Document Type : Full Research Paper


1 Center of Excellence in Native Natural Hydrocolloids of Iran, Department of Food Science and Technology, Ferdowsi University of Mashhad, Iran.

2 Department of Food Science and Technology, Faculty of Agriculture, Ferdowsi university of Mashhad,


Introduction: Proteins and polysaccharides are natural biopolymers that consider among the most widely used hydrocolloids in the food industry (Gaonkar and McPherson 2006) Which are often used simultaneously to improve functional properties. In electrostatic interaction, positively charged proteins with polysaccharides containing negative groups below the protein isoelectric point (PI) (LEE, MORR, and HA 1992), Leads to the formation of macromolecular particles by creating molecular aggregates rich in biopolymers suspended in the aqueous phase, called complex coacervate, which cause the coagulation and spontaneous separation of the phase. The ratio of protein-polysaccharide biopolymers and the pH of the mixture are important factors influencing the adsorption and compatibility of protein- polysaccharides as well as the characteristics of their aggregates (Shu et al. 1996). For this purpose, the optical density (turbidity) of protein-polysaccharide mixtures and the yield of dried sediments in this study as a basis for optimizing the complex coacervate process as in previous studies (Wang, Adhikari, and Barrow 2014; Huang et al. 2012) were used. In the present study, the optimization of complex coacervate formation conditions of whey protein concentrate-cress seed gum as well as the foaming properties of complex coacervate were studied for the first time. Whey proteins, as amphiphilic macromolecules, can adsorb at the interface (Scheer, Kruppke, and Heib 2001; Tamm et al. 2012; Wierenga and Gruppen, 2010) and form a viscoelastic adsorbent layer (Wilde 2000). Also, whey protein acts as a foaming agent with the ability to be adsorbed at the joint water-oil and water-air interface through hydrophobic interactions or disulfide bridges, and intermolecular bonds (Nicorescu et al. 2008; Nicorescu et al., 2008; Dickinson, 1992; Forschen, 2017). Cress seed gum has rheological, emulsifying, favorable foaming properties and is stable in a wide range of heat, cold, salt, and pH with synergistic effects in the presence of sugars (sucrose, lactose). These properties are important in stabilizing emulsions and foams. The general purpose of this study was to achieve the optimal point of electrostatic interaction of different ratios of whey protein concentrate with cress seed gum in the pH range of 2 to 7 using response surface methodology and to investigate the foaming properties of the coacervate complex at the optimal point in comparison with Pure control protein in the same ratio.
Materials and Methods: The raw materials of this study included cress seed, whey protein concentrate with 80% purity (from Milli com., Germany), and hydrochloric acid with 37% purity (from Merck Com.). Different protein-polysaccharide mixtures were prepared to optimize the electrostatic interaction with the ratio of biopolymers (1: 5 to 5: 1 w / w) and pH of interaction (2 to 7). Mixtures, in the ratio determined by the software and the total concentration of biopolymer (0.3%), were prepared, and after 15 minutes of stirring and equilibration with the environment, were adjusted by hydrochloric acid of 0.1, 0.5, and 1 (n) to the desired pH, and stirred for 5 minutes at each pH with a magnetic stirrer at 400 rpm. Optical Density (OD) of protein: polysaccharide mixtures was evaluated by visible-ultraviolet optical spectrophotometry (Unico, Model S-2150, USA). To optimize the electrostatic complex coacervation process, the coacervation yield was determined. The result of the interaction of whey protein concentrate and cress seed gum as a function of pH and protein to gum ratio was investigated by measuring the sediment phase. For investigation of the foaming properties, the dispersions were homogenized using a homogenizer (Ultra Turrax T25 Digital) for 5 minutes at a speed of 10,000 rpm. After recording the sample volume in the dimension and before homogeneity, the foaming capacity was calculated. To determine the stability of the foam, changes in the volume of the samples were recorded and calculated after 30 minutes of foaming. In this study, the effect of two independent variables including the ratio of biopolymers in the range of 0.2-5 (w/w) and the pH within the range of 2 to 7 were analyzed using Design-Expert software based on two responses including turbidity and yield by the combined central design (CCD) with 5 replications to optimize the electrostatic interaction of whey protein concentrate with cress seed gum.
Results and Discussion: The results obtained by using response surface methodology showed that the independent variables (ratio of whey protein to cress seed gum and pH) in this study affected the studied responses (turbidity and sediment percentage), although pH had the greatest effect. Optimal conditions for the formation of the maximum protein-polysaccharide coacervate complex were obtained in the ratio of protein to polysaccharide 5: 1 (w / w) and pH 4.24. The results of foaming properties at the optimal point showed an increase in foaming capacity and foam stability compared to pure protein (control sample). This increase in foaming properties is probably due to the presence of cress seed gum and its effect on the formation of a thick viscoelastic film, improved protein adsorption at the interface, and increased bulk phase viscosity.


