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Shujun Wang - One of the best experts on this subject based on the ideXlab platform.
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Insights into the Starch Gelatinization behavior inside intact cotyledon cells.
International journal of biological macromolecules, 2020Co-Authors: Peng Guo, Shuo Wang, Shujun WangAbstract:Abstract In this work, detailed structural changes of Starch within intact cotyledon cells during differential scanning calorimetry (DSC) heating (water: cells ratio of 4:1, v/w) were investigated. Intact cotyledon cells containing raw Starch granules from three legumes were isolated and used as materials, followed by simulate DSC heating up to different designated temperatures based on those Gelatinization profiles of cells. The swelling power, solubility and Gelatinization transition parameters of raw cells were significantly lower than pure Starches. Upon simulate heating, all the Starches inside intact cells were considered to maintain more amounts of crystalline and double-helix structures than pure Starch counterparts. Meanwhile, the Starch granules were not completely disrupted even heating up to 15 °C above conclusion temperature (Tc + 15 °C) for intact cells. The results showed clearly that the presence of intact cell wall exerts significant retarding or restricting effects on the process of Starch Gelatinization.
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New insights into Starch Gelatinization by high pressure: Comparison with heat-Gelatinization.
Food chemistry, 2020Co-Authors: Yi Liu, Shujun Wang, Shuo Wang, Chen Chao, Les CopelandAbstract:The effects of pressure and temperature on the Gelatinization properties of wheat Starch were investigated. The long-range crystallinity and short-range molecular order were gradually destroyed under both conditions as the degree of Gelatinization (DG) increased. With increasing DG, differential scanning calorimetry (DSC) onset (To), peak (Tp) and conclusion temperatures (Tc) increased for the heat-gelatinized samples but did not change greatly for the pressure-gelatinized samples. At similar DG, pressure-Gelatinization resulted in less granule swelling than heat-Gelatinization. Lower degree of both heat- and pressure-Gelatinization resulted in increased pasting viscosities and gel texture parameters, whereas the opposite was noted at higher DG. We conclude that pressure and heat induced Starch Gelatinization in different ways, resulting in different gel texture properties. Pressure-Gelatinization disrupted both less stable and more stable crystallites, whereas less stable crystallites were preferentially disrupted during heat-Gelatinization.
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Mechanisms of Starch Gelatinization during heating of wheat flour and its effect on in vitro Starch digestibility
Food Hydrocolloids, 2018Co-Authors: Peng Guo, Les Copeland, Shuo Wang, Shujun WangAbstract:Abstract This study aimed to understand mechanisms of Starch Gelatinization during heating of wheat (Triticum aestivum L.) flour, and its effects on in vitro Starch amylolysis of cooked wheat flour. At water content of 20%, cooking did not disrupt greatly the crystalline structures of Starch in wheat flour. Considerable disruption of ordered structures of Starch occurred with cooking at a water content of 30%, and Starch was fully gelatinized at a water content of 40%. The transition of the X-ray diffraction pattern from A to V types with increasing water content suggested the formation of Starch-lipid complexes during cooking of flour. Typical Starch pasting profiles of cooked wheat flour were observed at water contents of 40 and 50%, whereas longer cooking time decreased the pasting viscosities of the flour. Cooking the flour for only 5 min with 20% water greatly increased the rate and extent of in vitro enzymatic digestion of Starch, which were not increased further by longer cooking or higher water content. From this study, we conclude that the progression of Starch Gelatinization during cooking was not greatly affected by non-Starch components in wheat flour, and that some structural order in amorphous regions of Starch contributed to the development of pasting viscosities.
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Changes of multi-scale structure during mimicked DSC heating reveal the nature of Starch Gelatinization
Scientific reports, 2016Co-Authors: Shujun Wang, Xiu Zhang, Shuo Wang, Les CopelandAbstract:A thorough understanding of Starch Gelatinization is extremely important for precise control of Starch functional properties for food processing and human nutrition. Here we reveal the molecular mechanism of Starch Gelatinization by differential scanning calorimetry (DSC) in conjunction with a protocol using the rapid viscosity analyzer (RVA) to generate material for analysis under conditions that simulated the DSC heating profiles. The results from DSC, FTIR, Raman, X-ray diffraction and small angle X-ray scattering (SAXS) analyses all showed that residual structural order remained in Starch that was heated to the DSC endotherm end temperature in Starch:water mixtures of 0.5 to 4:1 (v/w). We conclude from this study that the DSC endotherm of Starch at a water:Starch ratio of 2 to 4 (v/w) does not represent complete Starch Gelatinization. The DSC endotherm of Starch involves not only the water uptake and swelling of amorphous regions, but also the melting of Starch crystallites.
Pedro Bouchon - One of the best experts on this subject based on the ideXlab platform.
