In emulsification

Of the cations (counterions) associated with polar groups, sodium and potassium impart water solubiUty, whereas calcium, barium, and magnesium promote oil solubiUty. Ammonium and substituted ammonium ions provide both water and oil solubiUty. Triethanolammonium is a commercially important example. Salts (anionic surfactants) of these ions ate often used in emulsification. Higher ionic strength of the medium depresses surfactant solubihty. To compensate for the loss of solubiUty, shorter hydrophobes ate used for appHcation in high ionic-strength media. The U.S. shipment of anionic surfactants in 1993 amounted to 49% of total surfactant production. 

P. Marie, J.M. Perrier-Cornet, and P. Gervais Influence of Major Parameters in Emulsification Mechanisms Using a High-Pressure Jet. J. Pood Eng. 53,43 (2002). 

No generalities seem justified regarding the relationship between concentration of emulsifier and oil deposit obtained. An increase in the concentration of certain emulsifiers has been found to increase the oil deposit, while in other cases the reverse has been true. It is clear that both the individual characteristics of the emulsifier and the concentration used affect deposit, but, in spite of the extensive literature on the role of emulsifiers in emulsification and deposition, no satisfactory method of evaluating emulsifiers for spray oils other than by actual trial imder field conditions has been found. A rather complete discussion of emulsifiers and the principles involved in emulsification is given in the work of Sutheim (21),... 

Schneider H, Roth T. Emulsification In Food Processing (in German). Course in Emulsification, University Karlsruhe/Germany, 1996 XIII-1/18. 

Lactalbumin is an insoluble whey protein product produced by heating whey to high temperatures ( > 90 C) to denature and render the proteins insoluble when adjusted to isoelectric conditions by the addition of acid. These proteins offer little functionality in emulsification applications. 

Several detailed discussions have described the complex theories of emulsion technology (1, 2, > 1 ) To summarize these theories, emulsifiers are essential for emulsion formation and stabilization to occur these surface-active compounds reduce the surface and interfacial tensions between two immiscible liquids, but this property accounts for only part of the mechanisms at work in emulsification. Three separate mechanisms that appear to be involved in formation of a stable emulsion include ... 

To remove lipids, sample extracts are frequently also partitioned with n-hexane (25, 33-35, 37, 40, 43, 45, 47, 49, 50, 53-57, 62), petroleum ether (31, 38, 63), isooctane (36, 41, 48), or toluene (26, 58, 59, 61). Use of n-toluene is not recommended, however, in chloramphenicol and florfenicol analysis, because these drugs have the tendency to transfer into toluene to some extent during the partitioning process. As an alternative to the classic liquid-liquid partitioning cleanup, some workers in the field (24, 26, 34, 58, 59) have suggested use of diatomaceous earth columns as another option of a liquid-liquid partitioning process that offers substantial reduction in emulsification problems and, thus, allows a high recovery increase. 

Shear A strain resulting from applied forces that cause or tend to cause contiguous parts of a body to slide relative to one another in direction parallel to their plane of contact. In emulsification and suspensions, the strain produced upon passing a system through a homogenizer or other milling device. 

IN EMULSIFICATION, ONE LIQUID IS DISPERSED IN ANOTHER. EMULSIONS CAN BE TEMPORARY OR PERMANENT. 

Because mineral seal oils differ in emulsification characteristics, it is necessary to modify the formulation to achieve optimum performance. The best formula can be determined by running a ladder of formulas. Typical examples are ... 

The exercise of preparing emulsions using oils-mixed additives is well described in Emulsification and Polymerization of Alkyd Resins (Gooch 1980, 2002), although without the addition of acidic or cationic agents for the purpose of inhibiting or destroying bacteria. 

The fast progress in microengineering and semiconductor technology led at the development of microchannels, that Nakajima et al. applied in emulsification technology [12]. 

The adsorption of surfactants at the liquid/air interface, which results in surface tension reduction, is important for many applications in industry such as wetting, spraying, impaction, and adhesion of droplets. Adsorption at the liquid/liquid interface is important in emulsification and subsequent stabilization of the emulsion. Adsorption at the solid/liquid interface is important in wetting phenomena, preparation of solid/liquid dispersions, and stabilization of suspensions. Below a brief description of the various adsorption phenomena is given. 

Fig. 51 Process equation in emulsification with jet emulsifier according to Fig. 50 from [75].The fitting line corresponds to the eq. (12.75).

There is a vast body of diblock copolymer studies since block choice can be such that they resemble amphiphilic surfactants. For the sake of brevity, we will skip them. Instead, we present an interesting case of triblock copolymers of poly(ethylene oxide), PEO, and poly(propylene oxide), PPO, commonly known by one of its trade names, Pluronics [117]. They have been used as non-ionic surfactants for a variety of applications such as in emulsification and dispersion stabilization. In aqueous solutions, these copolymers form micelles, and there exists a well-defined critical micelle concentration that is experimentally accessible. Several groups have investigated colloidal suspensions of these polymers [118-122], The surface properties of the adsorbed monolayers of the copolymers have been reported with respect to their structures and static properties [123-126]. 

The role of surface films in emulsification.111 Emulsions, or dispersions of one liquid in another, are of two types. One consists of a very dilute dispersion of small droplets of oil in water, in the stabilization... 

In meat emulsions, a specific soluble fraction of proteins was shown to function as the key emulsifier (22). However, Lin et al. (15) showed that sunflower meal was superior to soybean and sunflower protein concentrates or isolates in emulsification capacity. These authors suggest that nonprotein constituents of seeds may contribute to the formation of emulsions and aid in the formation of whipped foams. 

To this point, we have considered the interaction of nonionic surfactants within the framework of the mathanatical model. The activity and character of anionics in emulsification is complicated by the ionization steps which an anionic surfactant may take when exposed to salt solutions. For instance, in a dialkyl metallic salt, there are three compounds which may exist in various concentrations, depending ipon the ionic strength of the salt solution which, in turn, would exhibit, at least, three different HLB nuiiibers. To address the problem of generating Cohesive Energy Density parameters for the anionic hydrophiles, certain standardized assunptions... 

As shown by these results, very reasonable predictions can be tnade regarding surfactants in emulsification using the mathe-niatical approach described. 

The influence of the vessel size in the preparation of emulsions under ultrasonic energy in discrete systems has been established in terms of parameter R, which is the ratio of the height of the liquid-liquid mixture in the vessel to the diameter of the vessel. Two cylindrical vessels of different size (specifically with an R value of 1 and 2.5) were used under the same working conditions. Similar to the tip diameter, the differences in emulsification efficiency between the two vessels were small at a high (93 W) or very low (15 W) ultrasonic power. On the other hand, at 33 and 63 W, the efficiency was higher for the vessel with R= 1 viz. a cylindrical vessel) [56],... 

A suspended liquid drop forms a sphere, because this shape has minimum surface area (hence minimum interfacial free energy) for a given volume area is related to the cube of droplet radius. Distortion is a flow shear effect, depending on droplet cross-section, related to the square of the radius. At large diameters, shear forces are greater than interfacial tension forces, droplets are distorted into cylinders, and subdivision occurs. Droplet radius decreases, until the interfacial tension forces balance (or exceed) shear forces, and further division stops. In emulsification experiments in which the amount of mixing energy is constant and y... 

The composition of cetostearyl alcohol from different sources may vary considerably. The composition of the minor components, typically straight-chain and branched-chain alcohols, varies greatly depending upon the source, which may he animal, vegetable, or synthetic. This has been reported in the literature to impart differences in emulsification behavior, particularly with respect to emulsion consistency or stahi-lity. ... 

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