Protein-stabilized emulsions emulsion

S. Mohan and G. Narsimham Coalescence of Protein-Stabilized Emulsions in a High-Pressure Homogenizer. J. Colloid Interface Sci. 192, 1 (1997). 

E. Tomherg Punctional Characterization of Protein Stabilized Emulsions Emulsifying Behavior of Proteins in a Valve Homogenizer. J. Sci. Pood Agric. 29, 867 (1978). 

As reported in this chapter, the microscopic origin of both compressibility and elasticity of dense emulsions is rather well understood. Emulsions have elastic properties arising from either surface tension or surface elasticity and plasticity. Some protein-stabilized emulsions obey the same phenomenology as solid-stabilized emulsions they exhibit substantially higher osmotic resistances and higher shear moduli than surfactant-stabilized emulsions [38 0]. Moreover, they are strongly resistant to water evaporation. Proteins possess the ability to form... 

E. Dickinson and I. Chen Viscoelastic Properties of Protein-Stabilized Emulsions Effect of Protein-Surfactant Interactions. I. Agric. Food Chem. 46, 91 (1998). 

T. D. Dimitrova and F. Leal Calderon Bulk Elasticity of Concentrated Protein-Stabilized Emulsions. Langmuir 17, 3235 (2001). 

Model for Centrifugal Stability of protein Stabilized Concentrated Emulsions... 

Damodaran, S. (2005). Protein stabilization of emulsions and foams. Journal of Food... 

McClements, D.J. (2004). Protein-stabilized emulsions. Current Opinion in Colloid and Interface Science, 9, 305-13. 

Figure 3.4 Effect of polysaccharide on protein-stabilized emulsions. The diameter ratio, j43nuxtlire / J43protem is plotted against the molar ratio R (moles polysaccharide / moles protein). Here J43nuxtlire is average droplet diameter in fresh emulsion prepared with protein + polysaccharide, and d43pTOtQm is average diameter in emulsion stabilized by protein alone. Key , , legumin + dextmn (48 kDa) or legumin + dextran (500 kDa), respectively (0.5 w/v % protein, 10 vol% oil, pH = 8.0, /= 0.1 M) (Dickinson and Semenova, 1992) O, , asi-casein + pectinate and p-casein + pectinate at pH = 7.0, / = 0.01 M (2.0 w/v % protein, 40 vol% oil), respectively , p-casein + pectinate at pH = 5.5, / = 0.01 M (2.0 w/v % protein, 40 vol% oil) (Semenova et al, 1999). Reproduced from Semenova (2007) with permission.

Dickinson, E., Pawlowsky, K. (1997) Effect of i-carrageenan on flocculation, creaming, and rheology of a protein-stabilized emulsion. Journal of Agricultural and Food Chemistry, 45, 3799-3806. 

For a colloidal system containing a mixture of different biopolymers, in particular a protein-stabilized emulsion containing a hydrocolloid thickening agent, it is evident that the presence of thermodynamically unfavourable interactions (A u > 0) between the biopolymers, which increases their chemical potentials (thermodynamic activity) in the bulk aqueous phase, has important consequences also for colloidal structure and stability (Antipova and Semenova, 1997 Antipova et al., 1997 Dickinson and Semenova, 1992 Dickinson et al., 1998 Pavlovskaya et al., 1993 Tsap-kina et al., 1992 Semenova et al., 1999a Makri et al., 2005 Vega et al., 2005 Semenova, 2007). 

Figure 7.9 Effect of pectin (DE = 76%) on (a) creaming of protein-stabilized emulsions (11 vol% oil, 0.6 wt% protein, 0.28 wt% pectin, I = 0.01 M) containing (A) asi-casein (pH = 7), (A) p-casein (pH = 7), and ( ) o i-casein (pH = 5.5) and (b) steady-state shear viscometry of casein-stabilized emulsions (40 vol% oil, 2 vt% protein). Apparent shear viscosity at 22 °C is plotted against stress pH = 7.0, / = 0.01 M, (A) -casein, (A) p-casein, ( ) ocsi -casein + 0.5 wt% pectin, ( ) p-casein + 0.5 wt% pectin, ( ) p-casein + 1.0 wt% pectin, (O) as[-casein + 1.0 wt% pectin pH = 5.5,1 = 0.01 M, (x) ocsi -casein, (O) as[-casein + 0.5 wt% pectin, ( ) oc -casein + 1.0 wt% pectin. Reproduced from Semenova (2007) with permission.

In the study of Neirynck et al. (2007), the electrophoretic mobility data indicated that whey protein-stabilized emulsion droplets became gradually more negatively charged with pectin addition at pH = 5.5. This change was not only reflected in a smaller average droplet size, but also in a significant improvement in the creaming stability of the emulsions. 

Gancz, K., Alexander, M., Corredig, M. (2006). In situ study of flocculation of whey protein-stabilized emulsions caused by addition of high-methoxy 1 pectin. Food Hydro-colloids, 20, 293-298. 

Dickinson, E., Owusu, R.K., Williams, A. (1993b). Orthokinetic destabilization of a protein-stabilized emulsion by a water soluble surfactant. Journal of the Chemical Society, Faraday Transactions, 89, 865-866. 

Some products, like butter and margarine are stabilized by fat crystals. Salad dressings and beverage emulsions are stabilized by other emulsifiers. The stability of non-protein stabilized food emulsions, involving lower molar mass type molecules, tend to be better described by the DLVO theory than are protein-stabilized emulsions. An example of an O/W emulsifier whose emulsions are fairly well described by DLVO theory is sodium stearoyl lactylate [812],... 

Dalgleish, D.G. 1989. Protein-stabilized emulsions and their properties. In Water and Food Quality (T.M. Hardman, ed.), pp. 211-250, Elsevier Applied Science, London. 

Klemaszewski, J.L., Haque, Z., Kinsella, J.E. 1989. An electronic imaging system for determining droplet size and dynamic breakdown of protein-stabilized emulsions. J. Food Sci. 54, 440-445. 

---