Semi-refined carrageenan

DETAILED DESCRIPTION The present invention provides methods for preparing a carrageenan product comprising the steps of providing a carrageenan-containing seaweed material having a seaweed solids content of less than 25% by weight, and subjecting this seaweed material to shear stress treatment.
The carrageenan-containing seaweed material optionally is treated with base prior to extrusion.
In one embodiment, the carrageenan-containing seaweed material is prepared by a process comprising the steps of washing the seaweed with water to produce washed seaweed; rinsing the seaweed with water to form rinsed seaweed; and washing the rinsed seaweed with water or an aqueous solution to form the carrageenan-containing seaweed material.
In another embodiment, the methods of the present invention comprise washing the seaweed with water; treating the seaweed with a base at a temperature of about 25° C.
to about 65° C.
to form base-modified seaweed; rinsing the base-modified seaweed with water; washing this base-modified seaweed with an aqueous solution of a salt; rinsing this base-modified seaweed with water to form processed seaweed, wherein the processed seaweed comprises less than 25% solids; extruding this processed seaweed to form extruded seaweed; and drying the extruded seaweed to form a carrageenan product.
In yet another embodiment, the concentration of the aqueous salt solution is less than about 40%.
It is preferred that the concentration of the aqueous salt solution be less than about 15%.
It is more preferred that the concentration of the aqueous salt solution be between about 2% and about 15%.
The present invention also includes carrageenan products that preferably comprise at least about 60% by weight of carrageenan and at least about 2% by weight of acid insoluble material, and have an onset of hydration below about 50° C.
In a preferred embodiment, the carrageenan product is derived from Eucheuma spinosum, or any other species containing iota-carrageenan.
In another preferred embodiment, the carrageenan product further comprises about 2% to about 15% by weight of a salt