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Journal of Animal Production Advances
Effect of Moisture, Extrusion Temperature and Screw Speed
on Residence Time, Specific Mechanical Energy and
Psychochemical Properties of Bean Four and Soy Protein
Aquaculture Feeds
Rodríguez-Miranda J., Delgado-Licon E.,Ramírez-Wong B., Solís-Soto A., Vivar-Vera M. A.,
Gómez-Aldapa C. A. and Medrano-Roldán H.
J Anim Prod Adv 2012, 2(1): 65-73
Online version is available on: www.grjournals.com

ISSN: 2251-7677
RODRIGUEZ-MIRANDA ET AL.
Effect of Moisture, Extrusion Temperature and
Screw Speed on Residence Time, Specific
Mechanical Energy and Psychochemical Properties
of Bean Four and Soy Protein Aquaculture Feeds
1 Rodríguez-Miranda J., *1 Delgado-Licon E., 2 Ramírez-Wong B., 1 Solís-Soto A., 3 Vivar-
VeraM.A., 4 Gómez-Aldapa C. A. and 1 Medrano-Roldán H.
Original Article
1 Graduate School of Biochemical Engineering, Postgraduate, Research and Development Unit, Technological Institute of Durango.
Blvd. Felipe Pescador 1830 Ote., Col. Nueva Vizcaya, C.P. 34080, Durango, Durango, México
2 Coordination of Graduate Food Science and Technology, Department of Food Research and Graduate (DIPA), University of Sonora,
Building 5-P, Blvd. Luis Encinas, Apto. Postal 1658, C.P. 83000. Hermosillo, Sonora México.
3 Graduate School of Biochemical Engineering, Postgraduate, Technological Institute of Tuxtepec, Av. Dr. Víctor Bravo Ahuja s/n
Col. 5 de Mayo. C.P. 68360, Tuxtepec, Oaxaca, México.
4 Chemical Research Center, ICBI–UAEH, Carr. Pachuca-Tulancingo Km 4.5 C.P. 42184, Mineral de la Reforma, Hidalgo, México.
Abstract
The aim of this study was to evaluate the effect of moisture supply, temperature and screw speed on
specific mechanical energy and functional properties of extruded feed for aquaculture bean flour and soy
protein. Fishmeal was replaced by different concentrations of bean flour or soy protein. Subsequently, the diets
were extruded and residence time, specific mechanical energy, absorption rate and solubility in water were
analyzed. Temperature and screw speed had a significant effect (P

EFFECT OF MOISTURE, EXTRUSION TEMPERATURE AND SCREW SPEED ON …
Introduction
Diets for rainbow trout (Oncorhynchus mykiss)
require a protein content of 29 to 50% and low
levels of starch (1-2%) (Kaushik and Medal, 1994;
Dabrowski, 1984, Uys and Hetcht, 1985, Charlton
and Bergot, 1986). Because of its high protein
content, grain legumes are widely used as a
replacement for fishmeal in fish diets (Allan, 1997).
The replacement of fishmeal for bean flower
(Phaseolus vulgaris L.) in the preparation of diets
for salmonid species has not been reported;
however, it is a good source of protein, and proves
to be cost effective compared to the use of other
plant sources such as soy, making it an attractive
replacement source alternative. Extrudates high in
vegetable protein must have the same quality, both
nutritional and functional, palatability and physical
properties as fishmeal-based extrudates (FAO,
2000). Therefore, aquaculture is undergoing a series
of technical developments for the improvement of
pellets, and the use of the extrusion processes to
improve the digestibility and the development of
high-energy food. Variations in the conditions of
the extrusion process (temperature, moisture content
and the addition of emulsifiers) have a significant
effect in the physicochemical properties of extruded
products, possibly by affecting the system’s specific
mechanical energy (SME) (Meuser et al., 1987;
Ollett et al., 1990, Hu et al., 1993). The SME is
responsible for the fragmentation of starch
molecules (Gomez and Aguilera 1983, 1984,
Davidson et al., 1984; Van Lengerich 1990, Wen et
al., 1990, Lai and Kokini 1991; Politz et al., 1994).
The residence time is considered a system
parameter that links the process variables such as
screw speed and moisture content. The residence
time of food during the extrusion process
determines the extent of chemical reactions and
ultimately the quality of products (Gogoi and Yam,
1994). The aim of this study was to evaluate the
effect of moisture supply, temperature and screw
speed on specific mechanical energy and
psychochemical properties of bean flour and soy
protein based extruded feed for aquaculture.
Materials and Methods
Experimental diet preparation
Fish flour based diets were elaborated with
different concentrations of bean flour and soy
protein (Table 1). The Pinto Saltillo bean
(Phaseolus vulgaris L.) was used for this study and
was obtained from the 2009 Spring-Summer harvest
produced at the Instituto Nacional de Investigación
Forestal, Agrícola y Pecuaria (INIFAP), Durango,
México. Soy protein was obtained from (Proteínas
de Calidad, México D.F., México) and fish flour
from (California Plant´s Choice, Ensenada Baja
California, México). The bean grains were milled
(BUHLER, S.P.A SEGRATE (MI) VIA RIVOLTA
2/D, BACILEA, Switzerland) and screened (U.S.A.
standard test sieve Astm E-11 Specification W.s.
Tyler, Made in U.S.A) at 0.5mm. Diets with partial
fish flour substitution were elaborated with 0, 15,
30, and 45% bean flour or a soy protein concentrate,
respectively. A total of seven diets were used for the
study; a control diet without vegetable protein
substitute (CD), substitution with 15% bean flour
(BF15), substitution with 30% bean flour (BF30),
substitution with 45% bean an flour (BF45),
substitution with 15% soy protein (SP15),
substitution with 30% soy protein (SP30),
substitution with 45% soy protein (SP45). Four
commercial balanced foods were also analyzed.
Extrusion Processing
A Brabender laboratory simple-screw extruder
(Model E 19/25 D, Instruments Inc South
Hackensack, NJ USA) was used to elaborate the
diets with the following characteristics: four heating
zones, screw compression force 1:1,
longitude/diameter relation (L/D) 20:1, internal
diameter of the exit die of 3 mm. Before extrusion,
a mixture of the formulate was performed as well as
the adjustment of humidity content to 18 to 22%
according to the experimental design. The samples
extruded were dried at 45 ºC for 20 h at 6%
humidity and stored in sealed polyurethane bags at
room temperature (25 ºC) for later analysis.
Experimental design and data analysis
A central design was composed with three
independent variables using a commercial statistical
software package (Design-Expert 8.0.2, Statease
Inc., Minneapolis, MN, USA). The independent
variables considered were the exit die temperature
66 J. Anim. Prod. Adv., 2012, 2(1):65-73

