Sorbitan monostearate

Sorbitan monostearate is an ester of sorbitol and stearic acid. The sorbitol end of the molecule is highly soluble in water. The stearic acid end is soluble in fats. These properties allow the molecule to excel at making emulsions of oil and water. 

Sorbitan monostearate is used as an emulsifying agent in cake mixes, icings, baked goods, puddings, imitation whipped cream, hemorrhoid creams, and creams to treat dry skin. It is often used with polysorbate 80. 

Similar molecules can be made using other fatty acids, such as the shorter-chained lauric acid. 

An emulsion is a mixture of oil and water. Some emulsions, such as butter and margarine, have tiny droplets of water in the oil. Others, like cream or mayonnaise, are droplets of oil in water. 

The choice of emulsifier has a large part to play in which kind of emulsion you get. Emulsifiers that are soluble in water generally have shorter chains of fats. These make emulsions of oil in water. Emulsi- 

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Sorhita.n nd Sorbitol Esters. This group of emulsifiers is formed from the reaction of sorbitan and stearic acid. Sorbitan monostearate is often used in combination with polysorbate in ice cream, imitation dairy products, and baking appHcations (36). 

Emulsions of fatty- and petroleum-based substances, both oils and waxes, of the o/w type are made by using blends of sorbitan fatty esters and their poly(oxyethylene) derivatives. Mixtures of poly(oxyethylene(20)) sorbitan monostearate (Polysorbate 60) and sorbitan monostearate are typical examples of blends used for lotions and creams. Both sorbitan fatty acid esters and their poly(oxyethylene) derivatives are particularly advantageous in cosmetic uses because of their very low skin irritant properties. Sorbitan fatty ester emulsifiers for w/o emulsions of mineral oil are used in hair preparations of both the lotion and cream type. Poly(oxyethylene(20)) sorbitan monolaurate is useflil in shampoo formulations (see Hairpreparations). Poly(oxyethylene) sorbitan surfactants are also used for solubilization of essential oils in the preparation of colognes and after-shave lotions. 

Ethoxylated Anhydrosorbitol Esters. Ethoxylation of sorbitan fatty acid esters leads to a series of more hydrophilic surfactants (Table 19). All hydroxyl groups of sorbitan can react with ethylene oxide. The stmcture of the principal component of a nominal polyoxyethylene (20) sorbitan monostearate illustrates the composition of these products, where w x y z = 20. 

A series of sorbitol-based nonionic surfactants are used ia foods as water-ia-oil emulsifiers and defoamers. They are produced by reaction of fatty acids with sorbitol. During reaction, cycHc dehydration as well as esterification (primary hydroxyl group) occurs so that the hydrophilic portion is not only sorbitol but also its mono- and dianhydride. The product known as sorbitan monostearate [1338-41 -6] for example, is a mixture of partial stearic and palmitic acid esters (sorbitan monopalmitate [26266-57-9]) of sorbitol, 1,5-anhydro-D-glucitol [154-58-8] 1,4-sorbitan [27299-12-3] and isosorbide [652-67-5]. Sorbitan esters, such as the foregoing and also sorbitan monolaurate [1338-39-2] and sorbitan monooleate [1338-43-8], can be further modified by reaction with ethylene oxide to produce ethoxylated sorbitan esters, also nonionic detergents FDA approved for food use. 

Processing Aids. Stearic acid [57-11-4] or other fatty acids and/or metal soaps of fatty acids are added to reduce shear degradation and mill sticking during mixing. Sorbitan monostearate (ICI s Span 60) is one of the best processing aids to reduce mill sticking. 

The suspension polymerization of 65% acrylamide aqueous solution dispersed in n-hexane (aqueous phase -hexane = 1 5) in the presence of a stabilizer (sorbitan monostearate, 1.4% with respect to -hexane) and an initiator (2,2 -azo-bis-A/, A/ -dimethyleneisobutylamide chloride) carried out at 65°C for 3 h, with subsequent holding at 110°C, yields a powdered product with the granule size of 0.5 mm, while the addition of Na2S04... 

Sweet N Low. See saccharin syneresis, 102-103 synthetic wax. See sorbitan monostearate syrups, 115... 

The stability characteristics of two different antiperspirant lotion systems were compared. Sample 1 represented an aqueous emulsion containing an aluminum salt. The internal phase consisted of stearyl alcohol and ethylene oxide reaction products, polyoxyethylene sorbitan monostearate and polyoxyethylene sorbitan tristearate. Methylcellulose was used as a stabilizer and bodying agent. Sample 2 represented a dispersion of magnesium aluminum silicate in an aqueous system containing aluminum ions. Because of its com-... 

Sorbitan monolaurate, 4 710 Sorbitan monooleate, 4 710 Sorbitan monopalmitate, 4 710 Sorbitan monostearate, 4 709 Sorbitan sequioleate... 

E 434 Polyoxyethylene sorbitan monopahnitate (polysorbate 40) E 435 Polyoxyethylene sorbitan monostearate (polysorbate 60)... 

Sorbitan monolaureate Sorbitan monooleate Sorbitan monopalmitate Sorbitan monostearate Sorbitan tristearate Stannous chloride Stearyl tartrate Succinic acid Sucroglycerides... 

Waxes of melting point 57-60°C are used with an emulsifying agent based on sorbitan monostearate or ethoxylated sorbitan monostearate [2]. The properties of a commercial product are given in Table 4.4 [5]. 

Low-molecular-weight surfactants ( emulsifiers ) are important ingredients in food products. The types of surfactants most commonly studied in food colloids research are phospholipids (lecithin), mono/diglycerides (particularly glycerol monostearate), polysorbates (Tweens), sorbitan monostearate or monooleate (Spans), and sucrose esters. These small lipid-based amphiphiles can typically lower the interfacial tension to a greater extent than the macromolecular amphiphiles such as proteins and certain gums (Bos and van Vliet, 2001). 

Sulconazole nitrate Exelderm Stearyl alcohol, cetyl alcohol, polysorbate 60, sorbitan monostearate, and PEG-100 stearate None... 

Ciclopiroxolamine Loprox Cetyl alcohol, steryl alcohol, polysorbate 60 NF, sorbitan monostearate Benzyl alcohol NF... 

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