Emulsifier characteristics

Sanchez, C.C., Rodriguez Patino, J.M. (2005). Interfacial, foaming and emulsifying characteristics of sodium caseinate as influenced by protein concentration in solution. Food Hydrocolloids, 19, 407 116. 

The HLB is an indicator of the emulsifying characteristics of an emulsifier, but not its efficiency. Thus, while all emulsifiers having a high HLB will tend to promote O/W emulsions, there will be a considerable variation in the efficiency with which those emulsifiers act for any given system. For example, mixtures of surfac-... 

There have been a limited number of studies on the effects of enzymic modification of protein concentrates on functional properties other than solubility. Studies on functional properties, as modified by enzymic treatments, emphasize foam formation and emulsifying characteristics of the hydrolysates. Treatment of chicken egg albumen alters the functional properties of the egg proteins in terms of foam volume and stability and the behavior of the proteins in angel food cakes (25). Various proteolytic enzymes were used to degrade the egg albumen partially. However, proteolytic enzyme inhibitors indigenous to the egg proteins repressed hydrolysis of the egg proteins compared with casein. 

Spinelli et al. (14) determined the emulsion stability and emulsion capacity of polypeptides recovered from hydrolysates of fish myofibrillar protein using hexametaphosphate. In general the emulsion capacity and emulsion stability increased through 30 min of proteolysis but then declined. Even the unhydrolyzed protein-phosphate complex yielded better emulsion stability and capacity values compared with sodium caseinate. The effect of the residual hexametaphosphate in the hydrolysate conceivably could have a beneficial effect on emulsifying characteristics of the modified fish myofibrillar proteins. 

Uruakpa FO, Arntfield SD. 2005. Emulsifying characteristics of commercial canola protein-hydrocolloid systems. Food Research Ini 38 659-672. 

Aqueous media, such as emulsion, suspension, and dispersion polymerization, are by far the most widely used in the acryUc fiber industry. Water acts as a convenient heat-transfer and cooling medium and the polymer is easily recovered by filtration or centrifugation. Fiber producers that use aqueous solutions of thiocyanate or zinc chloride as the solvent for the polymer have an additional benefit. In such cases the reaction medium can be converted directiy to dope to save the costs of polymer recovery. Aqueous emulsions are less common. This type of process is used primarily for modacryUc compositions, such as Dynel. Even in such processes the emulsifier is used at very low levels, giving a polymerization medium with characteristics of both a suspension and a tme emulsion. 

Hydration water, fat, and flavor binding gelation emulsifying foaming and whipping characteristics vary among different soy protein products and complete substitution of animal proteins by these products is not always possible (114). 

Od-in-water based hairdressings offer good spreading characteristics, have a less greasy feel, and are more easdy rinsed than water-in-od forms. Mineral od is found in these products, although natural and synthetic ods have been used. The typical od-in-water emulsifiers are used in preparing these emulsions. 

Ice Crea.m, Ice cream is a frozen food dessert prepared from a mixture of dairy iugredients (16—35%), sweeteners (13—20%), stabilizers, emulsifiers, flavoriug, and fmits and nuts (qv). Ice cream has 10—20% milk fat and 8—15% nonfat solids with 38.3% (36—43%) total soHds. These iugredients can be varied, but the dairy ingredient soHds must total 20%. The dairy iugredients are milk or cream, and milk fat suppHed by milk, cream butter, or butter oil, as well as SNF suppHed by condensed whole or nonfat milk or dry milk. The quantities of these products are specified by standards. The milk fat provides the characteristic texture and body iu ice cream. Sweeteners are a blend of cane or beet sugar and com symp soHds. The quantity of these vary depending on the sweetness desired and the cost. 

Physical Form. Eor compounders, physical form is an important characteristic. They prefer sohd, free-flowing, nondusty materials whereas polymer manufacturers prefer materials that are Hquid and easily emulsified. Undesirable are semicrystalline materials which may stratify during storage. Also, substances to be avoided are highly viscous Hquids and low melting resins which block upon storage. 

Mineral acids are used as catalysts, usually in a concentration of 20— 40 wt % and temperatures of 30—60°C. An efficient surfactant, preferably one that is soluble in the acid-phase upon completion of the reaction, is needed to emulsify the a-pinene and acid. The surfactant can then be recycled with the acid. Phosphoric acid is the acid commonly used in the pine oil process. Its mild corrosion characteristics and its moderate strength make it more manageable, especially because the acid concentration is constandy changing in the process by the consumption of water. Phosphoric acid is also mild enough to prevent any significant dehydration of the alcohols formed in the process. Optimization of a process usually involves considerations of acid type and concentration, temperature, surfactant type and amount, and reaction time. The optimum process usually gives a maximum of alcohols with the minimum amount of hydrocarbons and cineoles. 

Many of the surfactants made from ethyleneamines contain the imidazoline stmcture or are prepared through an imidazoline intermediate. Various 2-alkyl-imidazolines and their salts prepared mainly from EDA or monoethoxylated EDA are reported to have good foaming properties (292—295). Ethyleneamine-based imida zolines are also important intermediates for surfactants used in shampoos by virtue of their mildness and good foaming characteristics. 2- Alkyl imidazolines made from DETA or monoethoxylated EDA and fatty acids or their methyl esters are the principal commercial intermediates (296—298). They are converted into shampoo surfactants commonly by reaction with one or two moles of sodium chloroacetate to yield amphoteric surfactants (299—301). The ease with which the imidazoline intermediates are hydrolyzed leads to arnidoamine-type stmctures when these derivatives are prepared under aqueous alkaline conditions. However, reaction of the imidazoline under anhydrous conditions with acryflc acid [79-10-7] to make salt-free, amphoteric products, leaves the imidazoline stmcture essentially intact. Certain polyamine derivatives also function as water-in-oil or od-in-water emulsifiers. These include the products of a reaction between DETA, TETA, or TEPA and fatty acids (302) or oxidized hydrocarbon wax (303). The amidoamine made from lauric acid [143-07-7] and DETA mono- and bis(2-ethylhexyl) phosphate is a very effective water-in-od emulsifier (304). 

Dried blends of whole egg and yolk with carbohydrates have sucrose or com symp added to the Hquids before spray-drying. Such carbohydrates (qv) preserve the whipping properties of whole egg and yolk by keeping the fat in an emulsified state. Com symp also gives anticaking characteristics, better flowabiHty, and improved dispersibiHty in water. Dried blends of egg and carbohydrate function weU in emulsified, as weU as unemulsified, sponge cakes. 

Vmulsifier Type. The manufacturers of NBR use a variety of emulsifiers (most commonly anionic) for the emulsion polymerisation of nitrile mbber. When the latex is coagulated and dried, some of the emulsifier and coagulant remains with the mbber and affects the properties attained with the mbber compound. Water resistance is one property ia particular that is dependent on the type and amount of residual emulsifier. Residual emulsifer also affects the cure properties and mold fouling characteristics of the mbber. 

The Karr column is particularly well suited for systems which tend to emulsify since its uniform shear characteristics tend to minimize emulsion formation. It is also particularly well suited for corrosive systems (since the plates can be constructed of non-metals) or for systems containing significant solids (due to its large open area and hole size on the plates). Slurries containing up to 30 percent solids have been successfully processed in Karr columns. 

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