Xanthan thickener

Other thickeners used include derivatives of ceUulose such as methylceUulose, hydroxypropylmethylceUulose, and ceUulose gum natural gums such as tragacanth and xanthan (see Cellulose ethers Gums) the carboxyvinyl polymers and the poly(vinyl alcohol)s. The magnesium aluminum siHcates, glycol stearates, and fatty alcohols in shampoos also can affect viscosity. 

In addition to the normal problems of completely dissolving particles of water-thickening polymers, xanthan gum contains insoluble residues which decrease polymer injectivity. Various methods of reducing insolubles content and improving xanthan solution injectivity are available (80—87). None appears economically viable. Oxygen scavengers (88) and bactericides (77,89) are commonly used to stabili2e injected polyacrylamide and xanthan gum solutions (90—102). 

Surfactants evaluated in surfactant-enhanced alkaline flooding include internal olefin sulfonates (259,261), linear alkyl xylene sulfonates (262), petroleum sulfonates (262), alcohol ethoxysulfates (258,261,263), and alcohol ethoxylates/anionic surfactants (257). Water-thickening polymers, either xanthan or polyacrylamide, can reduce injected fluid mobiHty in alkaline flooding (264) and surfactant-enhanced alkaline flooding (259,263). The combined use of alkah, surfactant, and water-thickening polymer has been termed the alkaH—surfactant—polymer (ASP) process. Cross-linked polymers have been used to increase volumetric sweep efficiency of surfactant—polymer—alkaline agent formulations (265). 

For products intended to remain stable dispersions for an extended period, a particle size of 2 p.m or less is desirable. A thickening agent is usuaUy added after the reaction has been completed and the mixture is cooled in order to prevent settling and agglomeration. Examples of thickeners are guar gum, xanthan gum, and hydroxyethylceUulose. The final products are generaUy between 40 and 50% soUds, with a viscosity of 1500 5000 mPa-s(=cP). 

Xanthan gum is used as a thickener in sauces, as an agent in ice cream that prevents ice crystals from forming, and as a fat substitute that adds the mouth feel of fat without the calories. It is used in canned pet food to add cling. In pastry fillings, it prevents syneresis (weeping of the water in the filling), protecting the crispness of the crust. 

R. M. Hodge. Particle transport fluids thickened with acetylate free xanthan heteropolysaccharide biopolymer plus guar gum. Patent US 5591699,1997. 

Oleaginous bases consist of vegetable oil thickened with agents such as aluminum monostearate, colloidal silica, and xanthan gums. The lubricant properties of the oil make these formulations less adhesive than water bases. 

Both nonionic and anionic surfactants have been evaluated in this application (488,489) including internal olefin sulfonates (487, 490), linear alkylxylene sulfonates (490), petroleum sulfonates (491), alcohol ethoxysulfates (487,489,492). Ethoxylated alcohols have been added to some anionic surfactant formulations to improve interfacial properties (486). The use of water thickening polymers, either xanthan or polyacrylamide to reduce injected fluid mobility mobility has been proposed for both alkaline flooding (493) and surfactant enhanced alkaline flooding (492). Crosslinked polymers have been used to increase volumetric sweep efficiency of surfactant - polymer - alkaline agent formulations (493). 

Other natural polysaccharides used as thickening agents include gum arabic, gum tragacanth and xanthan gum, but these are of diminishing significance nowadays. 

Xanthan gum dissolves in cold water. A 1% solution has a pH between 6.1 and 8.1. It normally functions as a thickener but combines synergistically with locust bean gum to produce a very cohesive and elastic gel. Xanthan gum is used in making gluten-free bread but it is one of the few substances that can be used as a substitute for gum tragacanth. 

Bylaite, E., Adler-Nissen, J., and Meyer, A.S. Effect of xanthan on flavor release from thickened viscous food model systems, J. Agric. Food Chem., 53(9) 3577-3583, 2005. 

Stabilizers and Thickeners. Many food products receive their textural properties from a group of compounds known as hydrocolloids. Hydrocolloids fall into Iwo classes polysaccharides and proteins. They include loeust bean gum. guar gum, gum arabic. carrageenan, xanthan gum. cellulose. agar, starch, pectin, alginates, and gelatin. See also Stablizer. 

Xanthan gum, dextran Xanthomonas campestris, Leuconostoc mesenteroides Food, pharmaceutical, textile industries, useful for thickening, stiffening and setting properties... 

Vegetable gums and thickeners 407 Carrageenan Vegetable gums are failsafe. Guar and xanthan are used... 

Oatrim can be used in cheeses as a fat replacer.12 Other possible applications are in ice cream and frozen desserts, milk shakes, hot chocolate, instant-type breakfast drinks, cereals, salad dressings, soups, sauces and gravies. Oat starch in combination with oat hydrolysate or with xanthan gum has been used for thickening of sweet and sour sauces.18... 

Starch mixed with such polysaccharide gums as guar, xanthan, and locust bean are used as food thickeners, especially when a surfactant is added.1055 A composition of guar gum coated with starch has been patented for decreasing levels of cholesterol and glucose in blood.1057 Starch blended with achrodextrin, gum arabic, and sodium silicate is used as an adhesive for book binding.1058... 

Xanthan gum Thickener exhibits synergy with locust bean gum Polysaccharide Aerobic fermentation of Xanthomonas campestris... 

---