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In the cell wall of agarophytes (red algae), Agar is a hydrophilic complex polysaccharide, which includes members of Gelidium and Gracilaria sp. It is a linear co-polymer L-galactopyranose with alternate associations of α (1→3) and β (1→4) units. Based on the purification process, residues of its parent porphyrane, D-galactose and L-galactopyranose6-sulfate may also be detected [37]. It is composed of two different fractions: agarose (neutral, gelling fraction, composed of galactose) and agaropectin (surface charged, non-gelling, composed of agarose, 3–10% (w/w) sulfate, varying amounts of ester sulfate, D-glucuronic acid, and pyruvic acid). The proportion of these fractions varies according to the seaweed [38]. Compared to other hydrocolloids, agar has excellent gelling and solubility characteristics. Due to repeating alternate sugars with α(1→3) and β(1→4) bonds, agar can form helical dimers similar to that of carrageenans. However, due to a comparatively lower content of anionic sulfates, agar forms nearly 2–10 times stronger gels with a melting point close to the boiling point of water [39].