IJFS#1706_bozza


	

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PAPER 
 
 
 
 
 

BROMATOLOGICAL COMPOSITION AND EFFECT 
OF TEMPERATURE ON THE RHEOLOGY 

OF EGGPLANT PULP 
 
 
 
 
 
 
 

R. MARSIGLIA1, L. MIELES-GÓMEZ, S. LASTRA, S.E. QUINTANA 
and L.A. GARCÍA-ZAPATEIRO* 

Faculty of Engineering, Food Engineering Program, Research Group in Complex Fluids Engineering 
and Food Rheology (IFCRA), University of Cartagena, 130015 Cartagena, Colombia 

*Corresponding author: lgarciaz@unicartagena.edu.co 
 
 
 

ABSTRACT 
 

This study aimed to determine the bromatological composition and the behavior of 
rheological parameters on the pulp eggplant (Solanum melongena). Bromatological analyzes 
were performed according to the reference methods, in which a percentage of  
moisture 90.98%, total carbohydrates 6.86%, crude fiber 1.94%, crude protein 1.19%, Fat 
0.31% and 0.49% of ash has been obtained. Viscous flow curves were calculated in the 
steady state over a temperature range of 10-80ºC, and the rheological properties of the 
pulp were evaluated as a function of temperature. The pulp showed pseudoplastic 
behavior (shear thinning type) at all temperatures, and the relationship between viscosity 
and the Carreau-Yasuda model (R2>0.99). The Arrhenius equation was fitted to the data 
for the apparent viscosity of the pulp with respect to temperature, with activation energy 
E𝑎=1081.61 J/mol. The results provide information on bromatological composition and the 
rheological behavior of eggplant pulp and may have applications in the design of 
processes using this raw material. 
 
 

Keywords: Carreau-Yasuda model, eggplant (Solanum melongena), bromatological analysis, pulp, 
rheological behavior, shear thinning 



	

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1. INTRODUCTION 
 
Eggplant or aubergine (Solanum melongena) is an economically important crop that is 
widely cultivated in tropical and subtropical areas of the world, and its cultivars produce 
a wide variety of fruits with different shapes, sizes and colors (SALUNKHE and DESAI, 
1984; SAN JOSÉ et al., 2013; NIÑO-MEDINA et al., 2017). The global consumption of 
eggplant has increased in recent years, due to the numerous benefits of this crop, such as 
the presence of metabolites that contribute significantly to a healthy diet (SUN et al., 2015). 
It has also been found that extracts of eggplant can successfully suppress the development 
and growth of tumors, metastasis, inflammation and heart disease (NISHA et al., 2009). 
Eggplant is one of the vegetables on which great importance is placed in the Colombian 
Caribbean, due to its strong suitability for export, the aforementioned health benefits, its 
high content of phenols and antioxidant activity, and its contribution to the diet in terms 
of low calorie content, very low sodium content and high fiber content (ARAMENDIZ-
TATIS et al., 2010). 
According to Food and Agriculture Organization - FAO (2015) data from 2015, eggplants 
used for consumption were fresh (more common), or in industrial processes, mainly 
frozen. In industrial processes, this vegetable can be used as cubes or dice, such as in 
slices, jams and jellies. The products of fruits and vegetables contain pulps as basic raw 
materials, which in most cases are transported via pipes and tanks and are agitated and 
mixed with other raw materials, pasteurized and evaporated in heat exchangers and 
continuous evaporators. In addition, other operations are applied such as sieving, 
snubbing, mixing and various thermal treatments. In order for these operations to be 
technically and economically feasible, it is important to have a knowledge of the 
properties of the pulp (IBARZ et al., 1996; ORTEGA-QUINTANA et al., 2015). 
The rheological behavior is one of the most important properties in the development of 
new products, and is very useful in the design of unit operations, guarantees of high-
quality food and beverages, and process optimization. In addition, rheological approaches 
are essential tools for food engineering, since rheology is linked to the processing and 
stability of food as well as its sensory qualities. Physical properties such as density, 
specific heat and thermal conductivity are of great importance for food and beverages, as 
they are closely related to their sensory and rheological characteristics (AUGUSTO et al., 
2012; DE CASTILHOS et al., 2017). 
Several factors affect the rheological behavior of fruit and vegetable pulps, and 
temperature is the most likely to affect the viscosity of the pulp (HOLDSWORTH, 1971). 
An understanding of the influence of temperature on viscosity is therefore fundamental in 
obtaining better knowledge of the rheological behavior of fruit and vegetable derivatives 
during processing at high temperatures (IBARZ et al., 1996). 
Various studies have been carried out on the rheological behavior of pulps from different 
botanical sources; most of these do not comply with Newton's law of viscosity, and it is 
said that they behave like non-Newtonian fluids. Their behavior can be described by a 
power law (HOLDSWORTH, 1971) or by the Herschel-Bulkley model in the case where 
they have a non-zero yield stress (STEFFE, 1996). The main objective of this research is to 
determine the effect of temperature on the behavior of the rheological parameters of 
eggplant pulp. 
 
