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Ling Chen - One of the best experts on this subject based on the ideXlab platform.
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effect of pressure with shear stress on Gelatinization of starches with different amylose amylopectin ratios
Food Hydrocolloids, 2017Co-Authors: Hongsheng Liu, Xianyang Bao, Yanfei Wang, Ling ChenAbstract:Abstract Effect of pressure with shear stress on the Gelatinization of cornstarch with different amylose/amylopectin ratios (waxy 0/100; maze 23/77; G50 50/50; G80 80/20) was systematically investigated using a high-pressure rheometer. Onset and peak temperature of starch Gelatinization as well as the peak viscosity were used to discuss the influence of pressure together with shear stress on the Gelatinization of starch granules. The results showed that without shear stress, pressure could resist the Gelatinization process due to weak swelling of starch granules and lower quantity of amylose released. However, the shear stress can simply counteract the influence of the pressure since its impact is much high on Gelatinization. Under certain pressure and shear stress, both onset and peak temperatures of Gelatinization were increased with increasing amylose content, which is in correspondence with the results from differential scanning calorimeter measurement, while the overall viscosity was lower when starches with a higher amylose content was used because part of its granular was not fully dissolved during the measurement. SAXS measurements were used to study the gel structure and stability of starch suspensions. It was found that the scattering intensity of starches in the measured range (0.1–1.0 nm −1 ) is G80 > waxy, indicating the amount of ordered semi-crystalline structures in amylose is higher. Peak values, q = 0.4 nm −1 and q = 0.2 nm −1 , detected for waxy starch under different shear rates, indicates that higher shear stress which plays a dominant role compared with pressure, resulted in more degradation in amylopectin, inhibiting the formation of aggregate structure.
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internal structures and phase transitions of starch granules during Gelatinization
Carbohydrate Polymers, 2011Co-Authors: Pei Chen, George P Simon, Xingxun Liu, Katherine Dean, Ling ChenAbstract:The internal structures of corn starch granules with different amylose/amylopectin contents were studied using different microscopic techniques. The Gelatinization phase transitions of the various starches were investigated by hot-stage confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). The influence of the amylose/amylopectin ratio on the internal structures and morphologies could be revealed by these techniques. Sharp growth ring structures could be clearly identified for high-amylopectin starches by CLSM and SEM following acid treatment. CLSM allowed the visualization of cross-sections of starch granules without the need for sectioning techniques that lead to destruction of the microstructure of sample, allowing exploration of the Gelatinization mechanism. Three-dimensional images of starch granules during Gelatinization could be constructed to further explore phase transition mechanisms. It was found that the granules of waxy maize and normal maize starch subsequently break through at their cavity and channels, when the granules became swollen during Gelatinization, whilst the granules of G50 and G80 remain granular and break down to smaller pieces.
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starch Gelatinization under pressure studied by high pressure dsc
Carbohydrate Polymers, 2009Co-Authors: George P Simon, Hongsheng Liu, Katherine Dean, Eustathios Petinakis, Ling ChenAbstract:The Gelatinization process of waxy corn starch under different pressures up to 10.0 MPa was investigated using a high pressure DSC. Compressed air and carbon dioxide were used as pressure resources. Effect of pressure and annealing under pressure on Gelatinization of waxy corn starch was systematically studied, in particular on the Gelatinization temperature and enthalpy. The results show that the peak temperature of Gelatinization was increased slightly initially then remained stable with increasing pressure. The Gelatinization enthalpy was decreased under pressure processing. Annealing the starch under pressure condition, just below its Gelatinization temperature, increased Gelatinization temperature but kept gelatinized enthalpy constant. Morphologies of starch granules treated under pressure were studied using an optical microscope and SEM. There is no discernable difference of starch granules treated with and without pressure, which indicates the pressures are not high enough to destroy crystalline structure. The intensity of the pressure acts as a key factor to influence the Gelatinization of starch rather than the nature of the gas. Effect of pressure on the multi-endotherm detected by DSC for starch with intermediate water is used to study the mechanisms. The effect of pressure can be explained by the enhancement of water diffusion in the amorphous range.
