Agar

Thickening agent used in microbiology and food

Agar ( or), or agar-agar, is a jelly-like substance consisting of polysaccharides obtained from the cell walls of some species of red algae (phylum Rhodophyta) primarily from the Gracilaria genus (Irish moss, ogonori) and the Gelidiaceae family (tengusa). These algae are known as agarophytes. As found in nature, agar is a mixture of two components, the linear polysaccharide agarose and a heterogeneous mixture of smaller molecules called agaropectin.

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