 
 
 



	

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2. MATERIALS AND METHODS 
 
The eggplants used were acquired from a food supply center in Cartagena, Bolivar-
Colombia, and were in a state of commercial maturity and free from mechanical damage.  
 
2.1. Pulp extraction 
 
The selected fruits were weighed, washed and blanched at 80ºC for five minutes. Pulp was 
obtained using a refining 1.5 mm opening mesh, giving a pulp to facilitate rheological 
measurements. This was then packed in hermetic bags and stored in refrigeration at 4ºC 
for 24 hours for further rheological analysis. 
 
2.2. Bromatological evaluation 
 
Bromatological analyses were performed on the eggplant pulp. Moisture content, ash, 
protein, fat, total carbohydrates and raw fiber were determined using the methods 
described by the Association of Official Analytical Chemists (AOAC) (2000): moisture: 
Dehydration in an oven at 105ºC AOAC 33.7.03 Method 926.08; ash: y combustion at 450ºC 
for 12 hours AOAC 33.7.07 Method 935.42; crude protein: Using the method of Macro 
Kjeldahl, AOAC 33.7.12 Method 926.123; fat: AOAC 972.28 ethereal extraction method; 
total carbohydrates: AOAC 923.03; Crude fiber: A.O.A.C. 985.29. 
 
2.4. Rheological evaluation 
 
Steady flow tests were carried out to give viscosity curves at temperatures of 10ºC, 20ºC, 
25ºC, 40ºC, 60ºC and 80ºC for samples without a previous history of shear, using a 
controlled-stress rehometer (Modular Advanced Rheometer System Mars 60, Haake, 
Thermo-Scientific, Germany), equipped with Peltier temperature control and measuring 
system, using a stainless steel plate-plate geometry (rough surface Ø 35 mm) with 1 mm 
gap, over a range of shear rates between 0.001 and 1000 s-1 (Franco et al., 1998). Prior to 
measurement, all samples were left at rest for 600 s to allow for relaxation, and the 
temperature of the samples was kept constant at 20±0.1°C using a Peltier system, 
following the methodology used by QUINTANA et al. (2017). 
 
2.4. Statistical analysis 
 
The data were analyzed with a unidirectional ANOVA using SPSS software (version 17.0 
for Windows) in order to determine statistically significant differences (p < 0.05) between 
the samples. All tests were performed in triplicate. 
 
 
3. RESULTS AND DISCUSSION 
 
3.1. Bromatological analysis 
 
Table 1 shows the average values for moisture, total carbohydrates, total fiber, protein, fat 
and ash, obtained in triplicate. The results show that the eggplants used in this study 
mostly contained water at a percentage of 90.98±0.016%, a carbohydrate content of 



	

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6.86±0.17% and a fiber content of 1.94±0.07%, fairly close to the values reported by 
GARCÍA et al. (2003), MOREIRAS et al. (2013) and ICBF (2015). 
 
 
Table 1. Bromatological analysis. 
 

