Sodium alginate

Sodium alginate is a natural gum, extracted from the cell walls of brown algae. It is a polysaccharide, specifically a linear copolymer with homopolymeric blocks of (1-4)-linked β-D-mannuronate (M) and its C-5 epimer α-L-guluronate (G) residues, respectively, covalently linked together in different sequences or blocks.

Production

The alginate is extracted from brown seaweed and is available in two forms, sodium alginate and calcium alginate. The process of extraction involves several steps, including washing, pressing, filtration, precipitation, and drying. The alginate is then converted into sodium alginate by adding sodium carbonate.

Properties

Sodium alginate has a number of unique properties which make it useful in a wide range of applications. It is capable of producing a gel without the need for heat, making it useful in food production and medical applications. It is also capable of absorbing large amounts of water, making it useful as a thickening agent.

Applications

Sodium alginate has a wide variety of uses, including food production, pharmaceuticals, and industrial applications.

Food Production

In food production, sodium alginate is used as a stabilizer, thickener, and emulsifier. It is also used in the production of gel-like foods, such as jelly and ice cream.

Pharmaceuticals

In the pharmaceutical industry, sodium alginate is used as a thickening agent for liquid medicines and as a stabilizer for oil-in-water emulsions. It is also used in the production of controlled-release medications.

Industrial Applications

In industrial applications, sodium alginate is used as a binder, thickening agent, and as a stabilizer. It is used in the production of paper, textiles, and in the manufacture of welding rods.

Health Effects

Sodium alginate is generally considered safe for consumption. However, excessive consumption can lead to gastrointestinal issues such as bloating and diarrhea.

See Also

• Alginic acid
• Alginate lyase
• Algin