The Experts below are selected from a list of 285 Experts worldwide ranked by ideXlab platform
William L. Kerr - One of the best experts on this subject based on the ideXlab platform.
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Water mobility and textural properties of native and hydroxypropylated wheat starch gels
Carbohydrate Polymers, 2003Co-Authors: S.g Choi, William L. KerrAbstract:Abstract The effect of wheat starch concentration and degree of hydroxypropylation on the water dynamics and textural attributes of starch gels was studied using 1 H NMR and texture profile analysis. Starches were prepared with molar substitution (MS) of hydroxypropyl groups of 0.05, 0.12, and 0.18. Gels were formed from modified starches at concentrations between 25 and 40%. For all gels, two distinct water fractions were identified using distributed exponential analysis of transverse relaxation results. For the less mobile fraction, T 2a ranged from 2 to 6 ms, while for the more mobile state, T 2b ranged from 20 to 200 ms. Values of both T 2a and T 2b increased with Increasing Moisture Content and hydroxypropyl MS. Control experiments indicated that more mobile states could be associated with both the extragranular amylose gel, as well as intragranular amylopectin-rich gel. The less mobile state was associated only with granule remnants. Gel hardness decreased significantly with Increasing Moisture Content, and with Increasing hydroxypropylation. Cohesiveness increased with degree of hydroxypropylation. Results from multi-regression analysis between hardness and NMR parameters showed that the mobility and amount of water in the less mobile state was most related to gel hardness.
Fojan Badii - One of the best experts on this subject based on the ideXlab platform.
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Accelerated ageing of wheat grains: Part II-influence on thermal characteristics of wheat starch and FTIR spectroscopy of gluten
Journal of Cereal Science, 2017Co-Authors: Abdolhossein Aghababaei, Amirhossein Elhamirad, Neda Maftoonazad, Fojan BadiiAbstract:Wheat quality characteristics are influenced by different factors such as Moisture Content, storage time and temperature. In this study accelerated ageing of wheat grains was carried out by Increasing Moisture Content (16, 18 and 20%) and keeping the samples in different temperatures (30, 40 and 50 °C) for different periods (2, 5 and 8 days). After milling, the thermal properties of starch and structure of gluten were investigated using Differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR); respectively. The experimental set up was designed using response surface methodology and the three distinct factors were combined by central composite design. Results showed that Increasing Moisture Content caused a decrease in onset, peak and end set temperatures of gelatinization while Increasing storage time and temperature increased these parameters. By progressing storage time the band intensity of thiol groups decreased while that of disulfide groups of gluten increased indicating an improvement in gluten quality. Increasing Moisture Content from 16 to 20% and higher storage temperature (50 °C) decreased intensity of disulfide bands.
Marcus Karel - One of the best experts on this subject based on the ideXlab platform.
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Phase Transitions of Amorphous Sucrose and Frozen Sucrose Solutions
Journal of Food Science, 2006Co-Authors: Yrjo H Roos, Marcus KarelAbstract:Amorphous sucrose showed typical thermal transitions of amorphous materials. The temperatures of those transitions, glass transition, crystallization and melting, decreased with Increasing Moisture Content. The glass transition temperature of dry amorphous sucrose at 57°C was decreased to -46°C as the sucrose was plasticized with excess water. That value remained constant due to maximal freeze-concentration with 72-73% sucrose in the unfrozen matrix which showed ice melting at -34°C. Concentrated solutions may become supercooled resulting in partial freeze-concentration with resultant lowering of glass transition temperature.
S.g Choi - One of the best experts on this subject based on the ideXlab platform.
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Water mobility and textural properties of native and hydroxypropylated wheat starch gels
Carbohydrate Polymers, 2003Co-Authors: S.g Choi, William L. KerrAbstract:Abstract The effect of wheat starch concentration and degree of hydroxypropylation on the water dynamics and textural attributes of starch gels was studied using 1 H NMR and texture profile analysis. Starches were prepared with molar substitution (MS) of hydroxypropyl groups of 0.05, 0.12, and 0.18. Gels were formed from modified starches at concentrations between 25 and 40%. For all gels, two distinct water fractions were identified using distributed exponential analysis of transverse relaxation results. For the less mobile fraction, T 2a ranged from 2 to 6 ms, while for the more mobile state, T 2b ranged from 20 to 200 ms. Values of both T 2a and T 2b increased with Increasing Moisture Content and hydroxypropyl MS. Control experiments indicated that more mobile states could be associated with both the extragranular amylose gel, as well as intragranular amylopectin-rich gel. The less mobile state was associated only with granule remnants. Gel hardness decreased significantly with Increasing Moisture Content, and with Increasing hydroxypropylation. Cohesiveness increased with degree of hydroxypropylation. Results from multi-regression analysis between hardness and NMR parameters showed that the mobility and amount of water in the less mobile state was most related to gel hardness.
Abdolhossein Aghababaei - One of the best experts on this subject based on the ideXlab platform.
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Accelerated ageing of wheat grains: Part II-influence on thermal characteristics of wheat starch and FTIR spectroscopy of gluten
Journal of Cereal Science, 2017Co-Authors: Abdolhossein Aghababaei, Amirhossein Elhamirad, Neda Maftoonazad, Fojan BadiiAbstract:Wheat quality characteristics are influenced by different factors such as Moisture Content, storage time and temperature. In this study accelerated ageing of wheat grains was carried out by Increasing Moisture Content (16, 18 and 20%) and keeping the samples in different temperatures (30, 40 and 50 °C) for different periods (2, 5 and 8 days). After milling, the thermal properties of starch and structure of gluten were investigated using Differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR); respectively. The experimental set up was designed using response surface methodology and the three distinct factors were combined by central composite design. Results showed that Increasing Moisture Content caused a decrease in onset, peak and end set temperatures of gelatinization while Increasing storage time and temperature increased these parameters. By progressing storage time the band intensity of thiol groups decreased while that of disulfide groups of gluten increased indicating an improvement in gluten quality. Increasing Moisture Content from 16 to 20% and higher storage temperature (50 °C) decreased intensity of disulfide bands.