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the effect of vacuum frying on Starch Gelatinization and its in vitro digestibility in Starch gluten matrices
Food Chemistry, 2016Co-Authors: Ingrid Contardo, Javier Parada, Angel Leiva, Pedro BouchonAbstract:Abstract Starch digestibility in a food matrix depends on processing conditions that may affect its physical state and microstructure. Starch Gelatinization is one critical change that takes place during frying which could be affected during low-pressure processing. This study assessed the effect of vacuum frying on Starch Gelatinization and its in vitro digestibility. Laminated dough was made of a reconstituted blend of wheat Starch (88% d.b.) and gluten (12% d.b.). Samples were fried under vacuum (6.5 kPa, T water-boiling-point = 38 °C) or atmospheric conditions up to bubble-end point, maintaining a thermal driving force of 70 °C ( T oil − T water-boiling-point = 70 °C). Vacuum fried samples showed less Starch Gelatinization (28%), less rapidly available glucose (27%), and more unavailable glucose (70%) than their atmospheric counterparts (which presented 99% Starch Gelatinization, 40% rapidly available glucose , and 46% unavailable glucose ), and the values were close to those of raw dough. These results show how vacuum processing may be used to control the degree of Starch Gelatinization and related digestibility.
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Examining the effect of freezing on Starch Gelatinization during heating at high rates using online in situ hot-stage video-microscopy and differential scanning calorimetry
Food and Bioproducts Processing, 2016Co-Authors: M.t. Molina, A. Leiva, Pedro BouchonAbstract:Abstract Despite its importance, little attention has been paid to the effect of freezing on Starch Gelatinization during subsequent heating. In an effort to address this problem, the effects of freezing and water accessibility in Starch Gelatinization during heating were analyzed in situ using hot-stage polarized-light video-microscopy. Native Starch granules immersed in water, carrageenan gel or sucrose solution were heated at 15 °C/min or frozen for 48 h and heated at 15 °C/min. Energy changes were measured using differential scanning calorimetry. Surface morphology was examined using scanning electron microscopy and atomic force microscopy. The results showed that freezing delayed the Gelatinization degree and that the addition of carrageenan delayed the Gelatinization process. That process was further delayed when sucrose was added. The enthalpy of Gelatinization decreased accordingly (ΔHStarch−water−sucrose > ΔHStarch−water−carrageenan > ΔHStarch−water). The temperature range over which the degree of Gelatinization differed between frozen and unfrozen samples was diminished when accessibility to water was reduced.
Stanislaw L. Randzio - One of the best experts on this subject based on the ideXlab platform.
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Water content influence on thermal and volumetric properties of wheat Starch Gelatinization under 10 MPa
Annals of the New York Academy of Sciences, 2010Co-Authors: Marta Orlowska, Stanislaw L. RandzioAbstract:A transitiometric in situ analysis of wheat Starch aqueous suspensions heated over a temperature range from 285 K to 415 K under isobaric conditions of 10 MPa is presented. Measurements were performed at four selected water concentrations: 56.0%, 64.7%, 73.5%, and 82.4% weight/water. Thermal and volumetric properties and their water content dependencies have been determined for three successive Starch phase transformations occurred during wheat Starch Gelatinization.
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Simultaneous and in situ analysis of thermal and volumetric properties of Starch Gelatinization over wide pressure and temperature ranges.
Biomacromolecules, 2005Co-Authors: Stanislaw L. Randzio, Marta OrlowskaAbstract:A method for simultaneous and in situ analysis of thermal and volumetric properties of Starch Gelatinization from 0.1 to 100 MPa and from 283 to 430 K is described. The temperature of a very sensitive calorimetric detector containing a Starch-water emulsion at a selected pressure is programmed to rise at a slow rate; volume variations are performed automatically to keep the selected pressure constant while the heat exchange rate and the volume are recorded. The method is demonstrated with a novel investigation of pressure effects on a sequence of three phase transitions in an aqueous emulsion of wheat Starch (56 wt % water). The volume changes during the main endothermic transition (M), associated with melting of the crystalline part of the Starch granules and a helix-coil transformation in amylopectin, but also with an important swelling, were separated into a volume increase associated with swelling and a volume decrease associated with the transition itself. Thermodynamic parameters for this transition together with their pressure dependencies have been obtained from four independent experiments at each pressure. The data are thermodynamically consistent, but are poorly described by the Clapeyron equation. The negative volume change of the slow exothermic transition (A) appearing just after the main endothermic transition (M) is small, spread out over a wide temperature interval, and occurs at higher temperatures with increasing pressures. This transition is probably associated with reassociation of the unwound helixes of amylopectin with parts of amylopectin molecules other than their original helix duplex partner. The positive volume change of the high-temperature, endothermic transition (N) with a small enthalpy change is probably associated with a nematic-isotropic transformation ending the formation of a homogeneous SOL phase (in the sense of Flory), and is also pushed to higher temperatures with increasing pressures. Knowledge of the state of wheat Starch as a function of pressure and temperature is important in extruder processing. The data also provide a basis for the elliptic phase diagram for Starch Gelatinization. The method is easily adapted to determine similar data for other macromolecular materials.
Marta Orlowska - One of the best experts on this subject based on the ideXlab platform.
