Effect of galactomannan addition on the thermal behaviour of kappa-carrageenan gels

• Type: Article in International Scientific Journal
• Date: 1992

Authors

P. Fernandes (Author) Other; Maria do Pilar Gonçalves (Author) FEUP; J. Doublier (Author) Other

Journal

Title: Carbohydrate Polymers

No. 19

Pages: 261-269

ISSN: 0144-8617

Publisher: Elsevier

Scientific classification

FOS: Engineering and technology > Other engineering and technologies

Other information

Resumo (PT): Gelation/melting cycles of K-carrageenan/galactomannan (guan tara and locust bean gums) binary systems have been studied by measuring dynamic rheological parameters. Two experimental conditions were used (i) the total polysaccharide concentration was kept at 1% and the K-carrageenan/galacto-mannan ratio fixed at 4:1 and (ii) the K-carrageenan concentration was fixed at 0.75% and the galactomannan content varied from 0% to 1.2%. A thermal hysteresis was observed for all mixed systems and was found to depend on the galactomannan used. From a comparison of the gelation temperature (Tg) and melting temperature (Tm) to values obtained with K-carrageenan alone, it was suggested that galactomannan interferes with gel structure by the formation of a secondary network provided that the M/G ratio is high enough.

Abstract (EN): Gelation/melting cycles of K-carrageenan/galactomannan (guan tara and locust bean gums) binary systems have been studied by measuring dynamic rheological parameters. Two experimental conditions were used (i) the total polysaccharide concentration was kept at 1% and the K-carrageenan/galacto-mannan ratio fixed at 4:1 and (ii) the K-carrageenan concentration was fixed at 0.75% and the galactomannan content varied from 0% to 1.2%. A thermal hysteresis was observed for all mixed systems and was found to depend on the galactomannan used. From a comparison of the gelation temperature (Tg) and melting temperature (Tm) to values obtained with K-carrageenan alone, it was suggested that galactomannan interferes with gel structure by the formation of a secondary network provided that the M/G ratio is high enough.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9