CAS number: 9000-07-1
EC number: 232-524-2
E407 (Carrageenan) are used in a wide range of industries, especially the food industry, where their gelling qualities and viscointensifying properties are greatly valued. The structure of E407 (Carrageenan) has a major role when it comes to characteristics and properties. Kappa and Iota E407 (Carrageenan) have very similar structures and therefore share many properties. These polymers have a backbone of galactose but differ in the proportion and location of ester sulfate groups and the proportion of 3,6-anhydrogalactose. Kappa E407 (Carrageenan) is able to interact synergistically with other gums, such as locust bean gum and konjac mannan, to modify further the gel texture.
E407 (Carrageenan) ; E407 (Carrageenan) gum; Chondrus;3,6-Anhydro-D-galactan; Aubygel; Aubygum; Burtonite; Carastay; Carrageen; Carrageenin; Carragheanin; Carragheen; Carraguard; Chondrus; Coreine; Eucheuma spinosum gum; Galozone; Gelcarin; Gelozone; Genugel ; Genuvisco; Gum Chrond; Gum E407 (Carrageenan); Gum chon; Irish moss extract; Irish moss gelose; Killeen; Lygomme; Marine Colloids; Pellugel; Satiagel; Satiagum; Seakem carrageenin; Viscarin E407 (Carrageenan) ; iota E407 (Carrageenan) ; iota-E407 (Carrageenan) ; kappa E407 (Carrageenan) ; kappa-E407 (Carrageenan) ; lambda E407 (Carrageenan) ; lambda-E407 (Carrageenan) ; thickener, stabiliser, gelling agent, emulsifier
E407 (Carrageenan) are commercially important hydrophilic colloids (water-soluble gums) which occur as matrix material in numerous species of red seaweeds (Rhodophyta) wherein they serve a structural function analogous to that of cellulose in land plants. Chemically they are highly sulfated galactans. Due to their half-ester sulfate moieties they are strongly anionic polymers. In this respect they differ from agars and alginates, the other two classes of commercially exploited seaweed hydrocolloids. Agars, though also galactans, have little half-ester sulfate and may be considered to be nonionic for most practical purposes. Alginates, though anionic, are polymers of mannuronic and guluronic acids and as such owe their ionic character to carboxyl rather than sulfate groups. In this respect alginates are more akin to pectins, found in land plants, than to the other seaweed hydrocolloids.
E407 (Carrageenan) is a hydrocolloid extracted from some red seaweeds belonging to the Eucheuma (kappaphycus), Chondrus, Gigartina and Hypnea species. It is used in a wide variety of applications in the food industry as a thickening, gelling, stabilizing and suspending agent in water and milk systems. E407 (Carrageenan) is a multifunctional ingredient and it behaves differently in water and in milk systems. In water it shows typical hydrocolloid properties of thickening and gelling, while in milk systems it also has the property of reacting with proteins to furnish additional stabilizing abilities.
E407 (Carrageenan) has a unique ability to form a wide variety of gel textures at room temperature: rigid or elastic, clear or turbid, tough or tender, heat stable or thermally reversible, low or high melting/gelling temperatures. It may also be used as a suspending, gelling, emulsifying, stabilizing and water retaining agent in other industrial applications.
E407 (Carrageenan) is obtained from several kinds and species of seaweeds belonging to the Rodophyceae class. The E407 (Carrageenan) content of commercial seaweeds varies from 20% to 40% of dry weight, depending on the seaweed species and the sea conditions, such as luminosity, nutrients, water temperature and oxygenation. Seaweeds of different species and sources produce different types of E407 (Carrageenan) such as kappa, iota and lambda. Some species of seaweed may produce a mixed type E407 (Carrageenan) such as kappa/iota, kappa/lambda or iota/lambda.
The species that produce kappa-type E407 (Carrageenan) are Kappaphycus Alvarezii (former Eucheuma Cottonii) and Hypnea Musciformis. The specie that produces iota-type E407 (Carrageenan) is Eucheuma Denticulatum (former Eucheuma Spinosum). The species that produce lambda type E407 (Carrageenan) generally belong to the Gigartina species. Some species like Chondrus Crispus and Gigartina skottsbergii produce mixed type E407 (Carrageenan) kappa/lambda or kappa/iota.