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Water content influence on thermal and volumetric properties of wheat Starch Gelatinization under 10 MPa
Annals of the New York Academy of Sciences, 2010Co-Authors: Marta Orlowska, Stanislaw L. RandzioAbstract:A transitiometric in situ analysis of wheat Starch aqueous suspensions heated over a temperature range from 285 K to 415 K under isobaric conditions of 10 MPa is presented. Measurements were performed at four selected water concentrations: 56.0%, 64.7%, 73.5%, and 82.4% weight/water. Thermal and volumetric properties and their water content dependencies have been determined for three successive Starch phase transformations occurred during wheat Starch Gelatinization.
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Simultaneous and in situ analysis of thermal and volumetric properties of Starch Gelatinization over wide pressure and temperature ranges.
Biomacromolecules, 2005Co-Authors: Stanislaw L. Randzio, Marta OrlowskaAbstract:A method for simultaneous and in situ analysis of thermal and volumetric properties of Starch Gelatinization from 0.1 to 100 MPa and from 283 to 430 K is described. The temperature of a very sensitive calorimetric detector containing a Starch-water emulsion at a selected pressure is programmed to rise at a slow rate; volume variations are performed automatically to keep the selected pressure constant while the heat exchange rate and the volume are recorded. The method is demonstrated with a novel investigation of pressure effects on a sequence of three phase transitions in an aqueous emulsion of wheat Starch (56 wt % water). The volume changes during the main endothermic transition (M), associated with melting of the crystalline part of the Starch granules and a helix-coil transformation in amylopectin, but also with an important swelling, were separated into a volume increase associated with swelling and a volume decrease associated with the transition itself. Thermodynamic parameters for this transition together with their pressure dependencies have been obtained from four independent experiments at each pressure. The data are thermodynamically consistent, but are poorly described by the Clapeyron equation. The negative volume change of the slow exothermic transition (A) appearing just after the main endothermic transition (M) is small, spread out over a wide temperature interval, and occurs at higher temperatures with increasing pressures. This transition is probably associated with reassociation of the unwound helixes of amylopectin with parts of amylopectin molecules other than their original helix duplex partner. The positive volume change of the high-temperature, endothermic transition (N) with a small enthalpy change is probably associated with a nematic-isotropic transformation ending the formation of a homogeneous SOL phase (in the sense of Flory), and is also pushed to higher temperatures with increasing pressures. Knowledge of the state of wheat Starch as a function of pressure and temperature is important in extruder processing. The data also provide a basis for the elliptic phase diagram for Starch Gelatinization. The method is easily adapted to determine similar data for other macromolecular materials.
Paul Ainsworth - One of the best experts on this subject based on the ideXlab platform.
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effect of canning on the Starch Gelatinization and protein in vitro digestibility of tarhana a wheat flour based mixture
Journal of Food Engineering, 2004Co-Authors: Şenol İbanoğlu, Paul AinsworthAbstract:Tarhana, a fermented wheat flour–yoghurt mixture used in soup making, was produced in ready-to-eat form using canning. The effects of rotation speed (6.6–8.4 rpm), dry solids content (33.0–41.9% w/w) and retort time (3.20–3.80 min) on the Starch Gelatinization and protein in vitro digestibility (PIVD) of the samples were analysed using response surface methodology. Increasing rotation speed and retort time resulted in increased Starch Gelatinization (p>0.005). Rotation speed had more effect on Starch Gelatinization than retort time. Changes in dry solids content of the soup did not have any significant (p>0.005) effect on Starch Gelatinization. The PIVD values of the samples did not change significantly (p>0.05) in all canning conditions studied.
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Kinetics of Starch Gelatinization during extrusion of tarhana, a traditional turkish wheat flour-yogurt mixture.
International journal of food sciences and nutrition, 1997Co-Authors: Şenol İbanoğlu, Paul AinsworthAbstract:Tarhana, a traditional Turkish cereal food, was extruded at different extrusion conditions (product temperature: 60–120°C; screw speed: 100–300 rpm; feed rate: 10–20 kg/h). The mean residence time and corresponding degree of Starch Gelatinization data were used to estimate the order of reaction, Gelatinization rate constants and activation energy for Starch Gelatinization. Results indicate that Starch Gelatinization exhibited an apparent first-order reaction kinetics with a reaction order of approximately 0.8. Activation energy for Gelatinization was calculated as 3325 kJ/kg mol using the Arrhenius equation.
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Extrusion of tarhana : effect of operating variables on Starch Gelatinization
Food Chemistry, 1996Co-Authors: Şenol İbanoğlu, Paul Ainsworth, George D. HayesAbstract:Tarhana, a traditional Turkish cereal food, was extruded using a twin-screw extruder. The effect of barrel temperature (6–120 °C), feed rate (10–20 kg h−1, wet basis) and screw speed (100–300 rpm) on Starch Gelatinization was investigated using response surface methodology at constant moisture content (43%, wet basis). A regression equation for predicting Starch Gelatinization was developed. Barrel temperature had the most pronounced effect on Starch Gelatinization at constant moisture content, followed by feed rate and screw speed. Response surface plots suggest that a high degree of Starch Gelatinization can be achieved when tarhana is extruded at high barrel temperatures and screw speeds but low feed rates (i.e. high residence times).
