Synergistic interaction between kappa-carrageenan isolated from Hypnea charoides LAMOUROUX and galactomannan on its gelation

The synergistic effects on rheological properties for a series of aqueous s olution of kappa-carrageenan isolated from Hypnea charoides LAMOUROUX and g alactomannan (locust-bean gum) were investigated. At a concentration of 0.4 % of total gums, gelation did not occur at room temperature, but it did at a low temperature (0 degrees C). The maximum dynamic modulus was obtained w ith a series of the samples composed of K-salt of kappa-carrageenan and loc ust-bean gum in the mixing ratio of 1:1 at low temperature (0 degrees C). T he less synergistic effect on the dynamic modulus was obtained in mixture s olutions with Na-salt of kappa-carrageenan and locust-bean gum. At about 25 degrees C, gel-sol transition was observed in the mixing ratio of kappa-ca rrageenan (K-salt) to locust-bean gum of 3:1 and 4:1. A possible associatio n site between K-salt of kappa-carrageenan and locust-bean gum was proposed . (C) 1999 Canadian Institute of Food Science and Technology. Published by Elsevier Science Ltd. All rights reserved.