RODRIGUEZ-MIRANDA ET AL.
(X1), humidity content (X2), and the screw velocity
(X3) (Table 2). The response variables were:
Residence time (RT), specific mechanical energy
(SME), water absorption index (WAI) and water
solubility index (WSI).
Statistical Analyses
statistical package mentioned before. The results
were analyzed by way of multiple linear regressions
(Equation 1). The experimental data was adjusted to
the selected models and the regression coefficients
obtained. The statistical significance of the terms of
the regression was examined by using a variance
analysis (ANOVA) for each response.
The surface response methodology was applied
to the experimental data using the commercial
Table 1: Formulation and proximate composition of the test diets
Ingredients (g Kg -1 )
Diet
CD BF15 BF30 BF45 SP15 SP30 SP45
Fish meal 1 620 527 434 341 527 434 341
Bean flour --- 93 186 279 --- --- ---
Soy protein 2 --- --- --- --- 93 186 27.9
Wheat flour 200 200 200 200 200 200 200
Fish oil 3 120 120 120 120 120 120 120
Dried whey 4 34 34 34 34 34 34 34
Choline choride 5 5 5 5 5 5 5 5
Vitamin and mineral premix 6 20 20 20 20 20 20 20
Chromic oxide 7 1 1 1 1 1 1 1
Total 100 100 100 100 100 100 100
Proximate composition (%)
Dry matter 91.7 91.7 91.9 92.5 92.6 92.4 92.5
Crude protein (N x 6.25) 48.7 41.9 40.9 38.7 40.8 42.2 45.3
Crude fat 16.9 18.8 16.7 16.4 17.6 15.9 16.0
Ash 12.9 11.4 10.3 9.7 8.9 9.5 9.1
Nitrogen-free extractives 29.2 27.8 24.1 35.0 32.4 32.2 29.4
1 California Plant´s Choice, Ensenada Baja California, México. 2,3 Proteínas de Calidad, México D.F.,
México.4F&A Dariy products, Inc. Las cruces NM 88007 Product of The U.S.A. 5 Choline chloride
Sigma-Aldrich, Co., 3050 spruce street, St. Louis, MO 63103 USA. Reagent Grade ≥ 98%,
6 Composition of the vitamin and mineral premix: Ca,196 g/kg; P,46 g/kg; Na, 57 g/kg; NaCl, 111 g/kg;
Mg,12 g/kg; Fe,2.4 g/kg; Cu, 14 mg/kg; Mn, 1698 mg/kg; Se, 150 mg/kg; vitamin A, 4000,000,000 UI;
vitamin D3,40,000,000 UI; vitamin E, 400,000 UI, vitamin K, 160g/kg; vitamin B1, 61g/kg; vitamin B2,
160 g/kg; vitamin B6, 84g/kg; vitamin B12, 0.4 g/kg, folic acid, 4g/kg; calcium pantothenate, 540 g/kg,
7 Inert marker, chromic oxide, Sigma Chemical Co., St Louis, Mo, USA.
Table 2: Coded levels of extrusion cooking variables
Variable
Code
Levels
- α -1 0 +1 + α
Temperature (ºC) X 1 109.77 120 135 150 160.22
Feed moisture (%) X 2 16.63 18 20 22 23.36
Screw speed (rpm) X 3 59.54 80 110 140 160.45
α=1.682
Analysis
Residence time (RT)
67 J. Anim. Prod. Adv., 2012, 2(1):65-73
The residence time (RT) was measured
according to procedures described by Likimani
(1988). Distribution of rhodamine B red dye

