Gelidium

genus of red algae

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Last updated

July 21, 2026

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The genus Gelidium refers to a type of red algae, belonging to the division Rhodophyta. These algae are significant sources of agar, a gelatin-like substance primarily extracted from Gelidium and Gracilaria species. Agar is widely used as a solidifying agent in bacteriological culture media and as a gelling and stabilizing agent in various food products, including ice cream and pastries. It also finds applications in cosmetics, medicines, and dentistry. The algae themselves have a gelatinous texture and can retain their color when cooked.1234

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agar
…primarily from the red algae Gelidium and Gracilaria (division Rhodophyta). Best known as a solidifying component of bacteriological culture media, it is also used in canning meat, fish, and poultry; in cosmetics, medicines, and dentistry; as a clarifying agent in brewing and wine making; as a thickening agent in ice…
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…primarily from the red algae Gelidium and Gracilaria (division Rhodophyta). Best known as a solidifying component of bacteriological culture media, it is also used in canning meat, fish, and poultry; in cosmetics, medicines, and dentistry; as a clarifying agent in brewing and wine making; as a thickening agent in ice…
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