21 CFR § 172.620 - Carrageenan.
(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.
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