Seaweed gums

There are two general types of seaweed gums of commercial importance, the brown and the red algae (Figure 6) ( I). 

Properties Seaweed gum (a natural phycocolloid) available as an odorless white powder, soluble in warm water. It form gels at low concentrations. Reputed to be more stable to heat and acids than other vegetable gums. Available in the form of salts. 

Their properties are similar to those of seaweed gums and the term is often applied to aqueous suspensions or solutions of gums and gelatinised starches. 

They represent fast renewable resource that could partially compensate restricted mass of plant polysaccharides. Their production is a matter of days while plants life cycles last months or years, being the production cycle usually seasonal. Microbial production is especially important in nonproducing areas of the world freeing them from exclusive reliance on the importation of plant and seaweed gums. 

KINDS OF FIBER. Fiber may be obtained from diverse sources, such as grains, vegetables, fruits, nuts, seaweed, gum trees, and the laboratory of the organic chemist. Therefore, it is worthwhile to consider the plant constituents that comprise most of the fiber in the human diet. 

Detergent Methods. The neutral detergent fiber (NDF) and acid detergent fiber (ADF) methods (2), later modified for human foods (13), measure total insoluble plant cell wall material (NDF) and the cellulose—lignin complex (ADF). The easily solubilized pectins and some associated polysaccharides, galactomaimans of legume seeds, various plant gums, and seaweed polysaccharides are extracted away from the NDF. They caimot be recovered easily from the extract, and therefore the soluble fiber fraction is lost. 

The viscosity of natural gums, such as cellulose gums, mannogalactans, seaweed, pectin, locust bean gum, guar gum, and tragacanth has important industrial applications in the food, pharmaceutical, cosmetic, textile, adhesives, and paint fields. The characteristics of viscosity are related to specific uses and to the economics of the process. 

Deoxy-L-galactose (L-fucose) HO H H HO HaC—C—C—C—C-—CHO H HO HO H plant gums seaweeds blood polysaccharides sea-urchin eggs frog-spawn mucin... 

Because of their large interfacial area, emulsions are basically unstable. In order to produce a stable emulsion, a surfactant is mostly needed. The surfactants are adsorbed at the oil-water interface, forming a link between the two phases of different polarity. For this purpose, a wide variety of emulsifying agents is currently available. Polysaccharides such as arabic gum, tragacanth, Karaya gum, and different seaweed carbohydrate polymers have been employed. They, however, show considerable batch-to-batch variations and might support microbial growth. 

Agar. This gum is extracted from certain marine algae belonging to the class Rhodophyceae, red seaweed, which abound off the coasts of Japan, Mexico, Portugal, and Denmark. Important species include Gelidium cartilagineum and Gracilaria confervoides. 

Seaweed [FOOD ADDITIVES] (Vol 11) agarose from [ELECTROSEPARATIONS - ELECTROPHORESIS] (Vol 9) gums from [GUMS] (Vol 12) mineral nutrients source [MINERAL NUTRIENTS] (Vol 16) plant growth regulators fiom [GROWTH REGULATIONS - PLANT] (Vol 12) source ofdietary fiber [DIETARY FIBER] (Vol 8)... 

A colorless or slightly yellow solid occurring in filamentous, granular, and powdered form. Forms a viscous cnlloidal solution with water, insoluble in alcohol, ether, and chloroform. It is extracted from brown seaweeds. The gum is used as a thickener, stabilizer, and emulsifier in foods, especially ice cream. Also used in boiler compounds, pharmaceuticals, textile printing, cement compositions, paper coatings, and in some water-base paints. 

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