Extraction of carrageenan from Eucheuma spinosum using ohmic heating: optimization of extraction conditions using response surface methodology

Seaweed is an important global commodity since it the source of many products such as carrageenans, agar, alginates, and bioactive compounds. processing energy intensive process involves heating large volumes seaweeds in alkali solutions at high temperatures for up to six hours. To increase efficiency, ohmic based system has been developed but not tested thoroughly. Therefore, objective this study was identify optimum conditions extraction carrageenan from Eucheuma spinosum using technology. The experiment conducted Central Composite Design with four variables, i.e. temperature, duration, KOH concentration, solution seaweed ratio. Following process, recovered through precipitation 90% isoprophyl alcohol solution. Results experiments indicate that yields varied 29.6-62.4% dry basis viscosity gel strength 259-290 mPa.s 42.54-70.41 g/cm2 respectively. Statistical analysis indicated yield can be adequately modeled variables (61.59%), (53.48 g/cm2), (284.51 mPa.s) were achieved 95 °C 240 minutes time, 0.4M 45:1