Seaweeds are usually harvested manually by fishermen in low depths at low tides or by diving using appropriate equipment. After being harvested, seaweeds are placed under the sun to dry until they reach a humidity level that is ideal for processing. Kappaphycus Alvarezii (Cottonii) and Eucheuma Denticulatum (Spinosum) seaweeds have been successfully cultivated on a commercial scale in the Philippines, Indonesia and Tanzania. Chondrus and Gigartina skottsbergii are obtained respectively from natural seaweed beds in the North Atlantic and in Chile.
E407 (Carrageenan) is located in the cell wall and intercellular matrix of the seaweed plant tissue. It is a high molecular weight polysaccharide with 15% to 40% of ester-sulfate content. It is formed by alternate units of D-galactose and 3.6 anhydro-galactose (3.6-AG) joined by α-1,3 and β-1,4 –glycosidic linkage. The primary differences which influence the properties of kappa, iota and lambda E407 (Carrageenan) type are the number and position of ester sulfate groups as well as the content of 3.6-AG. Higher levels of ester sulfate means lower solubility temperature and lower gel strength. Kappa type E407 (Carrageenan) has an ester sulfate content of about 25 to 30% and a 3,6-AG content of about 28 to 35%. Iota type E407 (Carrageenan) has an ester sulfate content of about 28 to 30% and a 3,6-AG content of about 25 to 30%. %. Lambda type E407 (Carrageenan) has an ester sulfate content of about 32 to 39% and no content of 3,6-AG.
E407 (Carrageenan) may be refined or semi-refined according to the production process. Production process for semi-refined E407 (Carrageenan) is always the same. For refined E407 (Carrageenan), there are three methods used in the industry: Drum Drying, Alcohol Precipitation, and Gel Press.
The uses of E407 (Carrageenan) are concentrated in the food industry. E407 (Carrageenan) applications are generally divided into milk based systems, water based systems and beverages. However, there are many other applications for E407 (Carrageenan) in a large variety of industrial applications. E407 (Carrageenan) has many functions according to its uses and applications: gelling, thickening, emulsion stabilizing, protein stabilizing, particle suspension, viscosity control and water retention are just a few.
E407 (Carrageenan) are a specialized category of hydrocolloids that originate from red seaweed (Rhodophycae). E407 (Carrageenan) in its various forms provides the physical characteristics food scientists need when formulating food and beverage products that require gelling or added viscosity. The use of E407 (Carrageenan) in food dates back to approximately 400 A.D. in Ireland. Early Irish cooks discovered they could extract a thickener similar to E407 (Carrageenan) from Irish moss. Since the 1970s, food and beverage companies have discovered that E407 (Carrageenan) is useful for its superior gelling and thickening properties. It is these qualities that make it useful for use in frozen desserts, dairy- or soy-based beverages, baked goods and even formed proteins.
E407 (Carrageenan) can either be harvested directly from seaweed beds in the ocean or farmed in controlled settings. Typical harvesting areas include the Americas, Europe and Asia, including China, Japan, Korea and Philippines. Depending on the type of water and growing conditions, unique species will provide different characteristics to the resulting E407 (Carrageenan). After harvesting, E407 (Carrageenan) are generally processed into fully refined or semi-refined products. Fully refined products are processed either using an alcohol-precipitation method or a gel-press method. These refined methods produce the highest quality material with the least amount of odor, color and extraneous cellular material. Semi-refined products undergo a much less-intensive process and are simply alkali-extracted, bleached, dried and milled into a usable powder. Depending on the end application, it may be possible to use a more cost-effective semi-refined (formally referred to as PNG Philippine Natural Grade) as opposed to the more costly, but higher quality, fully refined E407 (Carrageenan).
Three main categories of E407 (Carrageenan) are typically used in the food industry today: kappa, iota and lambda. There are also combinations of kappa-iota and kappa-lambda type E407 (Carrageenan) frequently used for their complementary functionalities. Several common species include Chondrus crispus (mixture of kappa and lambda), Kappaphycus alvarezii (mainly kappa), Eucheuma denticulatum (mainly iota), Gigartina skottsbergii (mainly kappa, some iota), and Sarcothalia crispata (mixture of kappa and lambda). All E407 (Carrageenan) have a relatively simple molecular structure, made of a linear polymer of galactose sugars with intermittent sulfate substitutions, which identifies the type of E407 (Carrageenan).
