Campo VL, Kawano DF, da Silva DB, Carvalho I (2009) Carrageenans: biological properties, chemical modifications and structural analysis - a review. Carbohydr Polym 77:167–180

Souza RB, Frota AF, Silva J, Alves C, Neugebauer AZ, Pinteus S, Rodrigues JAG, Cordeiro EMS, de Almeida RR, Pedrosa R, Benevides NMB (2018) In vitro activities of kappa-carrageenan isolated from red marine alga Hypnea musciformis: antimicrobial, anticancer and neuroprotective potential. Int J Biol Macromol 112:1248–1256 Carrageenan has established itself as a polysaccharide with numerous applications ranging from food to pharmaceuticals. Carrageenan is primarily derived from the red algae K. alvarezii, which is the commercial variety of choice due to its rapid growth and low production cost in tropical coastal waters around the world. Carrageenan is synthesized through a series of complex biochemical pathways primarily catalyzed by sulfotransferases and galactosyltransferases and their derivate enzymes. Carrageenan’s chemical and rheological properties are altered by the addition of sulfate ester groups and anhydrogalactose, which alters its gelling and viscosity properties. Because of its desirable gelling properties, κ-carrageenan is particularly useful for industrial purposes. Carrageenan can be extracted using strong alkalies or through enzymatic hydrolysis with cellulases; however, the latter method is not currently commercially viable in an industrial setting. The production of Kappaphycus seaweeds is influenced by both biotic and abiotic factors, and the emergence of new pathogens is cause for concern, emphasizing the importance of disease-tolerant strain selection. Global warming and climate change have been shown to have a direct effect on ocean acidity, while eutrophication caused by terrestrial runoff has also been shown to have a direct effect on productivity. Aside from carrageenan, research is becoming increasingly important for identifying clinically important biomolecules as potential substitutes for current pharmaceutical drugs. The emergence of the oceans as the next frontier in agriculture will ensure that carragenophytes remain on the scientific horizon as an economically and environmentally viable option for humanity’s future. Author ContributionsThe three essential steps of carrageenan extraction using the UAE method are algae pretreatment, carrageenan extraction, and carrageenan purification ( Youssouf et al., 2017). The pretreatment process was started by incubating dried seaweed ( K. alvarezii) in an 80% ethanol solution at room temperature overnight. The pre-treated seaweed was then filtered before being subjected to an ultrasound at 150W for 15min to extract the carrageenan. The movement of ultrasonic waves mediates the extraction process, which results in the transformation of ultrasonic waves into mechanical energy. This mechanical energy then ruptures the cell wall, reducing particle size as a result of the rupture and releasing the carrageenan from the cell wall ( Nigam et al., 2022). Following the extraction process, the carrageenan was available in the form of a solution, and any remaining algal residues were removed using a hot filtering process. It was necessary to place the filter at 4°C for several hours to obtain carrageenan extract in the form of a gel, and gel carrageenan was frozen and lyophilized to obtain the final carrageenan powder ( Youssouf et al., 2017). Ultrasounds allowed for the extraction of 50–55% of carrageenans from red seaweeds such as K. alvarezii and E. denticulatum in 15min, and a longer ultrasonic treatment (30min) may not result in a higher extraction yield ( Youssouf et al., 2017; Azis, 2019). Factors Affecting Carrageenan Yield and Production MAH forms maleic acid and esters when dissolved in water and ethanol, respectively, thus creating a mixture in the reaction [ 23]. Previous studies mostly focused on the reaction of MAH with starch and rarely on the reaction of MAH with κCar. Zuo et al. [ 10] reported that MAH modification for starch occurs mainly in the amorphous region of the granule with the maximum degree of substitution (DS) of 0.3386. The availability of -OH groups at C-2, C-3, and C-6 (glucose unit, Mw 162) renders native starch reactive for substitution [ 24]. κCar consists of alternating (1→3)-β- d-galactose-4-sulfate and (1→4)-3,6-anhydro-α- d-galactose residues joined in a linear chain, in which the available -OH groups possess different reactivities for esterification [ 1]. Similar to starch, κCar has an extremely high water-absorbing capacity to react easily. However, κCar has no crystalline region, which means that the water-absorbing capacity of κCar is higher than that of starch. Therefore, κCar has less reactivity than starch, leading to a lower DS. Gel strength is also an important index for κCar. High gel strength is not always the most desirable quality for κCar. However, low strength bestows the product with a stable structure and soft elastic characteristics. κCar with low gel strength has potential uses in liquid food, spread food, soft-texture confectionery, fat replacers, and new industrial applications, and can also serve as a cryoprotectant to minimize the damage of freezing–thawing [ 25, 26]. Thus, the effects of five factors on the DS and gel strength of MC were studied. Many red algal species produce different types of carrageenans during their developmental history. For instance, the genus Gigartina produces mainly kappa carrageenans during its gametophytic stage, and lambda carrageenans during its sporophytic stage. All are soluble in hot water, but in cold water, only the lambda form (and the sodium salts of the other two) are soluble. Azis A. (2019). Optimization of temperature and time in carrageenan extraction of seaweed ( Kappaphycus alvarezii) using ultrasonic wave extraction methods. IOP Conf. Series Earth Environ. Sci. 370:012076. doi: 10.1088/1755-1315/370/1/012076 [ CrossRef] [ Google Scholar]

The essential difference in the refining process is that the carrageenan is first dissolved and filtered to remove cell wall debris. The carrageenan is then precipitated from the clear solution, either by isopropyl alcohol (propan-2-ol) or by potassium chloride. [18] Mixed processing [ edit ] Healthline has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references. You can learn more about how we ensure our content is accurate and current by reading our editorial policy. David, Shlomit; Shani Levi, Carmit; Fahoum, Lulu; Ungar, Yael; Meyron-Holtz, Esther G.; Shpigelman, Avi; Lesmes, Uri (2018-03-01). "Revisiting the carrageenan controversy: Do we really understand the digestive fate and safety of carrageenan in our foods?". Food & Function. 9 (3): 1344–1352. doi: 10.1039/c7fo01721a. ISSN 2042-6496. PMID 29469913.