Sample (%) Moisture Total carbohydrates Crude fiber Crude protein Fat Ash 
Eggplant 90.98±0.16 6.86±0.17 1.94±0.07 1.19 ±0.04 0.31±0.02 0.49±0.02 

 
 
Eggplant represents an important source of dietary fiber, and therefore has health benefits 
in terms of its effects on digestive regularity and the prevention of diseases such as 
constipation, hypercholesterolemia, hyperglycemia and obesity, which are partly related 
to intake of fiber (ALVES DOS SANTOS et al., 2002). Its beneficial physiological effects lie 
in its texture and consistency, since it acts as a sponge that binds to foods rich in 
cholesterol, releasing accumulated wastes from the intestinal wall, which would otherwise 
be difficult to expel. It also increases the fecal mass, which results in a reduction in 
carcinogenic risk and faster elimination from the body (CAÑAS-ÁNGEL et al 2011.) 
 
3.2. Rheological evaluation 
 
The variation of the viscosity with the deformation speed was observed using steady flow 
tests at different temperatures. Fig. 1 shows the viscous flow curves for the eggplant pulp 
as a function of the deformation speed, at temperatures of 10°C, 20°C, 25°C, 40°C, 60°C 
and 80°C. These curves show the characteristics of a non-Newtonian fluid of 
rheofluidifying (shear thinning) type, since they combine the characteristic properties of 
elastic and both solid-like and liquid-like properties, characterized by a potential decrease 
in viscosity with respect to the shear rate (MULLER, 1973). On the other hand, a constant 
viscosity value 𝜂!  and at high deformation 𝜂!  velocities are observed at low deformation 
speeds. 
This behavior can be explained by the breaking of the reticular structure of polysaccharide 
molecules during shearing, as explained by BHANDARI et al. (2002). In a reticular system, 
the speed at which existing molecular interactions break becomes higher than the speed at 
which they reform, with increasing shear rate. The result is a lower intermolecular 
resistance to the flow, and hence a lower viscosity (DÍAZ-OCAMPO et al., 2012). Similar 
behaviors have been observed in several fruit pulps, such as squash pulp (Cucurbita 
moschata) (QUINTANAa et al., 2018); papaya pulp (Carica papaya) (QUINTANA et al., 2017); 
borojó pulp (Borojoa patinoi cuatrec) (DÍAZ-OCAMPO et al., 2012); nispero pulp (Achras 
sapota L.) (ANDRADE et al., 2009) and mango, papaya and peach purees (GUERRERO and 
ALZAMORA, 1998). 
Among the models most often used to describe the rheological behavior of fruit pulps is 
the Ostwald de Waele power law (TORALLES et al., 2006). Numerous authors have 
successfully described the flow behavior of various pulps using this model, for example, 
peach pulp (MUÑOZ et al., 2012) and mango pulp of different varieties (VIDAL et al.,2004; 
ORTEGA-QUINTANA et al., 2015; FIGUEROA-FLÓREZ et al., 2017). In this case, the 
experimental data for the viscosity and shear rate were fitted to the Carreau-Yasuda 
model (CARREAU, 1972), which gave us the best statistical parameters including a 
minimum correlation coefficient R2>0.99282: 
 



	

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 𝜂 = 𝜂! + 𝜂! −  𝜂! 1 + (𝜆!γ̇)!
!!!
!  (1) 

 
This model represents a fluid that follows Newton's law of viscosity at low deformation 
speeds and obeys a power law at high shear rates (MÉNDEZ-SÁNCHEZ et al., 2010). It 
uses five parameters: 𝜂! corresponds to the Newtonian viscosity at low shear rates; 𝜂! is 
the Newtonian viscosity at high deformation speeds; 𝜆! is the Carreau time constant; 𝑎 is 
the transition control factor, which is a dimensionless constant; and 𝑛 is the parameter of 
the power law model. In the case where n=1, the model is reduced to the linear Newtonian 
model, for example, the Navier-Stokes equations. For fluidifying liquids (n<1), the 
viscosity decreases with an increase in the shear rate. 

10-5 10- 4 10-3 10-2 10 -1 100 10 1 102 103 104
10-2

10-1

100

101

102

103

104

105

106

 Eggplant 10°C
 Eggplant 20°C
 Eggplant 25°C
 Eggplant 40°C
 Eggplant 60°C
 Eggplant 80°C
 Carreau Mod el

η
 (P

a.
s)

γ  (1/s)• 

 
Figure 1. Viscous flow curves for S. melongena pulp at different temperatures (10ºC, 20ºC, 25ºC, 40ºC, 60ºC, 
80ºC) fitted to the Carreau-Yasuda model. 
 
