Production of semi-refined carrageenan from locally available red seaweed, Eucheuma cottonii on a laboratory scale

摘要

Procedures for ihe production of semi-retmed carrageenan (SRC) from local red seaweed. Eucheuma cottunii involved pre-treatment. alkali extracdon. neutralisation. drying and grinding. The optimal conditions for pre-treatment involved washing the driedseaweed under running water for 2 minutes. For alkaline extracdon. the optimum conditions were extracdon using potassium hydroxide at pH 13 for 1 hour at lemperature of 80 °C followed by neutralisation whereby the SRC was soaked in water (1:3) for 4 hours followed by second soaking overnight. Drying can be carried out using a choice of threc optimal conditions namely drying at 70 °C for 5 hours, 60 °C tbr 8 hours or 50 °C for 24 hours. The SRC produced had physical and chemical properties comparable to the purity specifications of the EEC Council Directive (78/663/EEC)(1978) that is specifications for pure carrageenan.