Agar agar is a hydrocolloid biosynthesized in the cell walls of red seaweeds (Gracilaria, Gelidium and Pterocladia species), composed by a complex mixture of homogeneous polysaccharides: Agarose and Agaropectin.
Agarose, is a strongly gelling, non-ionic polysaccharide which is regarded as consisting of 1,3- linked β-D-galactopyranose and 1,4-linked 3,6-anhydro-α-L-galattopyranose units.
Agaropectin, is a less clearly defined, more complex polysaccharide having sulfate groups attached to it, that strongly influence solution properties, gelling kinetics and gel features.
Agar agar is a well accepted and label friendly natural additive used as a gelling agent, thickener, texturizer, moisturizer, emulsifier, flavor enhancer and absorbent in the food industry and in a growing number of cosmetic, pharmaceutical and technical applications.
Agar agar can serve also as a natural source of vegetable origin dietary fiber and as an intestinal regulator. Once ingested, the powder hydrates and absorbs a large amount of water. This results in the consumer feeling fuller.
Agar agar may also be used as the gelling agent in gel clarification, a culinary technique used to clarify beer and other liquids.
Refined agar is usually used as the solid or semi-solid culture medium of microorganisms analysis.
The agarose fraction extracted from agar is also extensively applied in clinical assay, biochemical analysis and purification of high weight biological molecules like DNA.
- Agar agar is a versatile hydrocolloid completely soluble in boiling water.
- Special Agar agar powders can be dissolved at lower temperatures.
- Agar provides odourless, colourless superior quality gels even at very low concentrations.
- It has good synergies with sugars and with different hydrocolloids.
- Agar is the strongest natural jelling agent and provides a thermo reversible gel.
- Agar solutions gel at temperatures from 35 °C to 43 °C and melt at temperatures from 85 °C to 95 °C.
- Agar agar is the only hydrocolloid that gives gels that can stand sterilization temperatures and has an excellent resistance to enzymatic hydrolysis
- Agar agar does not require addition of other products or ions for gelatinization
- Agar reacts only with water which allows its incorporation in most of the food formulations
- Agar is perfectly compatible with proteins, for example in dairy application