 
Fig. 1 shows the experimental data (viscosity vs. shear rate) fitted to the Carreau-Yasuda 
model. At the initial points, the apparent viscosity tends to be constant, and is represented 
as the null viscosity 𝜂𝑜. It subsequently begins to decrease, and the viscosity curve enters a 
logarithmic drop phase, where at high deformation speeds it tends to behave like a 
Newtonian fluid, following the behavior of the Carreau model. This decrease in viscosity 
with an increase in shear rate is called shear thinning, and similar results have been 
obtained in rheological studies of papaya pulp (QUINTANA et al., 2017). 
The fitting parameters of the Carreau-Yasuda model are shown in Table 2. The results 
demonstrate rheofluidifying (shear-thinning) behavior, with values for the flow behavior 
index of less than unity (n<1) for the different conditions of temperature. The viscosity 
decreases with the shear rate, and hence it is not considered an increase or decrease in the 



	

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fluidifying character of the pulps. However, changes in temperature affect the viscosity, 
since an increase in temperature produces greater intermolecular interaction in the 
aqueous phase of the pulp, causing repulsion between the suspended particles, lower 
resistance to flow, and consequently a decrease in the apparent viscosity (FIGUEROA-
FLÓREZ et al., 2017). This effect was also found by QUINTANA (2016), who showed that 
the results depended strongly on the heat treatment applied to the pulp before rheological 
analyses were carried out. 
 
 
Table 2. Rheological parameters of the Carreau-Yasuda model for the viscosity of eggplant pulp with 
variation in shear rate, at temperatures of 10-80°C. 
 

Temp. 𝜼𝟎 𝜼! 𝝀𝒄 𝒂 𝒏 R
2 

10°C   70390.99±1495.38 4.31E-47±0.01 2129.66±136.20   1.50±0 0.10±0.02 0.99 
20°C 48987.00±751.80   0.02±0.01 882.40±23.87 2.15±0.14 0.06±0.01 0.99 
25°C 96193.78±583.63 5.14E-37±0     980.64±0 5.00±0.33 0.02±0.01 0.99 
40°C 23964.83±654.76         0.08±0 643.23±10.68 17.61±5.43 0.08±0.01 0.99 
60°C   83051.70±5478.35 0.13±0.3   1222.66±48.54 1.25±0.13 0.05±0.02 0.99 
80°C 164922.94±5552.34   0.05±0.01 39.73±8.43 2.09±0.21 0.16±0.01 0.99 

 
 
The effect of temperature on the apparent viscosity of fluid foods (at constant shear rate) 
can be explained by the Arrhenius equation (DAK et al., 2007; RAO and TATTIYAKUL, 
1999), expressed as: 
 
 𝜂 = 𝐴𝑒𝑥𝑝 !!

!"
 (2) 

 
where A is the pre-exponential factor; 𝐸𝑎 is the activation energy, a parameter used to 
evaluate the thermal dependence (J/mol); R is the gas constant (8.314 J/mol K); and T is 
the temperature absolute (K). In this model, the apparent viscosity decreases in an 
exponential way with temperature. A shear rate of 15 s-1 was selected, since operations 
such as flow in pipes, mixing and agitation involve a range of shear speed of 10–1000 s-1 
(STEFFE, 1996). 
The experimental data for η can be well modeled by the Arrhenius equation, as shown in 
Fig. 2, and the values for R2 are found to be greater than 0.9387. The effect of temperature 
on apparent viscosity (at a constant shear rate) can also be observed in Fig. 2. 
In this case, the activation energy E𝑎=1081.61894 J/mol was lower than the values reported 
for squash pulp (𝐸𝑎 = 1229.46 J/mol) (QUINTANA et al., 2018); acerola pulp (𝐸𝑎=12637.89-
14292.45 J/mol) (PEREIRA et al., 2014); sapodilla pulp (𝐸𝑎=12637.89 J/mol) (ANDRADE-
PIZARRO et al., 2010) and tomato paste (𝐸𝑎=8600-13000 J/mol) (DAK et al., 2008), 
indicating that eggplant pulp has a higher sensitivity to changes in temperature in a food 
transpiring process; in other words, the internal structure of eggplant pulp is more 
affected by temperature than the other pulps or food products mentioned above. 
The activation energy is a very important parameter in terms of the movement of the 
molecules, as it influences when the temperature increases in the liquids, allowing them 
flow more easily, due to a high activation energy at high temperatures (MEMNUNE et al., 
2005). In this case, an increase in temperature causes a decrease in the viscosity of the 



	

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liquid phase, thus increasing the movement of the suspended particles and causing a 
decrease in the viscosity of the pulp (PELEGRINE et al., 2002). 
 