From a structure-function perspective, the lower the amount of substitution on the galactose backbone, the higher the exhibited gel strength will be in the finished product. Kappa E407 (Carrageenan) has the lowest amount of sulfate substitution and therefore the highest gel strength and highest level of brittleness. Iota E407 (Carrageenan) have an intermediate level of substitution and therefore weaker overall gel strength, but they exhibit excellent flexibility and syneresis control. The third category of E407 (Carrageenan), lambda, is not utilized as a gelling agent, but instead provides viscosity and better mouthfeel. Lambda E407 (Carrageenan) have the highest level of substitution and therefore will not gel unless under the right conditions (e.g., the presence of milk proteins.) The addition of ions, such as potassium and calcium, can increase the gelling properties of kappa and iota E407 (Carrageenan), respectively.
E407 (Carrageenan) perform best when used in neutral environments, like milk systems, but specific types can tolerate more-acidic conditions, as long as milk proteins are not present in the system. Physical measurements generally used to quantify E407 (Carrageenan) performance include: ability to gel in milk, salt, and water systems; viscosity (water); milk reactivity; ash content; and mesh profile.
Dairy manufacturers have long used E407 (Carrageenan) for suspension and mouthfeel characteristics in beverages like chocolate milk, and dairy-alternative products such as soy milk. Formulations made with E407 (Carrageenan) will effectively maintain insoluble ingredients in suspensiondue to the formation of a gel networkwhile simultaneously improving mouth coating, a desirable sensory attribute. E407 (Carrageenan) help maintain freeze/thaw stability and proper eating characteristics in reduced-fat/ reduced-sugar ice cream. Manufacturers of pudding and gelled desserts depend on E407 (Carrageenan) to provide gelation, syneresis control and positive sensory attributes in their end applications. Meal-replacement and nutritional beverages benefit from the viscosity, quick hydrating and mouthfeel characteristics provided by E407 (Carrageenan).
The meat industry has found the gelling and water-holding capacity functionalities to be most beneficial for their products. E407 (Carrageenan), when used in combination with other emulsifying salts, can provide increased yields while also providing structural integrity to formed meat products. Meat-based pet food products also benefit from the use of E407 (Carrageenan) in retort canned products because of these same characteristics.
E407 (Carrageenan) have also been used in myriad other end applications, including baked goods, processed cheeses, pasteurized whole egg products, dairy-based salad dressings, gelatin-replacement applications, batters, confections and non-food applications, such as cosmetics, and pharmaceutical coatings.
The evolution of the use of E407 (Carrageenan) will continue to expand as food scientists find more creative ways to leverage its desirable functional attributes.
E407 (Carrageenan) are sulphated linear polysaccharides of d-galactose and 3,6-anhydro-d-galactose extracted from certain red seaweeds of the Rhodophyceae class. They have been extensively used in the food industry as thickening, gelling and protein-suspending agents, and more recently by the pharmaceutical industry as excipient in pills and tablets. Besides the well-known biological activities related to inflammatory and immune responses, E407 (Carrageenan) are potent inhibitors of herpes and HPV viruses and there are indications that these polysaccharides may offer some protection against HIV infection. Thus, this review describes important aspects of E407 (Carrageenan) related to their industrial/therapeutic applications, physicochemical properties and structural analysis. Moreover, chemical modifications of E407 (Carrageenan) that can lead to prototypes with potential application for the treatment of several diseases, such as herpes, HPV and AIDS, will be outlined.
E407 (Carrageenan) is obtained by extraction with water or alkaline water of certain species of the class Rhodophyceae (red seaweeds). It is a hydrocolloid consisting mainly of the potassium, sodium, magnesium, and calcium sulphate esters of galactose and 3.6-anhydrogalactose copolymers. The relative proportion of cations existing in E407 (Carrageenan) may be changed during processing to the extent that one may become predominant. E407 (Carrageenan) is recovered by alcohol precipitation, by drum drying, or by freezing. The alcohols used during recovery and purification are restricted to methanol, ethanol, and isopropanol. The commercial products classified as E407 (Carrageenan) are frequently diluted with sugars for standardization purposes and mixed with food grade salts required for obtaining gelling or thickening characteristics.
The most well-known and still most important red seaweed used for manufacturing E407 (Carrageenan) is Chondrus crispus, which grows along the coast of the Northern part of the Atlantic, the main harvesting areas being maritime provinces of Canada, Maine, Britanny in France, and the Iberian peninsula. Chondrus crispus is a dark red parsley-like plant which grows attached to the rocks at a depth of up to approx. 3 meters.
