• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.1
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• pp.37-43
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• 1985

The present investigations were carried out for the purpose of making clear the fundamental features of the compositional difference of agarose and agaropectin in agar prepared from Gellidium amansii collected in different places and seasons, and its effect on properties of agar. The samples, Gellidium amansii, was collected every month from the same locality on the coast of the Ilgwang-myon, Yangsan-gun, Kyongnam, from March 1982 to February 1983. In addition, agarose and agaropectin in agar were isolated by dimethyl sulfoxide. The results obtained were summarized as follows : 1. In seasonal variation, the maximum yield of agar noted from spring through summer, and the minimum in February. 2. The experiment showed that the agarose and agaropectin composition in agar was changed, even if the seaweed collected from the same season was used as raw material. Seasonal variation of agarose and agaropectin contents in agar, the highest content occurred in August, $76.2\%$, and the lowest in January, $50.1%$. 3. Jelly strength, gelation ability of agar tended to increase as the agarose content was risen, but sulfate content was decreased.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.5
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• pp.716-721
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• 1996

To bring out the functional properties of Agar-agar extracted with 0.01N $H_2SO_4$ from Gellidium amansii produced in Che-ju Udo and its fluid properties were investigated. The yield of agar from Gellidium amansii produced was $32.7\%$, the content ratio of agarose and agaropectin was 79 to 21, gelation ability was $0.19\%$ and jelly strength was $413.8\;dyne/cm^2$. Agar-agar solution showed the movement of non-Newtonian fluid and pseudoplastic property was emerged as its concentration go higher. The yield stresses in the range of $0.5\~5\%$ agar-agar solution were $0.09\~1.21\;dyne/cm^2\;at\;80^{\circ}C,\;0.12\~5.29\;dyne/cm^2\;at\;60^{\circ}C\;and\;4.84\~58.37\;dyne/cm^2\;at\;50^{\circ}C$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.5
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• pp.722-726
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• 1996

To bring out the functional properties of Agar-agar extracted with 0.01N $H_2SO_4$ from Cellidium amansii produced in Che-ju Udo and its rheological properties were investigated. The flow behavior indexes in the range of $0.5\~5\%$ agar-agar solution were $0.62\~0.69\;at\;80^{\circ}C,\;0.46\~0.67\;at\;60^{\circ}C\;and\;0.34\~0.64\;at\;50^{\circ}C$. The consistency indexes were $0.12\~1.26\;Pa{\cdot}s^n\;at\;80^{\circ}C,\;0.12\~7.28\;Pa{\cdot}s^n\;at\;60^{\circ}C\;and\;3.9\~19952.6\;Pa{\cdot}s^n\;at\;50^{\circ}C$. Consistenry index's existence nature to concentration is two straight line relation which have different slopes on the border of $2\%$ concentration of agar-agar solution and existence nature of temperature followed Arrhenius equation. And the activation energy, in the range of $0.5\%\~5\%$ agar-agar solution, were $0.09\~13.51\;kcal/g{\cdot}mol$.