0,0028 0,0029 0,0030 0,0031 0,0032 0,0033 0,0034 0,0035
4

6

8

10

 Viscosity
 Arrhenius model

η
 (

P
a.

s)

Temperature (1/K) Τ  
 
Figure 2. Variation in the values of η obtained at 15 s-1 as a function of temperature and fit to the Arrhenius 
model. 
 
 
4. CONCLUSIONS 
 
Based on the results obtained in this investigation, the eggplant pulp have a the mayor 
content expressed in percentage for moisture and carbohydrates, 90.98 and 6.86±0.17 
respectively. The rheological properties of the pulp behave like a non-Newtonian fluid of 
rheofluidifying type (shear thinning). All samples showed a decrease in viscosity with 
shear rate, which was fitted to the Carreau-Yasuda model with R2>0.99. The influence of 
temperature on the behavior of the pulp was observed, and the eggplant pulp was found 
to lose pseudoplasticity and become less consistent as the temperature increases and its 
rheological parameters are affected. The relationship between the temperature and the 
apparent viscosity of the pulp can be represented by the Arrhenius equation, where an 
increase in temperature causes a decrease in viscosity. Finally, by examining the 
rheological and flow properties of eggplant pulp, this study may encourage new 
applications and may help in the design of new food products from this raw material of 
national interest. 
 
 
REFERENCES 
 
Alves Dos Santos K., Machado L., Sossela De Freitas R. and Cachoeira Stertz S. 2002. Composição química da berinjela 
(Solanum melongena L.). B. Ceppa, Curitiba. 20:247. 
 
Andrade R., Torres R., Montes E. and Pérez O. 2009. Efecto de la temperatura en el comportamiento reológico de la 
pulpa de níspero (Achras sapota L.). Rev. Fac. Agron. 26(4). 
 



	

Ital. J. Food Sci., vol. 32, 2020 - 603 

 

Andrade-Pizarro R., Torres-Gallo R., Montes-Montes E., Pérez-Sierra O., Bustamante-Vargas C. and Mora-Vargas B. 
2010. Effect of temperature on the rheological behavior of zapote pulp (Calocarpum sapota Merr). Rev. Téc. Ing. Univ. 
Zulia 33(2). 
 
Aramendiz-Tatis H., Espitia M. and Cardona C. 2010. Análisis de sendero en Berenjena (Solanum melongena L.). Revista 
U.D.C.A Actualidad & Divulgación Científica 13(1):115. 
 
Augusto P., Ibarz A. and Cristianini M. 2012. Effect of high pressure homogenization (HPH) on the rheological 
properties of a fruit juice serum model. J. Food Eng. 111:474. DOI: doi.org/10.1016/j.jfoodeng.2012.02.033  
 
Bhandari P., Singlhal R. and Kale D. 2002. Effect of succinylation on the rheological profile of starch pastes. Carbohydr. 
Polym. 47:365. DOI: doi.org/10.1016/S0144-8617(01)00215-6  
 
Cañas-Ángel Z., Restrepo-Molina. D. and Cortés-Rodríguez M. 2011. Revisión: Productos vegetales como fuente de fibra 
dietaria en la industria de alimentos. Rev. Fac. Nal. Agr. Medellín. 64(1):6023. 
 