EFFECT OF MOISTURE, EXTRUSION TEMPERATURE AND SCREW SPEED ON …
(Eastman Kodak Co., Rochester, NY) from a pellet
added to the feed served to measure residence time.
The mean residence time described the time where
half the extruded material had a residence time less
than the mean and the other half greater than the
mean.
Specific mechanical energy (SME)
The specific mechanical energy (SME) (J/g)
was calculated according to Harper (1981) and
Martelli (1983) as
(2)
Where Ω is the net torque exerted on the
extruder driver (N-m), ω in the angular velocity of
de screw (rad/sec) and mfeed is the mass flow
(g/min).
Water absorption index (WAI) and water
solubility index (WSI)
The water absorption index (WAI) and water
solubility index (WSI) were determined as outlined
by Anderson et al. (1969). One gram of ground
product was sieved at 0.420 mm and dispersed in 10
mL of water at room temperature (25±1 °C). The
resulting suspension was gently stirred for 30 min
and then the samples were centrifuged at 3000 x g
for 15 min (Hettich Zentrifugen EBA 12 D-78532,
Germany). The supernatant was decanted into a
tarred evaporating dish. The WAI was calculated as
the weight of sediment or gel obtained after removal
of the supernatant per unit weight of original solids
as dry basis. The WSI was the weight of dry solids
in the supernatant shown as a percentage of the
original weight of sample on a dry basis.
Materials and Methods
Residence time (RT) and specific mechanical
energy (SME)
Table 3 shows regression results for RT of all
diets. Diets showed significant regression models (p

RODRIGUEZ-MIRANDA ET AL.
and other geometric and texture features (Iwe et al.,
2001). The temperature in its linear form showed
regression coefficients with a negative effect (p

EFFECT OF MOISTURE, EXTRUSION TEMPERATURE AND SCREW SPEED ON …
the temperature from 120 to 150 ° C, decreases
WSI. This can be attributed to the fact that during
the extrusion process at high temperatures, starch
undergoes further degradation and can reach a
higher dextrinization, reducing the values of the
expansion radius, which is accentuated in mixtures
with low starch content (Chiang and Johnson 1977,
Colonna et al., 1984, Davidson et al., 1984;
Chinnaswamy and Hanna, 1987, Sacchetti et al.,
2005), as it is in this study. The negative regression
coefficients in the linear moisture of diets BF15,
BF30, PS15, PS30 and PS45 (Table 6) indicate that
increasing the humidity from 18 to 22%, decreases
WSI. This is probably due to an increase in the
percentage of polymerized starch during the
extrusion of high moisture content,which
diminishes protein denaturation and degradation of
starch. This results in lower WSI values (Chang et
al., 1998, Colonna et al., 1989, Hernandez-Diaz et
al., 2007) due to lower shear values applied caused
by the decrease in viscosity of the mixture. Proteins
can interact with starch through cross-linking (Goel
et al., 1999, Fernández-Gutiérrez et al., 2004). This
may prevent the solubilization of amylose, reducing
the WSI. A decreased WSI in the presence of the
protein has been also observed by Matthey and
Hanna (1997) and Hashimoto et al. (2002).
Conclusion
Our results show that the RT and EMS of
extruded diets for feed with bean flour and soy
protein replacement are affected significantly (p

