Ecological studies of economic red algae. IV. Variations of carrageenan concentration and properties in Chondrus crispus Stackhouse

The concentration, gel strength, viscosity, and ratio of kappa to lambda fractions of carrageenan in Chondrus crispus Stackhouse have been studied in relation to age, reproduction, habitat, and season of harvesting. No correlation was found between gel strength and viscosity, but gel strength and the ratio of the fractions showed a direct relationship. Plant age, reproduction, and exposure to wave action had no effect on the quantity or properties of carrageenan. Sublittoral populations of Chondrus had higher viscosities and carrageenan concentrations than littoral plants; gel strengths showed an opposite trend. The amount of carrageenan, gel strength, and the size of the kappa fractions were usually greater in plants of coastal rather than estuarine locations: in contrast, estuarine plants exhibited higher viscosities than coastal plants. Carrageenan concentration, gel strength, and viscosity were highest in late fall-early winter, while the lowest values were recorded during the spring-early summer