Powder characteristics and Storage Stability

Carrageenan is sold as a powder. The color ranges from white to brownish depending on raw material and process used. A typical mesh specification is

99% through a 60 mesh (0.25 mm) sieve.

A typical powder density of an alcohol precipitated carrageenan is 0.7.
A typical equilibrium water content of an alcohol precipitated carrageenan is

15% at 50% r.h. 25% at 70% r.h.

Carrageenan is insoluble in organic solvents such as alcohol, ether, and oil.

Solubility in water depends on the structure of the particular carrageenan, the medium, and the temperature. Generally the gelling carrageenans must be heated to dissolve whereas non-gelling carrageenans may be dissolved in cold water.

Stability

Carrageenan will depolymerize slowly when stored. As the two most important properties of carrageenan, gel strength and protein reactivity, are hardly dependent on degree of polymerization, the loss in strength over a period of one year at room temperature is undetectable.

It is generally undesirable to blend a carrageenan powder with other powdered or crystalline ingredients of an acidic nature. However, when specific precautions are taken, it is possible to make stable blends of carrageenan and citric acid for example.

Standardization

Carrageenan is used in concentrations from as low as 0.005% to as high as 3.0% in a broad variety of products. Many types of carrageenan are made, some being standardized for general use as a gelling agent in water or milk systems and some being controlled by application tests, designed in cooperation between the user and the manufacturer.

Standardization is done by blending different batches of carrageenan and/or by blending with an inert material such as sucrose or dextrose.

Standardization of carrageenan with sugar is recognized in the EU stabilizer directive and the FAO/WHO-specification.

Quality Control

Carrageenan has a high (natural) ash content, originating from the sulfate half ester groups and the cations. On ashing, some of the sulfate evaporates as SO3, and the ash content is accordingly found to be lower than expected from SO4 and cation content.

Purity specifications for carrageenan can be requested from any of our sales offices worldwide.