RODRIGUEZ-MIRANDA ET AL.
Table 4: Regression equation coefficients of models (coded factors) for the specific mechanical energy (SME) of extruded
diets
Regression
Diet
Coefficients
CD BF15 BF30 BF45 SP15 SP30 SP45
Intercept 4.842* 7.383* 11.148* 7.441* 7.498* 8.177* 7.777*
Temperature (X 1 ) -1.018* -0.417* -0.725* -0.528* -0.597* -0.505* -0.419*
Moisture (X 2 ) 0.822 0.373* 0.410 0.185 0.180 0.247 0.172
Screw speed (X 3 ) 0.534 1.089* 1.527* 1.096* 1.203* 1.149* 1.128*
Temperature (X 2 1 ) 0.108 0.047 0.039 0.064 0.117 -0.256 -0.228
Moisture (X 2 2 ) 1.089* 0.169 0.327 0.191 0.138 -0.024 -0.114
Screw speed (X 2 3 ) -0.051 0.138 0.266 0.032 0.116 -0.096 -0.186
Temperature*moisture
(X 1 X 2 )
-1.021 -0.001 0.132 0.107 0.117 0.070 0.079
Temperature*screw
speed (X 1 X 3 )
0.508 0.054 -0.128 0.000 -0.001 -0.161 -0.155
Moisture*screw speed
(X 2 X 3 )
-0.002 0.383 0.328 0.125 0.096 0.026 0.060
R 2 0.84 0.92 0.94 0.91 0.90 0.90 0.96
Lack of fi 0.13 0.02 0.00 0.13 0.28 0.29 0.41
P 0.0660 0.0092 0.0045 0.0159 0.0184 0.0194 0.0014
*Parameter is significant to the predictive regression model (p < 0.05).
Table 5: Regression equation coefficients of models (coded factors) for the water absorption index (WAI) of extruded
diets
Regression Coefficients
Diet
CD BF15 BF30 BF45 SP15 SP30 SP45
Intercept 2.731* 2.029* 2.275* 2.096* 2.481* 2.220* 2.436*
Temperature (X 1 ) 0.020 -0.037 0.046 0.024 0.039 0.004 0.046
Moisture (X 2 ) -0.022 0.067 0.043 0.037 0.036 0.038 0.028
Screw speed (X 3 ) -0.042 -0.011 -0.016 -0.014 -0.044 -0.042 -0.002
Temperature (X 2 1 ) -0.050 0.016 0.003 -0.029 -0.041 0.016 -0.034
Moisture (X 2 2 ) -0.059 0.012 -0.018 -0.026 -0.006 0.043 0.017
Screw speed (X 2 3 ) -0.035 0.005 0.008 -0.039 -0.022 0.043 0.003
Temperature*moisture
(X 1 X 2 )
-0.051 0.013 -0.012 -0.011 0.002 -0.015 0.020
Temperature*screw
speed (X 1 X 3 )
0.019 0.028 0.007 -0.047 -0.013 -0.034 0.050
Moisture*screw speed
(X 2 X 3 )
0.028 -0.068 -0.020 0.009 0.016 -0.017 -0.001
R 2 0.69 0.61 0.60 0.53 0.54 0.70 0.42
Lack of fi 0.86 0.42 0.54 0.97 0.10 0.21 0.40
P 0.3151 0.5092 0.5104 0.6622 0.6559 0.3117 0.8452
*Parameter is significant to the predictive regression model (p < 0.05).
71 J. Anim. Prod. Adv., 2012, 2(1):65-73

EFFECT OF MOISTURE, EXTRUSION TEMPERATURE AND SCREW SPEED ON …
Table 6: Regression equation coefficients of models (coded factors) for the water solubility index (WSI) of extruded diets
Regression
Diet
Coefficients
CD BF15 BF30 BF45 SP15 SP30 SP45
Intercept 9.354* 10.455* 10.049* 10.346* 11.273* 15.045* 14.651*
Temperature (X 1 ) 0.419 -0.320 -0.378 -1.005* -0.230 -0.315 0.065
Moisture (X 2 ) -0.313 -0.605* -0.713* -0.272 -1.485* -1.731* -1.650*
Screw speed (X 3 ) 0.323 0.280 -0.069 0.031 0.025 -0.278 -0.192
Temperature (X 2 1 ) 0.219 -0.069 -0.409 -0.029 0.195 -0.470 -0.282
Moisture (X 2 2 ) -0.671 -0.724* -0.124 -0.065 -0.557 -1.204* -0.804*
Screw speed (X 2 3 ) -0.017 0.010 -0.082 0.095 -0.611 -0.632 -0.385
Temperature*moisture
(X 1 X 2 )
0.653 0.189 0.393 -0.881* -0.124 -0.400 0.068
Temperature*screw
speed (X 1 X 3 )
0.056 0.088 -0.254 -0.285 -0.612 0.551 -0.389
Moisture*screw speed
(X 2 X 3 )
-0.009 -0.314 0.003 -0.028 0.101 -0.491 0.020
R 2 0.70 0.81 0.76 0.81 0.87 0.89 0.88
Lack of fi 0.06 0.10 0.69 0.39 0.48 0.81 0.21
P 0.3052 0.0239 0.1790 0.1038 0.0455 0.0278 0.0305
*Parameter is significant to the predictive regression model (p < 0.05).
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