Intrinsic viscosity, steady and oscillatory shear rheology of a new source of galactomannan isolated from Gleditsia caspica (Persian honey locust) seeds in aqueous dispersions

• Published in: European food research & technology Vol. 247; no. 10; pp. 2579 - 2590
• Main Authors: Niknam, Rasoul, Mousavi, Mohammad, Kiani, Hossein
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.10.2021; Springer Nature B.V
• Subjects: Agriculture; Analytical Chemistry; Aqueous solutions; Biotechnology; Chemistry; Chemistry and Materials Science; Conformation; food research; Food Science; Forestry; galactomannans; Gleditsia caspica; Gleditsia triacanthos; Honey; hydrocolloids; Iran; Molecular conformation; Original Paper; Rheological properties; Rheology; Seeds; Shear flow; Shear rate; technology; Thickening agents; Viscosity; Iran; Steady shear flow; Oscillatory rheology; Galactomannan; Intrinsic viscosity; Rheological properties
• ISSN: 1438-2377; 1438-2385
• DOI: 10.1007/s00217-021-03818-7

Nowadays, hydrocolloids, especially galactomannans, are applied as thickening agents in food and pharmaceutical products. Gleditsia caspica , known as Persian honey locust, which is available in large quantities in the northern regions of Iran, is found to be rich in galactomannan. To better investigate the thickening properties, a complete research on the rheological features of galactomannan with different concentrations in aqueous solutions is of particular importance. The obtained results of steady shear flow experiments indicated that the stress–shear rate, apparent viscosity–shear rate, and stress-time data were well fitted with power law, Cross and Figuni–Shoemaker models according to their R 2 and RMSE values. Strain and frequency sweep experiment consequences demonstrated that the solutions containing 0.5 and 1% w/v galactomannan exhibited viscous-like behavior that is mainly associated with lack of strong interactions in the conformation and solutions containing 1.5% w/v galactomannan indicated gel-like behavior that is affiliated with more stable interactions between chains in the conformation. Intrinsic viscosity of obtained galactomannan was in the range of 6.7282–7.1722 dl/g.