Characterization of non-linear rheological behavior of SPI-FG dispersions using LAOS tests and FT rheology
- Authors: Bi, Chonghao , Li, Dong , Wang, Li-jun , Wang, Yong , Adhikari, Benu
- Date: 2013
- Type: Text , Journal article
- Relation: Carbohydrate Polymers Vol. 92, no. 2 (2013), p. 1151-1158
- Full Text: false
- Reviewed:
- Description: The effect of flaxseed gum (FG) on the rheological and nonlinear stress response behaviors of mixed soy protein isolate (SPI)-flaxseed gum (FG) dispersions were studied. Results showed that the viscosity of the SPI-FG mixed dispersions increased significantly with increase in the FG concentration. Both the shear stress and the apparent viscosity values as a function of shear rate were fitted well using Power law model as expected. The frequency dependence of G′, G′′ and tan δ of soy protein isolate decreased as the FG concentration increased. The large amplitude oscillatory shear (LAOS) test and Fourier transform (FT) rheology analysis showed that the addition of flaxseed gum strongly affected the structure of the SPI-FG mixed dispersion system as shown by deformation of the nonlinear stress response curve and significantly altered magnitude of higher harmonic curve. The addition of FG increased the instantaneous strain softening effect of the SPI-FG mixed dispersion system. © 2012 Elsevier Ltd.
- Description: 2003011034
Effects of partial gelatinization on structure and thermal properties of corn starch after spray drying
- Authors: Fu, Zong-qiang , Wang, Li-jun , Li, Dong , Adhikari, Benu
- Date: 2012
- Type: Text , Journal article
- Relation: Carbohydrate Polymers Vol. 88, no. 4 (2012), p. 1319-1325
- Full Text: false
- Reviewed:
- Description: Partially gelatinized starch was prepared by gelatinizing corn starch at 64-72°C followed by spray drying (inlet temperature, feed flow rate, air flow rate of 200°C, 7.2 ml/min and 0.375 m 3/h, respectively). The morphology, granule size, crystalline fraction, swelling power and gelatinizing properties of partially gelatinized starch were investigated and compared with those of native starch. The surface morphology of partially gelatinized starch granules was shriveled with multiple surface folds. The granule size of partially gelatinized starch was smaller than that of native corn starch. There was either complete absence of crystalline fraction in partially gelatinized starch or the extent of crystalline fraction was greatly reduced. The swelling power of partially gelatinized starch was higher than that of the native starch below 60°C, while it was lower than that of native starch above 60°C. There was an increase in gelatinization temperature and a decrease in gelatinization enthalpy in partially gelatinized starch compared to that of native starch. © 2012 Elsevier Ltd. All rights reserved.
Optimization of production yield and functional properties of pectin extracted from sugar beet pulp
- Authors: Lv, Cheng , Wang, Yong , Wang, Li-jun , Li, Dong , Adhikari, Benu
- Date: 2013
- Type: Text , Journal article
- Relation: Carbohydrate Polymers Vol. 95, no. 1 (2013), p. 233-240
- Full Text: false
- Reviewed:
- Description: A central composite design was employed to determine the optimum extraction condition to obtain higher yield, better color attribute as well as better rheological and emulsifying properties in pectin extracted from sugar beet pulp (SBP). A second-order polynomial model was developed for predicting the yield of sugar beet pulp pectin (SBPP) based on the composite design. Response surface methodology (RSM) was used to quantify the integral effect of three processing parameters (extraction temperature, time and pH) on yield, yield stress, color attribute (tint value) and emulsifying activity index (EAI). Through the frequency analysis it was found that the optimal temperature, time and pH value of the extraction were 93.7 °C, 3 h, and 1.21, respectively. The yield, yield stress and tint value of the SBPP extracted at the optimal condition were 24.45%, above 0.1 Pa and -6.0, respectively. © 2013 Elsevier Ltd.
- Description: 2003011020
Characterization of starch films containing starch nanoparticles Part 1: Physical and mechanical properties
- Authors: Shi, Aimin , Wang, Li-Jun , Li, Dong , Adhikari, Benu
- Date: 2013
- Type: Text , Journal article
- Relation: Carbohydrate Polymers Vol. 96, no. 2 (2013), p. 593-601
- Full Text: false
- Reviewed:
- Description: We report, for the first time, the preparation method and characteristics of starch films incorporating spray dried and vacuum freeze dried starch nanoparticles. Physical properties of these films such as morphology, crystallinity, water vapor permeability (WVP), opacity, and glass transition temperature (Tg) and mechanical properties (strain versus temperature, strain versus stress, Young's modulus and toughness) were measured. Addition of both starch nanoparticles in starch films increased roughness of surface, lowered degree of crystallinity by 23.5%, WVP by 44% and Tg by 4.3 °C, respectively compared to those of starch-only films. Drying method used in preparation of starch nanoparticles only affected opacity of films. The incorporation of nanoparticles in starch films resulted into denser films due to which the extent of variation of strain with temperature was much lower. The toughness and Young's modulus of films containing both types of starch nanoparticles were lower than those of control films especially at <100 °C. © 2012 Elsevier Ltd. All rights reserved.
- Description: C1
Suspensions of vacuum-freeze dried starch nanoparticles : Influence of NaCl on their rheological properties
- Authors: Shi, Aimin , Wang, Li-jun , Li, Dong , Adhikari, Benu
- Date: 2013
- Type: Text , Journal article
- Relation: Carbohydrate Polymers Vol. 94, no. 2 (2013), p. 782-790
- Full Text: false
- Reviewed:
- Description: The effect of addition of NaCl on rheological properties of suspensions containing vacuum freeze dried starch nanoparticles was studied. These starch nanoparticles were produced through high pressure homogenization and emulsion cross-linking technique. Rheological properties such as continuous shear viscosity, storage and loss moduli and creep-recovery were measured. The presence of NaCl at concentration (5-15%, w/v) increased viscosity marginally (p > 0.05) while at 20% (w/v) it significantly (p < 0.05) increased viscosity. The presence of NaCl enhanced heat stability and weakened gelling capacity of suspensions. NaCl concentration below 15% (w/v) marginally (p > 0.05) increased the storage and loss moduli of suspensions. At 20% (w/v), NaCl increased both moduli significantly (p < 0.05) within frequency range tested (0.1-10 rad/s). Creep-recovery behavior was affected by NaCl and recovery rate was the highest (98.6%) at 20% (w/v) NaCl. The Cross, Power Law and Burgers' models followed experimental shear viscosity, storage and loss moduli and creep-recovery data reasonably well ((R
- Description: 2003010855
The effect of annealing and cryoprotectants on the properties of vacuum-freeze dried starch nanoparticles
- Authors: Shi, Aimin , Wang, Li-Jun , Li, Dong , Adhikari, Benu
- Date: 2012
- Type: Text , Journal article
- Relation: Carbohydrate Polymers Vol. 88, no. 4 (2012), p. 1334-1341
- Full Text: false
- Reviewed:
- Description: Starch nanoparticles prepared through high pressure homogenization and mini-emulsion cross-linking technology were successfully vacuum-freeze dried. Annealing process was introduced in the drying process and the cryoprotectants (lactose and mannitol) were used in the sample matrix. The effect of the annealing and cryoprotectants on the moisture content, glass transition temperature (T-g), amorphous/crystalline nature, particle size, morphology and the redispersibility of these nanoparticles was investigated. The residual moisture content of the nanoparticles was 4-9% (w/w) and it was lower in samples which were unannealed and contained cryoprotectants. Mannitol as cryprotectant resulted into starch nanoparticles with uniform spherical shape. The T-g of these nanoparticles varied from 52 degrees C to 57 degrees C and the difference was due to annealing and cryoprotectants. The annealing process and the presence of cryoprotectant did not hugely affect the X-ray diffraction pattern and FT-IR spectra which revealed the fully cross-linked and amorphous glassy state of starch nanoparticles. (C) 2012 Elsevier Ltd. All rights reserved.