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A new study of starch Gelatinization under shear stress using dynamic mechanical analysis
Carbohydrate Polymers, 2008Co-Authors: Fengwei Xie, Ling ChenAbstract:Abstract A new technique for studying starch Gelatinization under shear stress using dynamic mechanical analysis (DMA) with shear sandwich mode is reported. Rice starch was used as the model material in the experimental work. The physical meaning of storage modulus G ′ , loss modulus G ′′ and tangent of the phase angle tan δ , measured during starch Gelatinization, is discussed. The effects of various factors, such as sample preparation and measurement conditions, on the measured results are discussed. A sharp peak of tan δ was detected during heating starch, which well represents the starch Gelatinization process under shear stress. Comparison between the results detected by DMA and differential scanning calorimetry was used to interpret the processes and mechanisms of starch Gelatinization. Results showed that variations in physical properties occurred both before thermal transition started and after thermal transition was complete. DMA has proved to be a convenient technique to study starch Gelatinization under shear stress. One of the important advantages of this technique is it can be used to study starch Gelatinization at low moisture contents (⩽50%) under shear stress.
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Starch Gelatinization under shearless and shear conditions
International Journal of Food Engineering, 2007Co-Authors: Fengwei Xie, Ling Chen, Hongshen Liu, Pei Chen, Tao Xue, P. CorriganAbstract:This article reviews the development of studying starch Gelatinization under shear and shearless conditions, in particular the technologies used to detect the degree of Gelatinization. Advantages and disadvantages of each technology were discussed and then some examples were presented to demonstrate their application. A new technology RheoScope, an instrument that can measure viscosity under shear stress and simultaneously observes variation of starch particles using a microscope, was also introduced. It was found the definition of "Gelatinization" could be different for different detection technologies. Under shearless condition full Gelatinization of starch needs about ratio of water 3/starch 1, while the Gelatinization under shear condition requires less water content since shear stress enhances the processing. The number of endotherm and enthalpy of Gelatinization depends on amylose/amylopectin, moisture and lipid content.
Kazutaka Yamamoto - One of the best experts on this subject based on the ideXlab platform.
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effect of temperature on Gelatinization and retrogradation in high hydrostatic pressure treatment of potato starch water mixtures
Carbohydrate Polymers, 2012Co-Authors: Kiyoshi Kawai, Ken Fukami, Kazutaka YamamotoAbstract:Abstract The effect of temperature (20–70 °C) on the Gelatinization and retrogradation of potato starch–water mixtures (10–70%, w/w) treated with high hydrostatic pressure (HHP) (400–1000 MPa) was investigated. Gelatinization enthalpy change (Δ H gel ) and re-Gelatinization enthalpy change of retrograded crystalline part (Δ H retro ) of the HHP-treated starch were evaluated using differential scanning calorimetry. The value of Δ H gel of 10–20% (w/w) mixtures decreased with increased pressure and temperature, while Δ H gel of 30–50% (w/w) mixtures decreased to certain values with increased pressure and the values depended on treatment temperature. With higher temperature and pressure conditions, Δ H gel of 10–40% (w/w) mixtures reached zero, but Δ H gel of 50–70% (w/w) mixtures did not. Retrogradation was observed with HHP-treated 20–60% (w/w) mixtures and the value of Δ H retro depended on the starch content, pressure, and temperature. The value of Δ H retro trended to increase with increase in starch content. In addition, retrogradation was promoted by HHP treatment at low temperature. Gelatinizaiton and retrogradation behaviors of HHP-treated (400–1000 MPa) potato starch–water mixtures (10–70%, w/w) at 20–70 °C were summerized in a series of state diagrams.
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state diagram of potato starch water mixtures treated with high hydrostatic pressure
Carbohydrate Polymers, 2007Co-Authors: Kiyoshi Kawai, Ken Fukami, Kazutaka YamamotoAbstract:Potato starch-water mixture was treated with high hydrostatic pressure (HHP) of up to 1.2 GPa, and effect of starch content (10-70% (w/w)) on HHP-Gelatinization was investigated by differential scanning calorimetry (DSC). Depending on the treatment pressure and potato starch content, DSC thermograms showed decrease in enthalpy change of heat Gelatinization reflecting the progress of HHP-Gelatinization and increase in enthalpy change of re-Gelatinization of retrograded starch. From the viewpoint of the enthalpy changes, physically modified state of HHP-treated potato starch-water mixtures was classified as follows: no change, partial Gelatinization, complete Gelatinization, partial Gelatinization and retrogradation, and complete Gelatinization and retrogradation. A state diagram of potato starch-water mixtures (treatment pressure vs. starch content) was presented.