Main Subjects

  1. Adebowale, Y. A., I. A. Adeyemi, and A. A. Oshodi. 2005. “Functional and Physicochemical Properties of Flours of Six Mucuna Species.” African Journal of Biotechnology 4 (12): 1461–68.

    Behrouzian, Fataneh, Seyed M.A. Razavi, and Hojjat Karazhiyan. 2013. “The Effect of PH, Salts and Sugars on the Rheological Properties of Cress Seed (Lepidium Sativum) Gum.” International Journal of Food Science and Technology 48 (12): 2506–13.

    Carp, D. J., G. B. Bartholomai, and A. M.R. Pilosof. 1999. “Electrophoretic Studies for Determining Soy Proteins-Xanthan Gum Interactions in Foams.” Colloids and Surfaces B: Biointerfaces 12 (3–6): 309–16.

    Cavallieri, Angelo L.F., Natalia Amanda Vieira Fialho, and Rosiane L. Cunha. 2011. “Sodium Caseinate and κ-Carrageenan Interactions in Acid Gels: Effect of Polysaccharide Dissolution Temperature and Sucrose Addition.” International Journal of Food Properties 14 (2): 251–63.

    Dickinson, Eric. 1992. “Structure and Composition of Adsorbed Protein Layers and the Relationship to Emulsion Stability” 88 (20): 2973–83.

    1. Makri, E. Papalamprou, G. Doxastakis* Laboratory. 2005. “Study of Functional Properties of Seed Storage Proteins from Indigenous European Legume Crops (Lupin, Pea, Broad Bean) in Admixture with Polysaccharides.” Food Hydrocolloids 19 (3): 583–94.

    Espinosa-Andrews, Hugo, Juan G. Báez-González, Francisco Cruz-Sosa, and E. Jaime Vernon-Carter. 2007. “Gum Arabic-Chitosan Complex Coacervation.” Biomacromolecules 8 (4): 1313–18.

    Forschen, Sci. 2017. “Sci Forschen Nutrition and Food Technology : Open Access Relation with Interfacial Properties.”

    Gaonkar, Anilkumar G., and Andrew McPherson. 2006. “Ingredient Interactions Efffects on Food Quality,” 573.

    Harnsilawat, Thepkunya, Rungnaphar Pongsawatmanit, and D. J. McClements. 2006. “Characterization of β-Lactoglobulin-Sodium Alginate Interactions in Aqueous Solutions: A Calorimetry, Light Scattering, Electrophoretic Mobility and Solubility Study.” Food Hydrocolloids 20 (5): 577–85.

    Hasanvand, Elham, Ali Rafe, and Bahareh Emadzadeh. 2018. Phase Separation Behavior of Flaxseed Gum and Rice Bran Protein Complex Coacervates. Food Hydrocolloids. Vol. 82. Elsevier Ltd.

    Huang, Guo Qing, Yan Ting Sun, Jun Xia Xiao, and Jian Yang. 2012. “Complex Coacervation of Soybean Protein Isolate and Chitosan.” Food Chemistry 135 (2): 534–39.

    J.M.R.Patino, Ana M.R. Pilosof. 2011. “Protein-Polysaccharide Interactions at Fluid Interfaces.” Food Hydrocolloids 25 (8): 1925–37.

    Jones, Owen G., Uri Lesmes, Paul Dubin, and David Julian McClements. 2010. “Effect of Polysaccharide Charge on Formation and Properties of Biopolymer Nanoparticles Created by Heat Treatment of β-Lactoglobulin-Pectin Complexes.” Food Hydrocolloids 24 (4): 374–83.

    1. Borcherding1, P.Chr. Lorenzen?, W. Hoffmann, K. Schrader, and Max. 2008. “Effect of Foaming Temperature and Varying Time/Temperature-Conditions of Pre-Heating on the Foaming Properties of Skimmed Milk.” International Dairy Journal 18 (4): 349–58.

