Keywords: eucheuma cottonii, carrageenan, precipitation.
Distantina Sperisa, Fadilah, YC. Danarto, Wiratni, dan Moh. Fahrurrozi*)
LPPM UNS, Penelitian, DP2M, Hibah Pekerti, 2009
Carrageenan represent one of the major texturising ingredients in the food industry. Chemical used in seaweed processing effects on yield and gelling properties of carrageenan from Eucheuma cottonii seaweed, largely sourced from Indonesia. The properties differ from batch to batch. Therefore, the quantitative analysis of carrageenan batches is important. The effects of chemical in precipitation on yield and gelling properties were investigated in this research. The carrageenan was prepared by alkaline extraction, followed by alcohol or KCl precipitation. In preparing carrageenan, seaweeds, Eucheuma cottonii, were extracted using aqueous sodium hydroxide or potassium hydroxide as the solvent at concentration 0.2N. The ratio solvent volume-seaweed weight was set 750/25 mL/g. The solvent was taken in an erlenmeyer which placed in a water bath maintained at boiling temperature. The required quantity of the seaweeds were added to the solvent. Agitation was conducted sometimes by hand. The constant solvent volume is maintained by adding hot distilled water some times. After extraction, the carrageenan were recovered by precipitation with adding various concentration of ethanol ( 70 – 90%) or KCL (0,1 -3,5% w), various filtrate – coagulant volume ratio (1:1 – 1:3), and then dried until constant weight. Based on the evaluation of experimental data, it was found that better carrageenan properties (gel strength, melting and gelling temperature) and higher yield were obtained by using KCl at higher concentration.