Structure formation in sodium κ-carrageenan solutions

• Published in: Carbohydrate polymers Vol. 9; no. 2; pp. 133 - 145
• Main Authors: Semenova, M.G., Plashchina, I.G., Braudo, E.E., Tolstoguzov, V.B.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 1988; Elsevier Science
• Subjects: Biological and medical sciences; Food additives; Food industries; Fundamental and applied biological sciences. Psychology; General aspects; Structure
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/0144-8617(88)90010-0

The methods of elastic light scattering and polarimetry were used to estimate the molecular weight, second virial coefficient and radius of gyration of the dissolved particles as well as the conformational state of the sodium κ-carrageenan macromolecules in a solution of 0·1 m NaCl with respect to temperature. The process of aggregation of the macromolecules on cooling the diluted solutions was found to occur in two stages. The first stage consists of the association of disordered macromolecules, involving a two-fold decrease in the refractive index increment. The second, low-temperature stage of aggregation is the association of helical macromolecules. The data obtained do not contradict the ideas of the formation of double helices during the κ-carrageenan conformational transition.