Carreau P. 1972. Rheological equations from molecular network theories. Trans. Soc. Rheol. 16:99. DOI: doi.org/10.1122/ 
1.549276  
 
Dak M., Verma R. and Jaaffrey S. 2007. Effect of temperature and concentration on rheological properties of “Kesar” 
mango juice. J. Food Eng. 80:1011. DOI: doi.org/10.1016/j.jfoodeng.2006.08.011  
 
Dak M., Verma R. and Jaaffrey S. 2008. Rheological properties of tomato concentrate. Int. J. Food Eng. 4(7): article 11. 
DOI: doi.org/10.2202/1556-3758.1470  
 
De Castilhos M., Betiol L., De Carvalho G. and Telis-Romero J. 2017. Experimental study of physical and rheological 
properties of grape juice using different temperatures and concentrations. Part I: Cabernet Sauvignon. Food Res. Int. 724. 
DOI: doi.org/10.1016/j.foodres.2017.07.075  
 
Díaz-Ocampo R., García-Zapateiro L., Franco-Gomez J. and Vallejo-Torres C. 2012. Caracterización bromatológica, 
fisicoquímica microbiológica y reológica de la pulpa de borojó (borojoa patinoi cuatrec). Ciencia y Tecnología 5(1):17. 
 
FAO. 2015. Organización de las naciones unidas para la agricultura y la alimentación.[En línea]. Available: 
www.fao.org/faostat/es/?#data/QC/visualize  
 
Figueroa-Flórez J., Barragán-Viloria K. and Salcedo-Mendoza J. 2017. Comportamiento reológico en pulpa edulcorada de 
mango (Mangifera indica L. cv. Magdalena river). Corpoica, Cienc Tecnol Agropecuaria 18(3):615. DOI: doi.org/10.21930/ 
rcta.vol18_num3_art:748 
 
Franco J. M., Gallegos C. and Barnes H. A. 1998. On slip effects in steady-state flow measurements of oil-in-water food 
emulsions, J. Food Eng. 36(1):89-102. DOI: doi.org/10.1016/s0260-8774(98)00055-7 
 
García E., Hernández E., Aramendiz H. and De Paula C. 2003. Caracterizacion bromatologica de la berenjena (Solanum 
melongena L.) en el departamento de Cordoba. Temas Agrarios 8(1):27. 
 
Guerrero S. and Alzamora S. 1998. Effect of pH, temperature and glucose addition on flow behaviour of fruit purees: II. 
Peach, papaya and mango purées. J. Food Eng. 37:77. DOI: doi.org/10.1016/S0260-8774(98)00065-X  
 
Holdsworth, S. 1971. Applicability of rheological models to the interpretation of flow and processing behaviour of fluid 
food products. J. Texture Stud. 2:393. DOI: doi.org/10.1111/j.1745-4603.1971.tb00589.x  
 
Ibarz A., Garvín A. and Costa J. 1996. Rheological behavior of sloe (Prunus spinosa) juices. J. Food Eng. 27: 423. 
DOI: doi.org/10.1016/0260-8774(95)00024-0  
 
Ibarz A., Gonzalez C. and Esplugas S. 1996. Rheology of clarified passion fruit juices. Fruit Process. 6(8):330. 
DOI: doi.org/10.1111/j.1745 4603.1971.tb00589.x  
 
Instituto Colombiano de Bienestar Familiar (ICBF). 2015. Tabla de composicion de alimentos colombianos. Bogotá. 
www.icbf.gov.co/sites/default/files/tcac_2015_final_para_imprimir.pdf  
 
Memnune S., Fatih M. and Mustafa E. 2005. Rheological, physical and chemical characteristics of mulberry pekmez. Food 
Control 16:73. DOI: doi.org/10.1016/j.foodcont.2003.11.010  
 
Méndez-Sánchez A., Pérez-Trejo L. and Paniagua Mercado A. 2010. Determinación de la viscosidad de fluidos 
newtonianos y no Newtonianos (una revisión del viscosímetro de Couette). Latin-American Journal of Physics Education 
4(1):23.  



	

Ital. J. Food Sci., vol. 32, 2020 - 604 

 

 
Moreiras O., Carbajal A., Cabrera L. and Cuadrado C. 2013. Tablas de composición de alimentos. España: Ediciones 
Pirámide. 16th ed. 
 
Muller H. 1973. An introduction to food rheology. London. Cap. 6:57. Heinemann. 
 
