All carrageenans are high-molecular-weight polysaccharides made up of repeating galactose units and 3,6 anhydrogalactose (3,6-AG), both sulfated and nonsulfated. The units are joined by alternating α-1,3 and β-1,4 糖苷键。
- 阿欧塔型（ι，Iota） - 柔软、富有弹性的凝胶，从麒麟菜属植物的Eucheuma denticulatum或异枝麒麟菜（Eucheuma spinosum）中提取。
- 卡帕型（κ，Kappa）- 當鉀離子的存在時，可與奶製品形成硬的、具刚性的凝胶。主要从卡帕藻屬的Kappaphycus alvarezii或耳突卡帕藻（Kappaphycus cottonii）中提取。
- 拉姆达型（λ，Lamda）- 当与蛋白质而不是水混合时，形成凝胶, 用作奶制品的增稠剂。来自南欧的杉藻属（Gigartina ）植物是最主要的来源。
- Fruit Gushers: ingredient in the encapsulated gel
- Marbling: the ancient art of paper and fabric marbling uses a carrageenan mixture on which to float paints or inks; the paper or fabric is then laid on it, absorbing the colours
- Pharmaceuticals: used as an inactive 賦形劑 in pills and tablets
- Diet sodas: to enhance texture and suspend flavours
- Vegetarian hot dogs
In the U.S., carrageenan is allowed under FDA regulations as a direct food additive and is considered 公认安全 when used in the amount necessary as an emulsifier, stabilizer, or thickener in foods, except those standardized foods that do not provide for such use. FDA also reviewed carrageenan safety for infant formula. The European Food Safety Authority concluded "there is no evidence of any adverse effects in humans from exposure to food-grade carrageenan, or that exposure to degraded carrageenan from use of food-grade carrageenan is occurring", Furthermore, the Joint FAO/WHO expert committee on food additives stated in a July 2014 review of carrageenan "that the use of carrageenan in infant formula or formula for special medical purposes at concentrations up to 1000 mg/L is not of concern".
Although the National Organic Program (NOP) had added carrageenan to its National List of additives allowed to be included in organic foods in 2003, and reviewed and reauthorized it in 2008, noting it as "critical to organic production and handling operations", on November 18, 2016 the NOP's National Organic Standards Board (NOSB) voted to recommend carrageenan be removed from the National List of additives allowed in organic food production.
On April 4, 2018 the Agricultural Marketing Service (AMS) (美国农业部) published a document to announce the renewal of carrageenan on the National List, allowing its continued use in food products. The document states, “The NOSB recommended removing carrageenan because they determined that alternative materials, such as gellan gum, guar gum, or xanthan gum, are available for use in organic products” continuing, “AMS found sufficient evidence in public comments to the NOSB that carrageenan continues to be necessary for handling agricultural products because of the unavailability of wholly natural substitutes (§ 6517(c)(1)(ii)). Carrageenan has specific uses in an array of agricultural products, and public comments reported that potential substitutes do not adequately replicate the functions of carrageenan across the broad scope of use. Therefore, carrageenan continues to meet the OFPA criteria for inclusion on the National List.”  The rule went into effect May 29, 2018.
In the most recent review by an independent panel, the Joint Expert Committee of the 联合国粮食及农业组织 of the 联合国 and 世界卫生组织 on Food Additives released a technical report in 2015 on the use of carrageenan in 配方奶粉 and found that the additive was ‘not of concern’ in infant formula as food for special medical purposes at concentrations up to 1000 千克s per 公升. 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.
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”.
Degraded carrageenan (poligeenan) has been found to cause inflammation of the gut, altering microbiota, and was found to be a triggering factor of inflammatory bowel diseases such as ulcerative colitis and Crohn Disease.
Food-grade carrageenan has been confused with poligeenan, although they are completely different products, creating a controversy over the food-additive's safety. Food-grade carrageenan's safety has been proven through various studies.
- FAO Agar and Carrageenan Manual. Fao.org. 1965-01-01 [2011-12-10] （英语）.
- McHugh, Dennis J. A guide to the seaweed industry: FAO Fisheries Technical Paper 441. www.fao.org. Food and Agriculture Organization, United Nations. 2003 [2017-07-29] （英语）.
- 21 Code of Federal Regulations 172.620
- Generally Recognized As Safe 21 CRF §182.7255 GRAS ID Code 9000-07-1 (1973)
- Federal Food, Drug, and Cosmetic Act 21 U.S.C. 350(a) §412
- Opinion of the Scientific Committee on Food on Carrageenan (2003)  p. 5
- Joint FAO/WHO Expert Committee on Food Additives. Who.int. Retrieved on 2014-8-11.
- 68 FR 61993 (2003)
- 65 FR 80548
- 73 FR 59481
- Sunset 2018 Review Summary NOSB Final Review (PDF). USDA Agricultural Marketing Service. 2016-11-30 [2017-02-15].
- 83 FR 14347. USDA Agricultural Marketing Service. 2018-04-04 [2018-04-21].
- Safety Evaluation of Certain Food Additives, 3. Joint Expert Committee on Food Additives, WHO Food Additive Series: 70. 2015. ISBN 9789241660709. hdl:10665/171781.
- Opinion of the Scientific Committee on Food on Carrageenan (PDF). European Commission, Scientific Committee on Food. 2003.
- Tees Ltd recalls Sweetworld Yummys Jelly Cones because of a choking hazard.
- Martino, John Vincent; Van Limbergen, Johan; Cahill, Leah E. The Role of Carrageenan and Carboxymethylcellulose in the Development of Intestinal Inflammation. Frontiers in Pediatrics. 1 May 2017, 5: 96. PMC 5410598. PMID 28507982. doi:10.3389/fped.2017.00096.
- Shang, Qingsen; Sun, Weixia; Shan, Xindi; Jiang, Hao; Cai, Chao; Hao, Jiejie; Li, Guoyun; Yu, Guangli. Carrageenan-induced colitis is associated with decreased population of anti-inflammatory bacterium, Akkermansia muciniphila , in the gut microbiota of C57BL/6J mice. Toxicology Letters. September 2017, 279: 87–95. PMID 28778519. doi:10.1016/j.toxlet.2017.07.904.
- Moyana, TN; Lalonde, JM. Carrageenan-induced intestinal injury in the rat--a model for inflammatory bowel disease.. Annals of Clinical and Laboratory Science. 1990, 20 (6): 420–6. PMID 2073092.
- McKim JM. 2014. “Food additive carrageenan: Part I: A critical review of carrageenan in vitro studies, potential pitfalls, and implications for human health and safety
- Weiner ML. 2014. “Food additive carrageenan: Part II: A critical review of carrageenan in vivo safety studies.
- McHugh, Dennis J. FAO Fisheries Technical Paper 288 - Production and Utilization of Products from Commercial Seaweeds, Chapter 3 - Production, Properties and Uses of Carrageenan, 联合国粮食及农业组织, Rome, 1987
- Guiry, Michael D.R. Carrageenans, The Seaweed Site: information on marine algae.