Abstract: An improved process for the manufacture of gelling carrageenans from seaweed, wherein the seaweed is subjected to a heterogenous reaction for alkali modification of at least one carrageenan precursor to at least one gelling carrageenan followed by a recovery process. In the recovery process one or more lye recovery sections for the recovery of aqueous alkaline medium are used and there is reusing in the heterogeneous reaction of used aqueous alkaline medium after processing of incoming seaweed and for each recovery section there is reusing of at least part of the used lye recovery solution to compensate for the deficiency of alkaline medium as a result of the heterogeneous reaction.

Abstract: An improved process for the manufacture of gelling carrageenans from seaweed, wherein seaweed is subjected to a heterogenous reaction for alkali modification of the carrageenan precursor(s) to the gelling carrageenan(s) followed by a recovery process comprising one or more lye recovery sections for the recovery of aqueous alkaline medium, a washing process comprising one or more washing sections and further conventional work-up, provides for substantially savings in the amount of alkaline aqueous medium spent in the process.

Abstract: A method for the manufacture of carrageenans from bi-component seaweed material, wherein the seaweed is subjected to 1) a heterogeneous reaction step in an aqueous alkaline medium having specific values of alkali concentration, temperature and salt concentration; 2) separation of the solid material from the liquid phase; 3) fractionation of the lambda-family carrageenans from the solid material obtained in 2) by treatment with an aqueous medium; and 4) optionally further purification steps, provides for efficient production and separation of kappa-family carrageenans and lambda-family carrageenans respectively.

Abstract: An improved method for the manufacture of gelling carrageenens from seaweed, wherein mono-component seaweed is subjected to a heterogeneous reaction step, one or more washing step (s), and further workup provides for substantial savings in alkali costs as non-expensive alkalis, such as NaOH, Na2CO3,Na-phosphates, K2CO3, K-phosphates, ammonia may be used in the heterogeneous reaction step.