Abstract
The effect of molar substitution (MS, 0.030-0.118) on the dynamic rheological properties of hydroxypropylated rice starch pastes (5%, w/w) was investigated by small-deformation oscillatory measurements during aging. The magnitudesof storage (G′) and loss (G″) moduli measured at 4°C before aging increased with an increase in MS in the range of 0.030-0.118, while those of tan 8 (the ratio of G″/G′) decreased. The Ǵ values of hydroxypropylated rice starches, as a Junction of aging time (10 hr) at 4°C, increased rapidly at the initial stage, and then reached a plateau region at shorter aging times. However, for the native starch, the plateau values were not observed forW G′ after a long aging time. Increasing the MS resulted in a decrease in plateau values. The rate constant (K) for structure development during aging was described by first-order kinetics. The K values of hydroxypropylated rice starches at 0.086and0.118 MS were much lower than the K value at 0.030 MS.
| Original language | English |
|---|---|
| Pages (from-to) | 584-587 |
| Number of pages | 4 |
| Journal | Korean Journal of Food Science and Technology |
| Volume | 39 |
| Issue number | 5 |
| State | Published - 2007 |
Keywords
- Hydroxypropylation
- Rheology
- Rrice starch
- Storage modulus
- Words