Emulsification properties, mixed

Peanut Seed. Ramanatham et al. (21) studied the influence of such variables as protein concentration, particle size, speed of mixing, pH, and presence of sodium chloride on emulsification properties of peanut flour (50% protein) and peanut protein isolate (90% protein). Emulsions were prepared by the blender... 

Sunflower Seed. Emulsion capacity of defatted sunflower meal was investigated by Huffman et al. (45) at three pH levels (5.2, 7.0, 10.8), blender speeds (4500, 6500, 9000 rpm), and oil addition rates (30, 45, 60 ml/min). With low mixing speeds and rapid rates of oil addition, optimum emulsion capacity occurred at pH 7.0. These authors related the observed emulsification properties to protein solubility, surface area and size of oil droplets, and rate of protein film formation. 

In addition to the surfactant and epoxy resin, the parameters of the emulsification process will significantly influence the properties of the final emulsion. To obtain the smallest achievable droplet size with a narrow droplet size distribution, it is essential to optimize process parameters such as temperature of emulsification and mix ratio of surfactants when more than one surfactant is used. 

The focus here is on these mechanisms. A high content of naphthenic acids in heavy oils is a good property for soap generation and emulsification. Therefore, this chapter also presents the synergy between alkali and surfactant in heavy oil reservoirs. First, it discusses the phase behavior of the mixed system of soap and surfactant. Then it describes how to build up a UTCHEM phase behavior model and how to use the model to analyze phase behavior. In addition, this chapter investigates a number of parameters related to phase behavior. 

An essential role of the surfactant is to prevent the newly formed drops from coalescing again. Drops frequently encounter each other during the emulsification process. Recoalescence has been shown to occur in the following type of experiment. Two O-W emulsions are made that have identical properties, except that two oils are used that differ, e.g., in refractive index. These emulsions are then mixed and the mixture is rehomogenized. By comparing the refractive index of the droplets so obtained with that of the original ones, it follows that droplets of mixed oil composition have indeed been formed. 

The dissociation of a quaternary structure or denaturation of proteins is required prior to emulsification. Therefore, casein micelles are adsorbed at an interface in a semi-intact form (Oortwijn et al., 1977). The thermal denaturation of globular proteins prior to emulsification was reported to improve the emulsifying properties. The high level of the thermally denatured whey protein fraction in mixed proteins (of denatured and undenatured proteins) increased the emulsion viscosity and coalescence stability compared with the low-level denatured fraction (Britten et al., 1994). 

Favis [1994] and Willis andFavis [1988] prepared compatibilized PA blends with PP and carboxylic acid-functionalized EMAA ionomer. Blends containing 90-10 parts PA-6, 0-30 parts EMAA ionomer, and 10-90 parts PP were combined in an internal mixer at 250°C and characterized by torque rheometry and SEM. Dispersed phase particle size vs. interfacial modifier concentration was determined. Emulsification curves were constructed. Effects of mixing protocol on blend properties were studied. Blends were also prepared containing HOPE in place of PP. 

The importance of the properties of the interfacial region for spontaneous emulsification was first demonstrated by Gad (4), who observed that when a solution of lauric acid in oil was carefully placed on an aqueous alkaline solution, an emulsion spontaneously formed at the interface. The reason for this spontaneous emulsification is the formation of a mixed film of lauric acid and sodium laurate (produced by partial neutralization of the acid by alkali) which produces an ultra-low interfacial tension. 

Microgels can be produced by the mixing and emulsification of two different polymer solutions that can react to form cross-linked microgel particles that are monodisperse and have predictable swelling properties [8]. An example of this is the use of aldehyde and hydrazide-functionaUzed carbohydrates where heating or UV irradiation can be used for gelation. 

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