Muñoz E., Rubio L. and Cabeza M. 2012. Comportamiento de flujo y caracterización fisicoquímica de pulpas de 
Durazno. Scientia Agropecuaria 2:107. DOI: doi.org/10.17268/sci.agropecu.2012.02.01  
 
Niño-Medina G., Urías-Orona V., Muy-Rangel M. and Heredia J. 2017. Structure and content of phenolics in eggplant 
(Solanum melongena). S. Afr. J. Bot. 111: 161. DOI: doi.org/10.1016/j.sajb.2017.03.016  
 
Nisha P., Abdul N. and Jayamurthy P. 2009. Comparative study on antioxidant activities of different varieties of Solanum 
melongena. Food Chem. Toxicol. 47:2640. DOI: doi.org/10.1016/j.fct.2009.07.026  
 
Ortega-Quintana E., Salcedo-Galván E., Arrieta-Rivero R. and Torres-Gallo R. 2015. Efecto de la temperatura y 
concentración sobre las propiedades reológicas de la pulpa de mango variedad Tommy Atkins. Revista Ion. 28(2):79. 
DOI: doi.org/10.18273/revion.v28n2-2015007  
 
Pelegrine D., Silva F. and Gasperrato C. 2002. Rheological behavior of mango and pineapple pulps. LWT Food Sci. 
Technol. 35(1):645. DOI: doi.org/10.1006/fstl.2002.0920  
 
Pereira C., De Resende J. and Giarola T. 2014. Relationship between the thermal conductivity and rheological behavior of 
acerola pulp: Effect of concentration and temperature. LWT Food Sci. Technol. 58:446. DOI: doi.org/10.1016/j.lwt.2014. 
04.016  
 
Quintana S., Marsiglia R., Torregroza E., Franco J. and García-Zapateiro, L. 2016. Efecto del tratamiento térmico sobre las 
propiedades reológicas de la pulpa de ahuyama (Cucurbita moschata). Agron. Colomb. 34(1):659.  
 
Quintana S., Granados C. and García-Zapateiro L. 2017. Propiedades reológicas de la pulpa de papaya (Carica papaya). 
Información Tecnológica 28(4):11. DOI: doi.org/10.4067/S071807642017000400003  
 
Quintana S., Machacon D., Marsiglia R., Torregroza E. and García-Zapateiro L. 2018. Steady and shear dynamic 
rheological properties of squash (Cucurbita moschata) pulp. Contemporary Engineering Sciences 11(21):1013. 
DOI: doi.org/10.12988/ces.2018.8386  
 
Rao M. and Tattiyakul J. 1999. Granule size and rheological behavior of heated tapioca starch dispersions. Carbohydr. 
Polym. 38:123. DOI: doi.org/10.1016/S0144-8617(98)00112-X  
 
Salunkhe D. and Desai B. 1984. Chapter 4. Eggplant: Postharvest Biotechnology of Vegetables. Volume II. Boca Raton, 
Florida, CRC Press. 39-47. 
 
San José R., Sánchez M., Cámara M. and Prohens J. 2013. Composition of eggplant cultivars of the occidental type and 
implications for their improvement of nutritional and functional quality. Int. J. Food Sci. Technol. 42:2490. DOI: doi.org/ 
10.1111/ijfs.12240  
 
Steffe J. 1996. Rheological methods in food process engineering. 2nd edition, Michigan. USA: Editorial Freeman Press, East 
Lansing. 
 
Sun J., Song Y., Zhang J., Huang Z., Huo H., Zheng J., Zhang Q., Zhao Y., Li J. and Tu, P. 2015. Characterization and 
quantitative analysis of phenylpropanoid amides in eggplant (Solanum melongena L.) by high performance liquid 
chromatography coupled with diode array detection and hybrid ion trap time-of-flight mass spectrometry. J. Agric. Food 
Chem. 63:3426. 
 
Toralles R., Vendruscolo J. and Vendruscolo C. 2006. Reológia de purê homogeneizado de Pêssego: Efeito da 
temperatura e concentração. Braz. J. Food Technol. 9(1):1.  
 
Vidal J., Pelegrine D. and Gasparetto C. 2004. Efeito da temperatura no comportamento reológico da polpa de manga 
(mangífera indica L. Keitt). Ciênc. Tecnol. Aliment. 24(1):039. DOI: doi.org/10.1590/S010120612004000100008 
 
 
 

Paper Received September 15, 2019  Accepted February 14, 2020