Most of the „moss“ is harvested by rakes from small boats. The rakes may be operated by hand only or drawn after a boat. The wet moss is brought to drying plants operated by the E407 (Carrageenan) manufacturers and dried to less than 20% humidity to preserve the quality of the seaweed and facilitate transportation to the extraction plant. Other red seaweeds are growing in importance as E407 (Carrageenan) raw materials, improving stability of supply and broadening the range of properties which can be achieved. Important species are Eucheuma cottonii, which yields kappa-E407 (Carrageenan), and Eucheuma spinosum which yields iota-E407 (Carrageenan). These Eucheuma species are harvested along the coasts of the Philippines and Indonesia. Long term stability of supply and price of E407 (Carrageenan) raw material will be ensured by seaweed farming. Seaweed farms are already operated on the Philippines, yielding sufficient Eucheuma cottonii of good and consistent quality to cover the present demand. Eucheuma spinosum, the raw material for iota-E407 (Carrageenan) has recently been farmed successfully.
E407 (Carrageenan) is extracted from the raw material with water at high temperatures. The liquid extract is purified by centrifugation and/or filtration. The liquid extract may be converted into a powder by simple evaporation of water to yield the so called drum dried E407 (Carrageenan). Proper release of the dried material from the dryer roll requires addition of a small amount of roll-stripping agents (mono- and diglycerides). The content of mono- and diglycerides is responsible for the drum dried E407 (Carrageenan) being turbid in watery solutions, and drum dried E407 (Carrageenan) consequently finds little use in water gel applications. Also, drum dried E407 (Carrageenan) contain all soluble salts present in the extract, which may influence the properties - for instance solubility of the E407 (Carrageenan). Most of the E407 (Carrageenan) used in foods is isolated from the liquid extract by selective precipitation of the E407 (Carrageenan) with isopropanol. This process gives a more pure and concentrated product.
E407 (Carrageenan) exhibits the solubility characteristics normally shown by hydrophilic colloids. It is water soluble and insoluble in most organic solvents. Water miscible alcohols and ketones, while themselves non-solvents for E407 (Carrageenan), are tolerated in admixture with E407 (Carrageenan) solutions at levels up to 40%. More highly polar solvents, such as formamide and N,N-dimethylformamide, are tolerated in still higher proportion and alone cause a marked swelling of the polymer.
The many forms of E407 (Carrageenan) possible through variation in structural detail, provide much variability in regard to solubility properties. For practical purposes, however, it is convenient to speak in terms of several general structural types and to equate solubility with the overall balance of hydrophilicity as provided by the hydrophilic sulphate and hydroxyl groups on one hand and the more hydrophobic 3.6-anhydro-D-galactose residues on the other. Thus, lambda E407 (Carrageenan), by definition void of 3.6-anhydro-D-galactose units and being highly sulphated is easily soluble under most conditions. Kappa E407 (Carrageenan) containing 3.6-anhydro-D-galactose as part of the repeating unit and fewer sulphate groups is less hydrophilic and less soluble. Intermediate is iota E407 (Carrageenan), more hydrophilic by virtue of its 2-sulphate which in addition to its position counteracts the less hydrophilic character of the 3.6-anhydro-D-galactose residue.
When dissolved by heating, followed by cooling below certain temperatures, kappa and iota E407 (Carrageenan) form thermoreversible water gels in a concentration as low as 0.5%, provided gelling cations are present. A gel has some properties of a solid and some of a liquid. Thus, it keeps its shape when tipped out of a container and yet retains the vapour pressure and conductivity of the liquid from which it is made. Kappa E407 (Carrageenan) gels in the presence of potassium ions, the rigidity of the gel increasing with increasing potassium ion concentration.
E407 (Carrageenan) will depolymerize slowly when stored. As the two most important properties of E407 (Carrageenan), gel strength and protein reactivity, are hardly dependent on degree of polymerization, the loss in strength over a period of one year at room temperature is undetectable. It is generally undesirable to blend a E407 (Carrageenan) powder with other powdered or crystalline ingredients of an acidic nature. However, when specific precautions are taken, it is possible to make stable blends of E407 (Carrageenan) and citric acid for exampel.
