Gums commercial

Like guar gum, commercial locust bean gum is not a pure galactomannan. It contains substances other than galactomannan (protein,... 

Fa.tMimetics. Existing fat mimetics are either carbohydrate-, ceUulosic (fiber)-, protein-, or gum-based. These are used in a wide variety of appHcations including baked goods, salad dressings, frozen desserts, meats, confections, and dairy products. Table 3 Hsts some of the commercially available fat mimetics. 

Gas must be commercially free of sand, dust, gums, and free Hquid. DeHvery temperature, 322.16 K deUvery pressure, 4.83 MPa. Ref. 8. 

The botanical gums represent a family of polysaccharides obtained from a wide variety of plant sources. They are subdivided into exudate gums, seed gums, and gums obtained by extraction of plant tissue. For a gum to be used in commercial quantities, it must be present in the tissues or be readily extractable in relatively pure form which limits the number of commercial botanical gums. 

Gum Arabic. Gum arable [9000-01-5] is a dried exudate from a species of the acacia tree found in various tropical and semitropical areas of the world. Most of the commercial gum comes from a single species, Jicacia Senegal. The largest producers are the RepubHc of Sudan and several other West African countries, with over 75% of the world s production coming from the Sudan. The best grade comes from Jicacia Senegal and about 90% of the Sudan s production is from this source the remainder comes Jicacia sejal... 

Although most seeds contain starch as the principal food reserve, many contain other polysaccharides and some have industrial utility. The first seed gums used commercially were quince, psyUium, flax, and locust bean gum. However, only locust bean gum is stiU used, particularly in food appHcations quince and psyllium gums are only used in specialized appHcations. 

Psyllium Seed Gum. PsyUium seed gum [8036-16-9] is derived from plants of the genus Plantago several species of which are used as commercial sources. However, most current production is from Plantago ovata grown in India. The gum is located in the coat which is removed by cracking. The gum is then extracted with boiling water and separated from the insoluble residue by filtration. It consists of mixtures of both neutral and acidic polysaccharides, the composition of which is species dependent (66). 

Larch Gum. Larch gum [37320-79-9] (larch arabinogalactan) is obtained by water extraction of the western larch tree, iLarix occidentalism the heartwood of which contains 5—35% on a dry wood basis. In the early 1960s, a countercurrent hot water extraction system was developed, and the gum was produced commercially by the St. Regis Paper Co. under the trade name Stractan. The potential production capacity of this gum is 10,000 t/yr based on the wood residues from the lumber industry. However, the product could not compete with gum arabic, and commercial production is now limited to small batches for a specific medical appHcation. 

Xanthan Gum. As a result of a project to transform agriculturally derived products into industrially usefiil products by microbial action, the Northern Regional Research Laboratories of the USDA showed that the bacterium TCanthomonas campestris - noduces a polysaccharide with industrially usefiil properties (77). Extensive research was carried out on this interesting polysaccharide in several industrial laboratories during the eady 1960s, culminating in commercial production in 1964. 

Only a minor proportion of the total lecithin that is potentially available in the vegetable processing industry is produced. If the phosphoHpids are not to be made into commercial lecithin, they may be left in the cmde oil or, if they are to be separated from the cmde oil as wet gum, they may be mixed into soybean meal for animal feed. 

Xanthan gum [11138-66-2] is an anionic heteropolysaccharide produced by several species of bacteria in the genus Aanthomonas A. campestris NRRL B-1459 produces the biopolymer with the most desirable physical properties and is used for commercial production of xanthan gum (see Gums). This strain was identified in the 1950s as part of a program to develop microbial polysaccharides derived from fermentations utilizing com sugar (333,334). The primary... 

Table 1 Hsts representative examples of capsule shell materials used to produce commercial microcapsules along with preferred appHcations. The gelatin—gum arabic complex coacervate treated with glutaraldehyde is specified as nonedible for the intended appHcation, ie, carbonless copy paper, but it has been approved for limited consumption as a shell material for the encapsulation of selected food flavors. Shell material costs vary greatly. The cheapest acceptable shell materials capable of providing desired performance are favored, however, defining the optimal shell material for a given appHcation is not an easy task.

Silicones are the subject of many reviews (1 8). Commercial products include fluids, filled fluids and gums, greases, resins and mbber (1,2). Various forms of sibcones and examples of appHcations are Hsted in Table 1. 

The processing methods for siHcone mbber are similar to those used in the natural mbber industry (59,369—371). Polymer gum stock and fillers are compounded in a dough or Banbury-type mixer. Catalysts are added and additional compounding is completed on water-cooled roU mills. For small batches, the entire process can be carried out on a two-roU mill. Heat-cured siHcone mbber is commercially available as gum stock, reinforced gum, partially filled gum, uncatalyzed compounds, dispersions, and catalyzed compounds. The latter is ready for use without additional processing. Before being used, sihcone mbber is often freshened, ie, the compound is freshly worked on a mbber mill until it is a smooth continuous sheet. The freshening process eliminates the stmcturing problems associated with polymer—filler interactions. 

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