21 CFR § 172.620 - Carrageenan.
The food additive carrageenan may be safely used in food in accordance with the following prescribed conditions:
(a) The food additive is the refined hydrocolloid prepared by aqueous extraction from the following members of the families Gigartinaceae and Solieriaceae of the class Rodophyceae (red seaweed):
(b) The food additive conforms to the following conditions:
(1) It is a sulfated polysaccharide the dominant hexose units of which are galactose and anhydrogalactose.
(2) Range of sulfate content: 20 percent to 40 percent on a dry-weight basis.
(c) The food additive is used or intended for use in the amount necessary for an emulsifier, stabilizer, or thickener in foods, except for those standardized foods that do not provide for such use.
(d) To assure safe use of the additive, the label and labeling of the additive shall bear the name of the additive, carrageenan.