Alginate salts

Mixed alginate salts Mixed catalysts Mixed cellulose ethers... 

While alginate salts with alkali metals such as sodium or potassium are soluble in water salts with divalent cations such as calcium, copper and zinc (Ca2+, Cu2+, and Zn2+, respectively) are insoluble in water. In this experiment, you will observe what happens when a drop of a sodium alginate solution is added to an aqueous solution of a divalent cation. The transformation from polymer solution to gel involves the concepts of polymer solubility, diffusion, and ion exchange. 

Sodium alginate is incompatible with acridine derivatives, crystal violet, phenylmercuric acetate and nitrate, calcium salts, heavy metals, and ethanol in concentrations greater than 5%. Low concentrations of electrolytes cause an increase in viscosity but high electrolyte concentrations cause salting-out of sodium alginate salting-out occurs if more than 4% of sodium chloride is present. 

The WHO has not specified an acceptable daily intake for alginic acid and alginate salts as the levels used in food do not represent a hazard to health. ... 

Demulcents are agents or preparations that protect the mucous membranes and relieve pain and irritation. They are thought to work by forming a protective film and are commonly incorporated into antacid preparations for protecting the gastric mucosa of the mouth. The most commonly used is alginic add or one of its alginate salts. 

Insoluble inserts are polymeric systems into which the drug is incorporated as a solution or dispersion. Ophthalmic inserts (ocuserts) have been reported using alginate salts, poly(A-vinyl pyrrol-idone), modified collagen, and hydroxyl propyl methyl cellulose. Ocufit is a silicone elastomer-based matrix that allows for the controlled release of an active ingredient over a period of at least 2 weeks. Osmotically controlled inserts have also been described, where release is by diffusion and is osmotically controlled. 

Alginates have interesting ion-exchange properties most monovalent counterions (except Ag ) form soluble alginate salts, whereas divalent and multivalent cations (except Mg " ) form gels or precipitates. The affinity was found to follow the order [60-63] ... 

Common/vernacular names Algin, salts of alginic acid(alginates), andparticularly sodium alginate. 

Algin occurs in all members of the class Phaeophjceae, brown seaweed, as a stmctural component of the cell walls in the form of the insoluble mixed calcium, magnesium, sodium, and potassium salt of alginic acid. 

Functional Blends. The term functional blend refers to various ingredient blends formulated to achieve a certain objective such as fat reduction. An example of this blend consists of water, partially hydrogenated canola oil, hydrolyzed beef plasma, tapioca flour, sodium alginate, and salt. This blend is designed to replace animal fat and is typically used at less than 25% of the finished product. Another functional blend is composed of modified food starch, rice flour, salt, emulsifier, and flavor. A recommended formula is 90% meat (with 10% fat), 7% added water, and 3% seasoning blend... 

The term alginate refers to the salt forms of alginic acid [9005-32-7] a copolymer of D-mannopyranosyluronic acid [56687-62-8] (1) and L-gulopyranosyluronic acid [56688-68-7] (2) residues. 

Sodium alginate [9005-38-3]. Freed from heavy metal impurities by treatment with ion-exchange resins (Na -form), or with a dilute solution of the sodium salt of EDTA. Also dissolved in 0. IM NaCl, centrifuged and fractionally ppted by gradual addition of EtOH or 4M NaCl. The resulting gels were centrifuged off, washed with aq EtOH or acetone, and dried under vacuum. [Buchner, Cooper and Wassermann J Chem Soc 3974 7967.]... 

Anionic hydrophilic Sodium chondroitinsulfate, sodium alginate, carboxymethyj cellulose, sodium polyacrylate, sodium hyaluronate Buffer or salt solution (e.g., 0.1 M NaNO,)... 

This is composed of the sodium and ealeium salts of alginic add formed into a powder or fibrous material and sterilized by autoelaving. It aids clotting by forming a sodium-caldum alginate complex in contact with tissue fluids, acting principally as a mechanical haemostat. It is relatively slowly absorbed and some residues may occasionally remain in the tissues. 

Alginate gels, formed chemically, do not melt upon heating and are stable up to the boiling point of water. They can be liquefied by chemical reactions that will convert the alginate into a soluble salt. 

Sodium alginate (algin) is one of the most widely used hydrocolloids for ice cream. It is supplied in several viscosity types. The lower viscosity material is recommended in order to prevent thick mixes. It is used at a level of 0.15 to 0.25%. It is added to mix at higher temperatures in order to minimize precipitation by calcium salts present in milk products. Sodium alginate is sensitive to high acidities often developed in some mixes and causes thickening. 

Most of the hydrocolloids listed for ice cream may be used in ices and sherbets. Gelatin is used a great deal. However, it makes overrun difficult to control and consequently it is used in conjunction with other hydrocolloids. A 225 Bloom gelatin is used at 0.4 to 0.5%. Sodium alginate is affected by acid and calcium salts and is not often used. Propylene glycol alginate is more resistant in this respect and is used at levels of 0.15 to 0.25%. Carrageenin is used in many blends. 

The hydrocolloids used stabilize this type of icing by their ability to form a gel or a highly viscous solution. Agar-agar, locust bean gum, sodium alginate (combined with a buffer and calcium salt), Irish moss extract, pectin, and karaya gum are hydrocolloids used. The finished icing may contain from 0.1 to 0.5% hydrocolloids. 

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