    Karazhiyan, Hojjat, Seyed M.A. Razavi, Glyn O. Phillips, Yapeng Fang, Saphwan Al-Assaf, and Katsuyoshi Nishinari. 2011. “Physicochemical Aspects of Hydrocolloid Extract from the Seeds of Lepidium Sativum.” International Journal of Food Science and Technology 46 (5): 1066–72.

    Karazhiyan, Hojjat, Seyed M.A. Razavi, Glyn O. Phillips, Yapeng Fang, Saphwan Al-Assaf, Katsuyoshi Nishinari, and Reza Farhoosh. 2009. “Rheological Properties of Lepidium Sativum Seed Extract as a Function of Concentration, Temperature and Time.” Food Hydrocolloids 23 (8): 2062–68.

    LEE, SHIH‐YOUNG ‐Y, CHARLES V. MORR, and EWAN Y.W. HA. 1992. “Structural and Functional Properties of Caseinate and Whey Protein Isolate as Affected by Temperature and PH.” Journal of Food Science 57 (5): 1210–29.

    Liu, S., C. Elmer, N. H. Low, and M. T. Nickerson. 2010. “Effect of PH on the Functional Behaviour of Pea Protein Isolate-Gum Arabic Complexes.” Food Research International 43 (2): 489–95.

    Lv, Yi, Xiaoming Zhang, Shabbar Abbas, and Eric Karangwa. 2012. “Simplified Optimization for Microcapsule Preparation by Complex Coacervation Based on the Correlation between Coacervates and the Corresponding Microcapsule.” Journal of Food Engineering 111 (2): 225–33.

    Makri, Eleousa A., and Georgios I. Doxastakis. 2007. “Surface Tension of Phaseolus Vulgaris and Coccineus Proteins and Effect of Polysaccharides on Their Foaming Properties.” Food Chemistry 101 (1): 37–48.

    Martinez, Karina D., Cecilio Carrera Sanchez, Victor Pizones Ruiz-Henestrosa, Juan M. Rodríguez Patino, and Ana M.R. Pilosof. 2007. “Soy Protein-Polysaccharides Interactions at the Air-Water Interface.” Food Hydrocolloids 21 (5–6): 804–12.

    Naji, Sara, Seyed M.A. Razavi, and Hojjat Karazhiyan. 2012. “Effect of Thermal Treatments on Functional Properties of Cress Seed (Lepidium Sativum) and Xanthan Gums: A Comparative Study.” Food Hydrocolloids 28 (1): 75–81.

    Naji, Sara, Seyed M.A. Razavi, Hojjat Karazhiyan, and Arash Koocheki. 2012. “Influence of Thermal Treatments on Textural Characteristics of Cress Seed (Lepidium Sativum) Gum Gel.” Electronic Journal of Environmental, Agricultural and Food Chemistry 11 (3): 222–37.

    Naji, Sara, and Seyed M.A. Razavin. 2014. “Functional and Textural Characteristics of Cress Seed (Lepidium Sativum) Gum and Xanthan Gum: Effect of Refrigeration Condition.” Food Bioscience 5: 1–8.

    Nerkar, Pankaj Padmakar, and Surendra Ganeshlal Gattan. 2012. “Cress Seed Mucilage Based Buccal Mucoadhesive Gel of Venlafaxine: In Vivo, in Vitro Evaluation.” Journal of Materials Science: Materials in Medicine 23 (3): 771–79.

    Nicorescu, I., C. Loisel, C. Vial, A. Riaublanc, G. Djelveh, G. Cuvelier, and J. Legrand. 2008. “Combined Effect of Dynamic Heat Treatment and Ionic Strength on Denaturation and Aggregation of Whey Proteins - Part I.” Food Research International 41 (7): 707–13.

    Oduse, Kayode, Lydia Campbell, Julien Lonchamp, and Stephen R. Euston. 2018. “Electrostatic Complexes of Whey Protein and Pectin as Foaming and Emulsifying Agents.” International Journal of Food Properties 20 (3): S3027–41.

    Raoufi, Nassim, Rassoul Kadkhodaee, Glyn O. Phillips, Yapeng Fang, and Masoud Najaf Najafi. 2016. “Characterisation of Whey Protein Isolate-Gum Tragacanth Electrostatic Interactions in Aqueous Solutions.” International Journal of Food Science and Technology 51 (5): 1220–27.

    Salminen, Hanna, and Jochen Weiss. 2014. “Effect of Pectin Type on Association and PH Stability of Whey Protein-Pectin Complexes.” Food Biophysics 9 (1): 29–38.

