Agar

CAS: 9002-18-0

Ref. 3D-OA39737

Product Information

• Name: Agar
• Brand: Biosynth
• Description: The major gel forming component in agar, agarose, consists of a linear chain of sequences of 1,3 linked β-D-galactopyranosyl units and 1,4 linkages to 3,6-anhydro-α-L-galactopyranosyl units. Gelation is done via the formation of double helices (Arnott, 1974). Agar's properties are similar to gelatin as it is primarily used as a plating gel for microbial cultures (Lahaye, 1991). However, agar is a good substitute for animal-based gelatin in vegetarian foods and is easy to use in food gels in a similar way to the carrageenans. Common food applications of agar include: puddings, custards, and soft candies. Agar improves the texture of processed cheese and frozen desserts, and is also added to baked goods to inhibit staling. A creative food application uses agar-based gel cubes that are infused with fruit extract or wine to make a vegetable-based aspic (Armisén, 2009).Agar contains two polysaccharides Agarobiose and Agaropectin. Both Gelidium latifolium and Gelidium amansii are sources of both Agar and Agarose. The images were kindly provided by Prof Mike Guiry from Cork who runs ‘The Seaweed Site’.AgaropectinAgaropectin is a sulphated non-gelling galactan comprising about 30% of Agar. Half ester sulphate is present in varying amounts plus D-glucuronic acid and small amounts of pyruvic acid. As with Agarose the main chain has alternating residues of D-galactose and L-galactose heavily modified with acidic side-groups which are usually sulfate, glucuronate, and pyruvate. Pyruvic acid is possibly attached in an acetal form to the D-galactose residues of the agarobiose skeleton. No formal structure of Agaropectin appears to have been published.AgaroseAgarose is a linear gelling polysaccharide of (1-3) linked β-D-galactopyranose residues linked to 3,6-anhydro-α-L-galactopyranose via 1-4 bonds. Agar contains about 60% Agarose.

Chemical properties

• Purity: Min. 95%
• Color/Form: Powder