E407 (Carrageenan) is used in concentrations from as low as 0.005% to as high as 3.0% in a broad variety of products. Many types of E407 (Carrageenan) are made, some being standardized for general use as a gelling agent in water or milk systems and some being controlled by application tests, designed in coorporation between the user and the manufacturer. Standardization is done by blending different batches of E407 (Carrageenan) and/or by blending with an inert material such as sucrose or dextrose. Standardization of E407 (Carrageenan) with sugar is recognized in the EU stabilizer directive and the FAO/WHO-specification.
E407 (Carrageenan) is a thermoreversible gelling agent. Gel formation is obtained only in the presence of potassium ions (kappa and iota E407 (Carrageenan)) or calcium ions (iota E407 (Carrageenan)). When potassium ions are present, and the system is cooled below the gelling temperature, the E407 (Carrageenan) gels instantaneously. As no methods of releasing potassium slowly from slightly soluble salts or complexes are known today, potassium must be present in the system or added to the system before cooling below the gelling temperature in order to avoid pregelation. However, in certain applications for instance in the making up of solid bacteriological media, -gelation by diffusion of potassium ions may be used. E407 (Carrageenan) may be used in instant preparations (powders to be dissolved in cold water). However, only a thickening effect is obatined, caused by swelling of the E407 (Carrageenan). When the soluble solids content increases much above 50%, the gelling temperature of E407 (Carrageenan) is increased to a level that limits its use. High temperature, in combination with acid-pH normally applied in products with more than 50% soluble solids, causes rapid depolymerization of E407 (Carrageenan). In spite of the fact that E407 (Carrageenan) is a weaker gelling agent than agar, E407 (Carrageenan) finds extensive use as a gelling agent and stabilizing agent in the water phase of foods. This is mainly due to E407 (Carrageenan) ability to produce gels with a wide variety of textures. This is understandable when it is considered that E407 (Carrageenan) is not just a single polymer-type but rather family of gelling and non-gelling sulphated galactans. Combination with locust bean gum futher expands the texture range available. Iota E407 (Carrageenan) gels exhibit the unique property of freeze/thaw stability and thixotropy. The thixotropic nature of an iota E407 (Carrageenan) gel is essential when ready-to-eat water gels are filled at temperatures below the gelling temperature. Cold filling makes it possible to produce dessert gels topped with whipped cream or multilayer desserts and only an iota E407 (Carrageenan) gel will reform after mechanical destruction.
Permanent stabilization of a suspension requires the continuous liquid phase of the food to shows a yield value (a gel). Sedimentation rate decreases with decreasing difference in specific gravity and increasing viscosity (Stokes law). Increased viscosity will slow down the sedimentation but (unless the continuous phase possesses a yield value, i.e. is a weak gel, which traps the solid particles) the sedimentation rate will never be zero. E407 (Carrageenan) is used in low concentrations to stabilize suspensions and emulsions. When used in the proper low concentrations the gel structure of the E407 (Carrageenan) is not detectable when the suspension is poured and consumed. When the milk protein reactivity of E407 (Carrageenan) cannot be used (for instance in salad dressing and in soy protein based drinks) iota E407 (Carrageenan) is the preferred E407 (Carrageenan) as iota E407 (Carrageenan) produces thixotropic water gels. Apart from the stabilizing property, E407 (Carrageenan) may be used to increase viscosity and add mouthfeel to a liquid food product.
In milk products where gelation or structural viscosity is required, E407 (Carrageenan) is normally preferred of function and economic reasons. In gelled milk desserts kappa E407 (Carrageenan) is the most economical gelling agent to obtain a certain firmness, and is widely used in powder preparations for making flans. In ready-to-eat flan desserts the kappa E407 (Carrageenan) has insufficient water binding over the required shelf life of several weeks and „weaker“ kappa types, sometimes combined with iota types or LM-pectin, are used. When ready-to-eat milk dessert must be topped with whipped cream, cold (10EC) filling must be used. Only iota E407 (Carrageenan) can be used as it gives a thixotropic gel - a gel which reforms after mechanical destruction. Stabilization of cocoa particles and fat suspension in chocolate milk is obtained with as little as 0.02-0.03% kappa E407 (Carrageenan). Viscosity control and foam stability of instant breakfast preparations are obtained by incorporation of lambda E407 (Carrageenan). Ice cream stabilizers based on guar gum, locust bean gum and/or cellulose gum cause separation (whey off) of the ice cream mix. Low concentrations (0.01-0.02%) of kappa E407 (Carrageenan) forms a weak gel in the ice cream mix which prevents the separation.