    Sanchez, C., M. Pouliot, S. F. Gauthier, and P. Paquin. 1997. “Thermal Aggregation of Whey Protein Isolate Containing Microparticulated or Hydrolyzed Whey Proteins.” Journal of Agricultural and Food Chemistry 45 (7): 2384–92.

    Scheer, August-wilhelm, Helmut Kruppke, and Ralf Heib. 2001. Springer-Verlag Berlin Heidelberg GmbH.

    Schmitt, Christophe, Christian Sanchez, Sylvie Desobry-Banon, and Joël Hardy. 1998. “Critical Reviews in Food Science and Nutrition Structure and Technofunctional Properties of Protein- Polysaccharide Complexes : A Review Structure and Technofunctional Properties of Protein-Polysaccharide Complexes : A Review.” Critical Reviews in Food Science and Nutrition 38 (8): 689–753.

    Schmitt, Christophe, and Sylvie L. Turgeon. 2011. “Protein/Polysaccharide Complexes and Coacervates in Food Systems.” Advances in Colloid and Interface Science 167 (1–2): 63–70.

    Shu, Yu Wei, Sigehiro Sahara, Soichiro Nakamura, and Akio Kato. 1996. “Effects of the Length of Polysaccharide Chains on the Functional Properties of the Maillard-Type Lysozyme-Polysaccharide Conjugate.” Journal of Agricultural and Food Chemistry 44 (9): 2544–48.

    Stone, Andrea K., Lamlam Cheung, Chang Chang, and Michael T. Nickerson. 2013. “Formation and Functionality of Soluble and Insoluble Electrostatic Complexes within Mixtures of Canola Protein Isolate and (κ-, ι- and λ-Type) Carrageenan.” Food Research International 54 (1): 195–202.

    Stone, Andrea K., and Michael T. Nickerson. 2012. “Formation and Functionality of Whey Protein Isolate-(Kappa-, Iota-, and Lambda-Type) Carrageenan Electrostatic Complexes.” Food Hydrocolloids 27 (2): 271–77.

    Stone, Andrea K., Anzhelika Teymurova, Chang Chang, Lamlam Cheung, and Michael T. Nickerson. 2015. “Formation and Functionality of Canola Protein Isolate with Both High- and Low-Methoxyl Pectin under Associative Conditions.” Food Science and Biotechnology 24 (4): 1209–18.

    Stone, Andrea K., Anzhelika Teymurova, and Michael T. Nickerson. 2014. “Formation and Functional Attributes of Canola Protein Isolate-Gum Arabic Electrostatic Complexes.” Food Biophysics 9 (3): 203–12.

    Tamm, F., G. Sauer, M. Scampicchio, and S. Drusch. 2012. “Pendant Drop Tensiometry for the Evaluation of the Foaming Properties of Milk-Derived Proteins.” Food Hydrocolloids 27 (2): 371–77.

    Timilsena, Yakindra Prasad, Bo Wang, Raju Adhikari, and Benu Adhikari. 2015. “Preparation and Characterization of Chia Seed Protein Isolate-Chia Seed Gum Complex Coacervates.” Food Hydrocolloids 52: 554–63.

    Vinayahan, T., P. A. Williams, and G. O. Phillips. 2010. “Electrostatic Interaction and Complex Formation between Gum Arabic and Bovine Serum Albumin.” Biomacromolecules 11 (12): 3367–74.

    Wang, Bo, Benu Adhikari, and Colin J. Barrow. 2014. “Optimisation of the Microencapsulation of Tuna Oil in Gelatin-Sodium Hexametaphosphate Using Complex Coacervation.” Food Chemistry 158: 358–65.

    Wang, Zhengshan, Sha Zhang, and Bongkosh Vardhanabhuti. 2015. “Foaming Properties of Whey Protein Isolate and λ-Carrageenan Mixed Systems.” Journal of Food Science 80 (8): N1893–1902.

    Weinbreck, Fanny, Hans Nieuwenhuijse, Gerard W. Robijn, and Cornelis G. De Kruif. 2003. “Complex Formation of Whey Proteins: Exocellular Polysaccharide EPS B40.” Langmuir 19 (22): 9404–10.

    Wierenga, P. A., and H. Gruppen. 2010. “New Views on Foams from Protein Solutions.” Current Opinion in Colloid and Interface Science 15 (5): 365–73.

    Wilde, P. J. 2000. “Interfaces: Their Role in Foam and Emulsion Behaviour.” Current Opinion in Colloid and Interface Science 5 (3–4): 176–81.