Carrageenan Structure and Physicochemical Properties

Ohno M, Nang HQ, Hirase S (1996) Cultivation and carrageenan yield and quality of Kappaphycus alvarezii in the waters of Vietnam. J Appl Phycol 8:431–437 A kappa-iota hybrid carrageenan provides advantages of both types with high gel strength and water-binding with low syneresis. Applications in the food industry and regulatory status

Liberman, P. (2012). Allergicreaction to ice cream containing kernel oil, locust bean, and carrageenan:Availability of serum-specific ige testing to these potential allergens.Retrieved from Sunset 2018 Review Summary NOSB Final Review" (PDF). USDA Agricultural Marketing Service. 2016-11-30 . Retrieved 2017-02-15. While valid, these concerns are primarily based on a form called poligeenan, which, unfortunately, early studies did not distinguish between carrageenan and degraded carrageenan – or poligeenan. 4 Poligeenan is not approved for use as a food additive.Variations in transparency occur due to the penetration, refraction, and reflection of light at different intensities when irradiating different solutions. Transparency affects product quality, properties, and uses. Carrageenan with high transparency is widely used. Highly transparent carrageenan film for observational experiments can be prepared by mixing with glycerol. As shown in Table 1, the transparency of MC increased remarkably from 81.9% to 91.6% by 11.8% with the increase in DS. The results could be explained as follows: the introduction of MAH groups prevented the carrageenan molecules from binding to each other and the formation of the double helix structure, thus allowing light to penetrate easily [ 37]. The gelling and gel melting temperature of κCar were measured at shear deformation by using the TA instrument TRIOS rheometer and the modified method of Derkach et al. [ 54]. Temperature scanning was performed from 20 °C to 80 °C, followed by 80 °C to 20 °C at a scan rate of 2 °C/min, an amplitude of deformation γ = 1%, and a frequency ω = 6.28 c −1. The diameter of the cone was 40 mm, the angle between the cone and plate was 1 grad, and the gap between the cone top and the plate was 0.1 mm. Craigie JS, Leigh C (1978) Carrageenans and agars. In: Hellebust JA, Craigie JS (eds) Handbook of phycological methods. Cambrige University Press, Cambrige, pp 109–131 In a 2015 review, the Joint Expert Committee of the Food and Agriculture Organization of the United Nations and World Health Organization on Food Additives released a technical report in 2015 on the use of carrageenan in infant formula and found that the additive was "not of concern" in infant formula as food for special medical purposes at concentrations up to 1000 milligrams per litre. [29] The use of carrageenan in infant formula, organic or otherwise, is prohibited in the EU for precautionary reasons, but is permitted in other food items. [30] In 2018, the European Food Safety Authority (EFSA) reported that safety of carrageenan in food products is based on an ADI of 75mg/kg body weight per day. [4]

K. A. Pittman, L. Golberg and F. Coulston, Carrageenan: the effect of molecular weight and polymer type on its uptake, degradation and excretion in animals, Food Chem. Toxicol., 1976, 14, 85–93 CrossRef CAS. Kappa . In the presence of calcium, kappa carrageenan forms a stiff and brittle gel, but in the presence of potassium salts, it forms firm and elastic gels. Search more than 32,000 food, beverage and nutrition ingredients on UL Prospector! Find the ingredients you need today!The most commonly used sources are Eucheuma cottonii, Kappaphycus alvarezii, and Eucheuma spinosum, which together provide about three-quarters of the world production. [ citation needed] These grow from the sea surface to a depth of about 2m (6.6ft). The seaweed is normally grown on nylon lines strung between bamboo floats, and it is harvested after three months or so, when each plant weighs approximately 1kg (2.2lb). Viñas M., Souto S., Flórez-Fernández N., Torres M. D., Bandín I., Domínguez H. (2021). Antiviral activity of carrageenans and processing implications. Mar. Drugs 19:437. doi: 10.3390/md19080437, PMID: [ PMC free article] [ PubMed] [ CrossRef] [ Google Scholar] In the UK, the Food Standards Agency issued a product recall for sweets containing carrageenan, stating that carrageenan "is not permitted as an ingredient in jelly confectionery products as it presents a choking hazard". [31] Toxicity research [ edit ] Values are mean ± standard deviation. Different lowercase superscripts within the same column indicate significant differences ( p< 0.05). Our Carrageenan Kappa is a premium quality powder of European origin. It can be used to make firm elastic gels that are freeze/thaw stable. An ideal Vegan alternative to Gelatine. It releases maximum flavour, makes crystal clear gels and glazes, which are perfect for topping mousses, cakes and flans and works at room temperature. Due to the strength of the gel it is ideal for encasing liquid centres. Carrageenan Kappa gel strengthens in the presence of Calcium, making it perfect for use in milk and dairy-based recipes. Its many uses include adding a dilution of Kappa to yoghurt or cheese to prevent separation. Soluble in hot water. Suitable for Vegans, Vegetarians & Ovo- Lacto Vegetarians, Non-GMO, Gluten-free, Non-Irradiated