Protein emulsifier

A stable foam is likely to have ingredients that are in a low energy state at the air-liquid interface. Substances that fit this description include proteins, emulsifiers some fats and fat components such as diglycerides monoglycerides and fatty acids. Food law uses the term emulsifier and stabiliser to cover the situation where the ingredient is stabilising an emulsion rather than helping to form it. 

The presence of a thermodynamically incompatible polysaccharide in the aqueous phase can enhance the effective protein emulsifying capacity. The greater surface activity of the protein in the mixed biopolymer system facilitates the creation of smaller emulsion droplets, i.e., an increase in total surface area of the freshly prepared emulsion stabilized by the mixture of thermodynamically incompatible biopolymers (see Figure 3.4) (Dickinson and Semenova, 1992 Semenova el al., 1999a Tsapkina et al., 1992 Makri et al., 2005). It should be noted, however, that some hydrocolloids do cause a reduction in the protein emulsifying capacity by reducing the protein adsorption efficiency as a result of viscosity effects. 

Rodriguez Patino, J.M., Rodriguez Nino, M.R., Sanchez, C.C. (2003). Protein-emulsifier interactions at the air-water interface. Current Opinion in Colloid and Interface Science, 8, 387-395. 

In whippable emulsions with a high fat content, the air-water interface of the foam after whipping is dominated by adsorbed deproteinated fat globules. In whippable emulsions with a low fat content other foam stabilizing mechanisms come into play, such as protein-hydrocolloid and protein-emulsifier interactions. The former subject may be studied by... 

Barfod N.M., Krog, N. and Buchheim, W., Lipid-protein emulsifier-water interactions in whippable emulsions, in "Food Proteins", J.E. Kinsella and W.G. Soucie (Eds.), Am. Oil Chem. Soc., Champaign, Illinois (1989) 144. 

Tornberg and Ediriweera, 1987). Phase inversion temperature (Shinoda and Saito, 1969) and emulsifying capacity (Swift et al., 1961) have been used to evaluate the effects of low molecular weight and protein emulsifiers, respectively. Unfortunately, it is not possible to measure the size of the large droplets present in unhomogenized water-in-oil emulsions because the droplets coalesce very quickly. The phase inversion temperature is not a relevant test, as it may not be related directly to the stability to inversion at the emulsification temperature. Furthermore, it has been stated (Matsumoto and Sherman, 1970) that water-in-oil emulsions do not exhibit a true phase inversion temperature, unlike oil-in-water emulsions. 

A wide range of doses and immunization schedules has been used successfully. A convenient schedule for immunization of rabbits is to inject 200-500 fjLg of conjugated protein, emulsified in complete Freund s adjuvant, intradermally and subcutaneously on the first day, and to inject the same dose in incomplete adjuvant on days 14 and 21. Serum can be obtained 5-7 days later. Further bleedings may be done weekly, with intra-dermal booster injections given if the serum antibody levels fall. After an... 

As for pure LMWE films, the surface dilatational modulus is higher for protein-saturated-LMWE than for protein-unsaturated-LMWE mixed films at every surface pressure. The surface dilatational properties of mixed protein-emulsifier films also depend on the presence of some food components (ethanol and sucrose) in the aqueous phase. In general, a decrease in the dilatational rheological properties on the addition of ethanol was found for protein-water-insoluble LMWE. That is, the static and... 

Britten, M., Giroux, H.J., Jean, Y, and Rodrigue, N. 1994. Composite blends from heat-denatured and undenatured whey protein Emulsifying properties. International Dairy Journal 4 25-36. 

The emulsifying activity of proteins [143] increased in the pH range of 2-9 [144] upon hydrolysis of soy proteins. Emulsifying capacity was also increased by hydrolysis of soy. Proteolysis of soy protein had no effect on foam stability [144,118], but hydrolysis of zein increased foam stability [145]. 

Protein Emulsifying property Whipping property Gelation property Film formation Environmental stability... 

Hu, M., McClements, J., and Decker, E.A., Impact of whey protein emulsifiers on the oxidative stabihty of salmon oil-in-water emnlsions, J. Agric. Food Chem., 51,1435, 2003. 

Williams and Janssen (20) studied the behavior of droplets in a simple shear flow in the presence of a protein emulsifier. The effect of two structurally diverse protein emulsifiers, P-lactoglobulin and P-casein, upon the breakup behavior of a single aqueous droplet in a Couette flow field has been studied over a wide range of protein concentrations. It was found that P-casein and low concentrations of P-lactoglobulin cause the droplets to be at least as stable as expected from conventional theories based on the equilibrium interfacial tension. In such cases the presence of the emulsifier at the deforming interface is thought to enhance the interfacial elasticity. This effect can be characterized by... 

Uses 0/w and w/o emulsifier, wetting agent, crystallization inhibitor, softener, conditioner, aerating agent in foods emulsifier in cosmetics inhibitor of thermal denaturation of proteins emulsifier, solubilizer, stabilizer, tableting agent, lipophilic matrix in... 

Sodium/TEA-lauroyl hydrolyzed keratin TEA-cocoyl hydrolyzed soy protein emulsifier, auxiliary chloroprene rubbers Dimer acid... 

AMP isostearoyl hydrolyzed wheat protein emulsifier, natural fats Sorbitan trioleate emulsifier, natural waxes Sorbitan trioleate... 

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