Abstract
Viscoelastic properties of sweet potato starch (SPS) pastes (5% w/w) were studied in the presence of various sugars (sucrose, glucose, fructose, and xylose) at different concentrations (0, 10 and 20%) by small-deformation oscillatory measurements. Dynamic frequency sweeps at 20°C indicated that all SPS-sugar mixtures were more elastic than viscous with storage moduli (G') higher than loss moduli (G") at all values of frequency with a frequency dependency. Dynamic moduli (G' and G") values increased with the increase in sugar concentration from 10 to 20%. Changes in the dynamic moduli were more pronounced with xylose in comparison to the control (no sugar) and other sugars. G' values as a function of ageing time (10 h) at 4°Ccontinuously increased with time during ageing without a plateau region. In general, G' values of SPS-sugar mixtures during ageing decreased in the following order: pentose (xylose) > hexose (glucose and fructose) > control > disaccharide (sucrose), indicating that the xylose had the greatest ability in retarding retrogradation of SPS.
Original language | English |
---|---|
Pages (from-to) | 410-414 |
Number of pages | 5 |
Journal | International Journal of Food Science and Technology |
Volume | 45 |
Issue number | 2 |
DOIs | |
State | Published - Feb 2010 |
Keywords
- Dynamic properties
- Rheology
- Sugar
- Sweet potato starch
- Viscoelasticity