Carbohydrate Gums

Additional sources of acid contamination include carboxyl group in the cellulose, acidic carbohydrate gums, bleach and pulping chemical residues, and some constituents of coating colors. Acids may be introduced after the paper is manufactured by atmospheric contamination, particularly sulfur dioxide which is absorbed by the paper and, in the presence of moisture, will generate sulfuric acid. 

The essential ingredients in an emulsion polymerization are the water, monomer, surfactant, and free-radical source. Other ingredients are frequently added for a variety of reasons. Stabilizers, which are usually water-soluble high polymers or carbohydrate gums, are employed to control latex viscosity and freeze-thaw stability of products that are used in the latex form. 

There are a few minor wood-based chemical industries. After chestnut blight wiped out the American chestnut, U.S. tannin production essentially ceased. The main natural tannins, watde and quebracho, are now imported. High U.S. labor costs and the advent of synthetic tannins make re-establishment of a U.S. tannin industry unlikely. Tannins are used in oil-weU drilling muds. Tree exudates are a continuing wood-based chemical industry. Tree exudates include mbber, tme carbohydrate gums (eg, acacia gum), kinos (eg, the phenolic exudates from eucalyptus), balsams (eg, Storax from l iquidambar spp.), and many different types of oleoresins (mixtures of a soHd resin and a liquid essential oil). The most important oleoresin stiU collected in the United States is pine gum (rosin plus turpentine). 

Prado, B.M. Kim, S. Ozen, B.E. Mauer, L.J. Differentiation of carbohydrate gums and mixtures using Eourier transform infrared spectroscopy and chemometrics. J. Agric. Food Chem. 2005, 53 (8), 2823-2829. 

Synonyms Carbohydrate gum Cellulose hydroxypropyl methyl ether Cellulose 2-hydroxypropyl methyl ether HPMC Hypromellose Methyl hydroxypropyl cellulose MHPC Definition Propylene glycol ether of methyl cellulose Properties Wh. gran, powd. sol. in most polar soivs., cold water swells in water to produce a clear to opalescent vise, colloidal sol n. insol. in hot water and in anhyd. alcohol, ether, chloroform nonionic Toxicoiogy LD50 (IP, rat) 5200 mg/kg mildly toxic by IP route TSCA listed... 

Foods containing modified food starch, pectin, and carbohydrate gums as stabilizers and thickeners. 

Synonyms Carbohydrate gum Cellulose hydroxypropyl methyl ether Cellulose 2-hydroxypropyl methyl ether HPMC Hypromellose... 

After treatment with water, there was a weight loss of 9.27% for the non-treated fiber, indicating that a small amount of soluble extractives is removed with water. The soluble extractives removed by water are typically carbohydrates, gums, proteins and inorganic salts. Santiago [24] shows that hot water treatment removes part of the waste material in the coconut fiber, without removing the internal components of the fiber, thus avoiding alterations of the fiber properties. 

B. Mann, Identification of carbohydrate gums in dental cream by thin-layer chromatography, J. Chromatogr. 407 369-376 (1987). 

If we were limited to these two examples, it might be concluded that the commercial future of wood-based extractive industries is doubtful. On the other hand, natural rubber production has continued as a major activity in a number of countries in spite of all the attempts to replace it with synthetic substitutes. Carbohydrate gums and mucilages continue to be collected, refined, and utilized in applications unimagined only a few years ago. Almost all of the world s tall oil and sulfate turpentine that can be conveniently captured is sold to fractionators who convert it to a myriad of saleable products and intermediates (Chap. 10.1). 

It almost goes without saying that there may be a product that can be made only from a given wood or bark substrate. In that event, the substrate is the preferred raw material, and the financial risk from substitute raw materials is very low. While there are relatively few utilization schemes that fall into this category, some important examples are natural rubber, the naval stores industry, production of carbohydrate gums from acacia trees, essential oils from foliage, and so on. 

In terms of volume and value, the most significant wood-based extractives industries are natural rubber, resin and terpenes, carbohydrate gums, and tannins. The reasons for survival, growth, or decline in the future for each of these industries are quite different and are illustrative of the business principles described in the preceding section. 

Pectin A dry powder or a water solution of a carbohydrate gum used to make gels Prepaiabon of jolies and other types of gels. In an antidiorrheal remedy. Ljtde or no nutritional value, but used medicinaHy to lower blood chotesleiol. Citius pectin appears to be much more efiective than apple pectin in loweiing cholesterol. 

Carbamide Carbamide resin Carbamidic acid Carbamimidic acid. See Urea Carbenoxoione disodium Carbenoxolone, disodium saH Carbenoxoione sodium. See Disodium succinoyl glycyrrhetinate Carbinamine. See Methyiamine Carbinoi. See Methyl alcohoi CarbHol. See Ethoxydiglycol Carbitor acetate. See Ethoxydiglycol acetate Carbohydrate gum. See Hydroxypropyl methylcellulose... 

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