Changes in the physical properties of xanthan gum induced by a dynamic high-pressure treatment
| Autor: | Sandra I. Laneuville, Sylvie L. Turgeon, Paul Paquin |
|---|---|
| Rok vydání: | 2013 |
| Předmět: |
Materials science
Polymers and Plastics Intrinsic viscosity Microfluidics 02 engineering and technology 010402 general chemistry 01 natural sciences Rheology Pressure Materials Chemistry medicine Composite material Birefringence Viscosity Polysaccharides Bacterial Organic Chemistry 021001 nanoscience & nanotechnology 0104 chemical sciences Molecular Weight Shear (sheet metal) Freeze Drying Cavitation Flow birefringence Degradation (geology) 0210 nano-technology Xanthan gum medicine.drug |
| Zdroj: | Carbohydrate Polymers. 92:2327-2336 |
| ISSN: | 0144-8617 |
| Popis: | The effect of microfluidization, a dynamic high pressure treatment, on xanthan gum was investigated in views of enlarging its potential applications. Samples were characterized chemically and physically (molecular weight, intrinsic viscosity, flow behavior and flow induced birefringence). Particular interest was given to the correlation between the level of degradation and aggregate content to the flow behavior and flow-induced birefringence. A mechanism of degradation is proposed: initially, microfluidization reduces the aggregated state of xanthan and may even be able to dissociate the double helical structure into single chains; upon increasing treatment severity, a relatively mild degradation of the main chain can be achieved. Interestingly, samples treated at high ionic strengths were more sensitive to mechanical degradation, arguably since stiffer molecules in the ordered conformation presented a larger exposed surface and thus experienced stronger effective stresses when subjected to the high shear and cavitation forces present in the microfluidization chamber. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect