Information AboutCarrageenan |
| CATEGORIES ABOUT CARRAGEENAN | |
| edible thickening agents | |
| polysaccharides | |
| food additives | |
| iarc group 2b carcinogens | |
| personal lubricants | |
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PROPERTIES Carrageenans are large, highly flexible molecules which curl forming Helical structures. This gives them the ability to form a variety of different Gel s at room temperature. They are widely used in the food and other industries as Thickening and Stabilizing Agent s. A particular advantage is that they are Thixotropic — they thin under Shear Stress and recover their Viscosity once the stress is removed. This means that they are easy to pump but stiffen again afterwards. There are three main commercial classes of carrageenan:
Many red algal species produce different types of carrageenans during their developmental history. For instance, the genera ''Gigartina'' produces mainly Kappa carrageenans during its Gametophytic stage, and Lambda carrageenans during its Sporophytic stage. See Alternation Of Generations . All are soluble in hot water, but in cold water only the Lambda form (and the sodium salts of the other two) are soluble. When used in food products, carrageenan has the EU additive E-number E407 or E407a when present as "Processed eucheuma seaweed". Although introduced on an industrial scale in the 1930s, the first use was in China around 600 BC (where ''Gigartina'' was used) and in Ireland around 400 AD. The largest producer is the Philippines , where cultivated seaweed produces about 80% of the world supply. The most commonly used are Cottonii (''Kappaphycus alvarezii, K.striatum'') and Spinosum (''Eucheuma denticulatum''), which together provide about three quarters of the World production. These grow at sea level down to about 2 metres. The seaweed is normally grown on nylon lines strung between bamboo floats and harvested after three months or so when each plant weighs around 1 kg. The Cottonii variety has been reclassified as ''Kappaphycus cottonii'' by Maxwell Doty (1988), thereby introducing the genus ''Kappaphycus'', on the basis of the phycocolloids produced (namely kappa carrageenan). After harvest, the seaweed is dried, baled, and sent to the carrageenan manufacturer. There the seaweed is ground, sifted to remove impurities such as Sand , and washed thoroughly. After treatment with hot alkali solution (e.g. 5-8% potassium hydroxide), the Cellulose is removed from the carrageenan by Centrifugation and Filtration . The resulting carrageenan solution is then concentrated by Evaporation . It is dried and ground to specification. USES
Sexual lubricant and microbicide Although the researchers are optimistic and show that the products "block HPV infectivity in vitro, even when diluted a million-fold", they emphasize that "it would be inappropriate to recommend currently available products for use as topical microbicides" until further human tests are complete. (By comparison, similarly optimistic results were expected for HIV prevention by Cellulose Sulfate gels, based on early tests, but the clinical trials had to be halted when the gel was found to ''increase'' incidence of HIV infection.) Organization Halts Clinical Trial For Potential Microbicide For Preventing HIV Infection A clinical trial by Population Council examining whether a carrageenan-based product known as ''Carraguard'' is effective as a Topical Microbicide for blocking HIV infection in women was completed in March 2007. Results are expected at the end of 2007. While effectiveness trials have not been completed and side effects have not been ruled out, companies are already planning to capitalize on the discovery, such as Dreamspan naming their lubricant ''Carrageenan'' after its principal ingredient.Arizona Republic article about the development of Carrageenan. Dreamspan Product Innovation , manufacturer of Carrageenan HEALTH CONCERNS There is evidence from studies performed on s and Acid ity. The average carrageenan molecule weighs over 100,000 Da while poligeenans have a Molecular Weight of less than 50,000 Da . A scientific Committee working on behalf of the European Commission has recommended that the amount of degraded carrageenan be limited to a maximum of 5% (which is the limit of detection) of total carrageenan mass. Upon testing samples of foods containing high molecular weight carrageens, researchers found no poligeenan. Opinion of the Scientific Committee on Food on Carrageenan - 5 March 2003 A recent publication indicates that carrageenan induces inflammation in human intestinal epithelial cells in tissue culture through a Bcl10-mediated pathway that leads to activation of NFkappaB and IL-8. Carrageenan may be immunogenic due to its unusual alpha-1,3-galactosidic link that is part of its disaccharide unit structure. Consumption of carrageenan may have a role in intestinal inflammation and possibly inflammatory bowel disease, since Bcl10 resembles NOD2, mutations of which are associated with genetic proclivity to Crohn's Disease . SEE ALSO REFERENCES |
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