Abstract: Substantially dry, rehydratable, water-dispersible, gel-forming, porous hydrocolloid micro-particulates containing internally or internally and externally at least one water-soluble, non-gelling, hydration enhancing hydrocolloid, processes and intermediates for their preparation, and their uses.

Abstract: Irradiated or nonirradiated substantially pure .beta.-1,3-glucan polysaccharides, derivatives and coprocessed mixtures thereof with other hydrocolloids, methods for their preparation, and uses for the aqueous gels prepared from them, including their use in the electrophoresis of DNA, RNA, and their fragments.

Abstract: Substantially dry, rehydratable, water-dispersible, gel-forming, porous hydrocolloid microparticulates containing internally or internally and externally at least one water-soluble, non-gelling, hydration enhancing hydrocolloid, processes and intermediates for their preparation, and their uses.

Abstract: Purified and substantially pure &bgr;-carrageenan and processes for their preparation. Purified &bgr;-carrageenan can be obtained from a marine macroalga containing &bgr;-carrageenan and/or a precursor thereof by the steps of: A. where the macroalga contains a precursor of &bgr;-carrageenan, reacting the macroalga with an alkaline compound to convert the precursor to &bgr;-carrageenan, B. extracting carrageenan from the macroalga, C. treating the extracted carrageenan with an aqueous quaternary ammonium salt to form a precipitate and an aqueous solution, D. separating the solution from the precipitate, and E. isolating purified &bgr;-carrageenan from the solution. Substantially pure &bgr;-carrageenan can be obtained from purified &bgr;-carrageenan by the further steps of: F. forming a solution of purified &bgr;-carrageenan in water, G. contacting the solution with an ion exchange agent that removes carrageenan which contains sulfate ester from the solution, H.