Aggregative emulsion stability

Considering that flocculation parameters were measured within 30 minutes, conditions were created where there was practically no change in the number or size of the particles. The aggregative emulsion stability changed in this case only due to the flocculation of single droplets whose size was practically constant. 

Nile Blue is used as a 0.01 to 0.1 %W/V aqueous solution and is simply added to or mixed with the substrate. The active component of the dye is actually a minor contaminant of the solution, not the blue-colored material [31]. The preparations are viewed with 450-490 nm excitation (an FTTC filter set. Figure 6). Emulsion stability is sometimes an issue in the presence of the cationic blue component of Nile Blue. In this case we use Nile Red, the pure form of this colorant. Nile Red solution is made fresh from a stock solution (0.1%W/V in acetone). This stock is added dropwise to water until a moderate blue color is seen and the solution is used immediately (it deteriorates quickly). For either colorant, the active molecule is fluorescent only when it is in a suitably hydrophobic environment. This usually means neutral lipid droplets [31] but other sites (aggregates of surfactants, the center of casein micelles, cutin plates in some seeds) are possibilities. 

Succinyl- ation Increased solubility at acidic pH, increased tolerance to Ca +, good foam capacity, stability, emulsifying activity and emulsion stability. More resistance to aggregation. Lowered viscosity (12)... 

The formation of complexes affects both particle-solvent and particle-particle interactions. The solubility of proteins may be increased by their electrostatic complexing with anionic polysaccharides. Formation of titration-complexes may increase protein solubility and inhibit protein precipitation at the lEP. Anionic polysaccharides can act as protective hydrocoUoids inhibiting aggregation and precipitation of like-charged dispersed protein particles, for example, of denatured proteins. This protective action also can increase the stability of protein suspensions and oil-in-water emulsions stabilized by soluble protein-anionic polysaccharide complexes. 

Considering stability to both aggregation and coalescence, the factors favoring emulsion stability can be summarized as follows ... 

Rousseau, D., Fat Crystals and Emulsion Stability, Food Res. Inti. 33 3-14 (2000). Boode, K., and P. Walstra, Partial Coalescence in Oil-Water Emulsions 1 Nature of Aggregation, Colloids Surf. A. 81 121-137 (1993). 

Alkaline hydrolysis of forskolin is inhibited in a lipid emulsion.550 Indomethacin in an oil-water gel is solubilized in the surfactant aggregates and stabilized against acid- and base-catalyzed hydrolysis.551... 

Sjoblom and his research team have probed the causes of emulsion stability in a series of North Sea crude oils and observed that emulsion stability correlates with asphaltene, wax, and resin/asphaltene ratio [11]. In their early work, they theorized that asphaltenes may aggregate through stacking interactions mediated by aromatic 7r-bond overlap to form lamellar structures that stabilize the emulsions. Moreover, they further observed... 

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