Lecithin emulsifier

Stabilization of margarine and other similar food emulsions is achieved by partial adsorption of solid fat particles (P -polymorphs) on to the water-oil interface, bridged by monomeric hydrophobic emulsifiers. The complex stabilization is achieved by wetting the oil phase by solid fat particles and emulsifiers (lecithins and monoglycerides of fatty acids). The concept was re-examined and reconsidered by Bergenstahl and coworkers (54, 55) and the mechanism was somewhat better elucidated. 

The incorporation of lecithin in different amounts (10-50% related to the triglyceride) did not influence the melting or crystallization temperature of the hard fat in the bulk phase neither in the nanoparticles but led to an accelerated polymorphic transition to the stable 6-modification particularly in the nanoparticles. No additional colloidal structures derived from the emulsifiers (lecithin and Solutol) could be detected in the aqueous phase by electron microscopy and the results of H- and P-NMR studies indicate that lecithin and Solutol are nearly completely attached to the particle surface. However, from the results it was also concluded that due to the redistribution of the lecithin from the lipid matrix and its enrichment in the particle interface, neither an increase in drug load (into the solid... 

Process catalysed by phospholipases. Soybean lecithin is a widely used natural emulsifier. Compared to synthetic emulsifiers, lecithin is inferior with respect to its emulsion stabilization potency. One of the ways to improve the stabilization properties of lecithin is to convert it to lysolecithin. By the loss of one of the fatty acids on the molecule, the hydrophilicity of the compound is generally improved, thus enhancing the stabilization of oil in water (OAV) types of emulsions. Such a transformation is performed industrially using phospholipases (Yamane, 1991). 

Chem. Descrip. Soya lecithin, polysorbate 80 CAS 8002-43-5 37200-49-0 EINECS/ELINCS 232-307-2 Uses Emulsifiable lecithin cosmetics emulsifier Properties Acid no. 16-27 iodine no. 80-90 sapon. no. 175-185 LEG 325 [Mosselman NV]... 

Lecithin is added to foods such as mayonnaise as an emulsifying agent to prevent the fat and water from sepa rating into two layers... 

Animal Feed. In animal feeds (1—3% lecithin) lecithin is an emulsifier wetting and dispersiag agent energy source antioxidant surfactant source of choline, organically combiaed phosphoms and iaositol and Hpotropic agent. It is used ia a milk replacer formula for calves (approximately 10,000 t of lecithin ate used for this purpose) and for veal production, ia mineral feeds, poultry feeds, fish foods, pet foods, and feeds for fur-beating animals (30). 

Gandy. In confections (1% lecithin) made with oil or fat, lecithin emulsifies and distributes fat ia caramels, nut britties, nougats, etc it also prevents fat separation and gteasiaess. It has a fixative action for flavors (35) (see Flavors and spices). Also, lecithin is an emulsifier and conditioning agent for chewing gum base. 

Chocolate (0.3—0.5% lecithin) lecithin is a wetting agent and emulsifier. It facihtates mixing, saves processiag time and power, saves cocoa butter, stabilizes viscosity, iacreases shelf life, counteracts moisture thickening, and aids release of molded goods (see Chocolate and cocoa). 

Cosmetics and Soaps, One to five percent lecithin moisturizes, emulsifies, stabilizes, conditions, and softens when used ia products such as skin creams and lotions, shampoos and hair treatment, and Hquid and bat soaps. Siace the iatroduction of Capture ia 1986, liposomes produced from phosphohpids ate commercially available worldwide (36,37). 

Food. Lecithin is a widely used nutritional supplement rich ia polyunsaturated fatty acids, phosphatidylcholine, phosphatidylethanolamine, phosphatidjhnositol, and organically combiaed phosphoms, with emulsifying and antioxidant properties (38). 

Ice Crea.m, Lecithin (0.15—0.5%) emulsifies, stabilizes, improves smoothness and melting properties, and counteracts sandiness ia storage. Lecithin is also used as an emulsifier ia whipped toppiags. 

Ma.rg a.nne, Lecithin (0.15—0.5%) is an emulsifier and an antispatteting and browning agent it improves frying properties and spreadabiUty and shortening action ia table margarine. It is also used ia bakers margarine. 

Edible Oils and Fats. lecithin (0.01—2%) is used as an emulsifier, wetting agent, and antioxidant it extends shelf hfe, especially of animal fats iacreases lubricity (shortening value) improves stabiUty of compouad shortenings and lowers cloud poiat of vegetable oils. 

Plant Protection. Lecithin (0.5—10%) and phosphohpid fractions ate used in fertilizers (qv), herbicides (qv), insecticides, and fungicides as emulsifiers or to increase the effectiveness of the active ingredient (45). In insecticides (0.5—5% lecithin), lecithin is used for improved emulsification, spreading, penetration, and adhesion (see Insectcontroltechnology). 

Textiles. Lecithin (0.2—0.5%) is used for emulsifying, wetting, softening, and conditioning especially in sizing and finishing. It imparts soft, smooth handle and also is used as a spray to reduce cotton (qv) dust. 

Lecithin (qv), a natural phosphoHpid possessing both hydrophilic and hydrophobic properties, is the most common emulsifier in the chocolate industry (5). The hydrophilic groups of the lecithin molecules attach themselves to the water, sugar, and cocoa soflds present in chocolate. The hydrophobic groups attach themselves to the cocoa butter and other fats such as milk fat. This reduces both the surface tension, between cocoa butter and the other materials present, and the viscosity. Less cocoa butter is then needed to adjust the final viscosity of the chocolate. 

Lecithin is widely used as an emulsifying agent, allowing oil and water to mix. It is used in ice creams, salad dressings, and cosmetics, and it is the main ingredient in nonstick cooking sprays. Lecithin is the emulsifier in egg yolks that allows the oil and water to mix to make mayonnaise. 

Preparation of lipid microspheres. The lipid microspheres (lipo-PGEj) with a diameter of 0.2 to 0.3 p m arc prepared from the drug, soybean oil and lecithin (Figure 1). The drug to be enclosed in the microspheres is first dissolved in soybean oil, and then emulsified with lecithin by a Manton-Gaulin homogenizer (7,2). 

Emulsifiers. Natural lecithin is one of the most widely used emulsifiers because it is metabolized in the body. However, type I allergic reaction to soybean lecithin emulsified in lipid solutions has been observed [195], Among the synthetic emulsifying agents, block copolymers of polyoxyethylene-polyoxypropylene (poloxamer) have attracted increasing interest for parenteral emulsions. Other examples of emulsifiers commonly found in parenteral formulations are given in Table 9 [190]. 

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