Abstract: Oil-absorbing property of kelpLaminariajaponicaresidues extruded and modified by stearic acid were studied to evaluate effects of kelp residues particle size and addition amount of corn flour and modification time on oil-absorbing property. Results showed that the expansion degree, oil absorption rate and floating rate were significantly increased with increase in mass ratio of corn flour, with elevated water absorption rate. Also, higher oil absorption rate and floating rate and much lower water absorption rate were observed in the extruded kelp residues with smaller particle size. The oil absorption rate of 142.8%, ratio of oil absorption rate to saturated absorption rate of 94.1%,and floating rate of 49.4% and water absorption rate of 89.2% were found in the kelp residues with particle size of 0.9 mm and corn flour addition of 30% in mass. The findings indicated that stearic acid led to increase the floating rate and to decrease the water absorption rate of the modified kelp residues, while the oil-absorbing rate was decreased with the increase in corn flour supplementation. The higher oil absorption and floating rate were observed in the extruded kelp residues with smaller particle size and sufficient reaction time, though the water absorption ratio was slightly higher. The oil absorption rate of 217.5%, floating rate of 94.3%, ratio of oil absorption rate to saturated absorption rate 94.0%, and water absorption rate of below 31.0% were found in the modified kelp residues with 0.9 mm particle size and modified for 2 h by addition of stearic acid at a rate of 8.5%. It was found that the modified kelp residues showed 1.52 times higher oil absorption ratio, and 1.91 times higher floating rate than the extruded kelp residues did, the water absorption rate being decreased by 65.2%.
2014, Vol. 29 
