Carrageenan is a naturally-occurring family of carbohydrates extracted from red seaweed.. Carrageenan is extracted with water under neutral or alkaline conditions at elevated temperature. Refined carrageenan is mainly recovered from solution by alcohol precipitation or potassium gelation.
Semi-refined carrageenan is washed and alkali treated seaweed. The carrageenan is not extracted out of the seaweed but is still contained in the cell wall matrix. Commercial carrageenan products are frequently standardized for obtaining optimal gelling and thickening properties. By using the appropriate carrageenan product, the formulator can create textures ranging from free-flowing liquids to solid gels.
Carrageenans are large, highly flexible molecules that curl forming helical structures. This gives them the ability to form a variety of different gels at room temperature. They are widely used in the food and other industries as thickening and stabilizing agents. A particular advantage is that they are pseudoplastic—they thin under shear stress and recover their viscosity once the stress is removed. This means that they are easy to pump, but stiffen again afterward.
