Seasonal Variation of Fish Catch by a Set Net in Hamdeuk Fishing Ground off Jeju Island

摘要

In preparing sodium alginates from sea tangle (Laminaria japonica) powder using the Mexican process, alkaline extraction, conversion to alginic acid and reversion to sodium alginates were used to increase purity. The effect of hot water treatment and dialysis on measuring the average molecular weight of sodium alginates were investigated. Intrinsic viscosity and average molecular weight of sodium alginates after dialysis were higher than those before dialysis. Average molecular weight of sodium algi nates treated with hot water was higher than that without. Hot treatment has little effect on the ash content of sodium alginates. Ash content of sodium alginates before dialysis were 27-30%; those after dialysis were 10%. After dialysis, Na content was highest (89-91%), K was 11-12%, Ca was 1.9%, and Mg was 0.05%. Ash content of alginates had little effect on average molecular weight SAV (slope of apparent viscosity) of alginates solution after dialysis showed higher values than before SAV of the algin ates with hot water treatment were higher than without treatment.