, Kabuli chickpeas and green lentils were processed using CIGI’s pilot scale dehulling and splitting equipment. The dehulled and split pulses were milled into flour using a
Jacobson bench top hammer mill.
Refined wheat flour was produced from CPSR wheat using
CIGI’s Buhler pilot scale flour mill.
Durum semolina and corn meal were acquired from commercial suppliers.
Figure 4. Tortillas Made With 100% Refined Flour,
25% Chickpea Flour, 25% Yellow Pea Flour and 25% Green
Lentil Flour.
Figure 2. Chickpea, Yellow Pea and Green Lentil Flours.
Flour Analysis
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Protein (Williams et al., 1998), total starch (AACC 76-13), total dietary fibre (AOAC 991.43) and colour (Minolta CR-310, wet slurry AACC 14-30) were determined on the flours.
Flour particle size distribution was measured by sifting 100 g of flour through a Buhler lab sifter equipped with 7 sieves of varying mesh sizes. Pasta
Blends were prepared by mixing several levels of pulse flours (10,
20 and 30%) with durum semolina. The blends were used to make
spaghetti with a Namad laboratory pasta extruder. Pasta was
dried using an 85OC commercial drying cycle. Pasta colour was
determined on dried spaghetti using a Minolta CR-310
colorimeter. Cooking time was defined as the time in minutes
required for the centre core in the strands to disappear. Texture of
the cooked spaghetti was determined using a TA.HD plus texture
analyzer equipped with a pasta blade and plate. Firmness was
defined as the amount of force required to shear through ten
strands of cooked pasta.
Tortillas
Blends of 25% pulse flours with 75% refined CPSR wheat flour
were used to prepare tortillas from a commercial formulation in
CIGI’s pilot bakery. Thickness, diameter, and rollability were
measured on the baked tortillas. Extruded Products
Extruded snacks were prepared on CIGI’s Clextral EV-25 pilot twin
screw extruder using 100% pulse flours. Bulk density and
expansion ratio measurements were used to assess the physical
attributes of the extrudates.
Extruded Products
Spaghetti
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As the level of pulse flour increased in the spaghetti there was a corresponding increase in a* (red) values (Table 2, Figure 3).
All spaghetti made with pulse flours had similar cooking times but all were lower than the 100% durum semolina control
spaghetti (Table 2).
Cooked spaghetti made with pulse flours was firmer than the control spaghetti (Table 2). As the level of pulse flour increased there was a corresponding increase in firmness especially for the spaghetti made from yellow pea and green lentil flour. As the level of pulse flour increased so did the protein and
fibre contents of the spaghetti flours. With increasing levels of pulse flours the total starch content of all spaghetti flours decreased.
Colour a*1 Shear Force (N) Cooking
Time
(min)
0.4 9.43 12:07
10% 20% 30% 0.72 9.48 16.21 11.73 12.25 11.0 11:00
10:30
11:15
10% 20% 30% 6.03 13.72 18.38 11.09 11.93 14.4 11:00
10:48
10:30
20% 30% 5.48 11.61 17.34 11.0 12.8 15.16 11:30
11:30
10:45
Control (100% Durum Semolina) Chickpea Flour
Yellow Pea Flour
RESULTS
Green Lentil Flour
10% Pulse Flours
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All pulse flours had higher protein concentrations than durum semolina, refined wheat flour and corn meal (Table 1). Green lentil flour had the highest protein content of all flours.
Yellow pea flour exhibited the highest total starch and dietary fibre contents among the pulse flours (Table 1). Green
lentil flour was lower in fibre while chickpea flour had the least total starch.
Pulse flours had similar particle size profiles to each other
(Figure 1). As expected, durum semolina and corn meal had the largest particle size profiles and refined wheat flour had the
smallest particle size profile.
Green lentil flour had the highest b* (yellow) value followed by yellow pea and chickpea flours. Yellow pea flour had the highest a* (red) value followed by chickpea and green lentil flours
(Table 1, Figure 2).
a* - greenness (-) to redness (+)
1
Figure 3. Spaghetti Made With 100% Durum Semolina
(Control) and 10%, 20%, 30% Pulse Flours.
Control
10%
Chickpea
Yellow Pea
Green Lentil
20%
Extrudate made from yellow pea flour had a similar expansion ratio and bulk density to the control extrudate made from 100% corn meal. The extrudate made from chickpea flour had the
lowest expansion ratio and the highest bulk density (Table 4, Figure 5).
The extrudates made from pulse flours had higher protein and total dietary fibre content than the control extrudate (Table 1).
Table 4. Quality Parameters of Extruded Products.
Expansion
Bulk Density
Ratio (g/cm3)
Control (100% Corn Meal) 30%
3.31
0.09 Chickpea Flour 100%
1.36
0.54
100%
2.81
0.09
100%
2.07
0.3
Yellow Pea Flour
Table 2. Quality Parameters of Spaghetti.
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Green Lentil
Figure 5. Extruded Products Made With 100% Corn Meal,
100% Yellow Pea Flour, 100% Green Lentil Flour and
100% Chickpea Flour.
1 cm
CONCLUSIONS
Research at CIGI has shown that durum semolina could be partially
substituted with various pulse flours in spaghetti formulations to
enhance their nutritional properties causing minimal effects to their
quality. Similarly, chickpea and yellow pea flour could partially
replace refined wheat flour in tortilla formulations. The use of 100%
yellow pea and green lentil flours resulted in a high quality extruded
product similar to conventional extruded products available in the
market. In addition, the extruded pulse products exhibited higher
protein and dietary fibre content. Overall, expanding the use of pulse
ingredients in foods will diversify the markets for Canadian pulses
and increase value-added opportunities.
ACKNOWLEDGEMENTS
Funding for this project was provided by the Saskatchewan Pulse
Growers and the Manitoba Pulse Growers Association. The
technical assistance of CIGI’s Analytical Services staff E. Sopiwnyk,
D. An, and R. DeStefano and CIGI’s Pasta and Extrusion Technology
staff P. Ebbinghaus is greatly appreciated. Special thanks to
A. Medwid for poster design and layout.