Hongsheng Liu - One of the best experts on this subject based on the ideXlab platform.
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A new characterization methodology for starch Gelatinization.
International journal of biological macromolecules, 2018Co-Authors: Jinxuan Tao, Peitao Zhu, Hongsheng Liu, Jie Xiao, Wutong Zhang, Shaobo ZhangAbstract:A Gelatinization degree control system, with a combination of Artificial Neural Networks (ANNs) and computer vision, was successfully developed. An intelligent measurement framework was purposely designed to achieve a precise investigation on phase transition and morphology change of starch in real time, as well as a process control during Gelatinization. Base on a variation of birefringence number, the degree of Gelatinization (DG) control system provided a direct and fast methodology without subjective uncertainty in studying starch Gelatinization. In the course, the whole system was a cascade structure with the hot-stage temperature chosen as the inner-loop parameter, thus the granule morphology and birefringence at different DG could be easily observed and compared in real time, and the relative transition temperature was simultaneously calculated.
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effect of pressure with shear stress on Gelatinization of starches with different amylose amylopectin ratios
Food Hydrocolloids, 2017Co-Authors: Hongsheng Liu, Xianyang Bao, Yanfei Wang, Ling ChenAbstract:Abstract Effect of pressure with shear stress on the Gelatinization of cornstarch with different amylose/amylopectin ratios (waxy 0/100; maze 23/77; G50 50/50; G80 80/20) was systematically investigated using a high-pressure rheometer. Onset and peak temperature of starch Gelatinization as well as the peak viscosity were used to discuss the influence of pressure together with shear stress on the Gelatinization of starch granules. The results showed that without shear stress, pressure could resist the Gelatinization process due to weak swelling of starch granules and lower quantity of amylose released. However, the shear stress can simply counteract the influence of the pressure since its impact is much high on Gelatinization. Under certain pressure and shear stress, both onset and peak temperatures of Gelatinization were increased with increasing amylose content, which is in correspondence with the results from differential scanning calorimeter measurement, while the overall viscosity was lower when starches with a higher amylose content was used because part of its granular was not fully dissolved during the measurement. SAXS measurements were used to study the gel structure and stability of starch suspensions. It was found that the scattering intensity of starches in the measured range (0.1–1.0 nm −1 ) is G80 > waxy, indicating the amount of ordered semi-crystalline structures in amylose is higher. Peak values, q = 0.4 nm −1 and q = 0.2 nm −1 , detected for waxy starch under different shear rates, indicates that higher shear stress which plays a dominant role compared with pressure, resulted in more degradation in amylopectin, inhibiting the formation of aggregate structure.
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starch Gelatinization under pressure studied by high pressure dsc
Carbohydrate Polymers, 2009Co-Authors: George P Simon, Hongsheng Liu, Katherine Dean, Eustathios Petinakis, Ling ChenAbstract:The Gelatinization process of waxy corn starch under different pressures up to 10.0 MPa was investigated using a high pressure DSC. Compressed air and carbon dioxide were used as pressure resources. Effect of pressure and annealing under pressure on Gelatinization of waxy corn starch was systematically studied, in particular on the Gelatinization temperature and enthalpy. The results show that the peak temperature of Gelatinization was increased slightly initially then remained stable with increasing pressure. The Gelatinization enthalpy was decreased under pressure processing. Annealing the starch under pressure condition, just below its Gelatinization temperature, increased Gelatinization temperature but kept gelatinized enthalpy constant. Morphologies of starch granules treated under pressure were studied using an optical microscope and SEM. There is no discernable difference of starch granules treated with and without pressure, which indicates the pressures are not high enough to destroy crystalline structure. The intensity of the pressure acts as a key factor to influence the Gelatinization of starch rather than the nature of the gas. Effect of pressure on the multi-endotherm detected by DSC for starch with intermediate water is used to study the mechanisms. The effect of pressure can be explained by the enhancement of water diffusion in the amorphous range.
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Gelatinization of cornstarch with different amylose amylopectin content
Carbohydrate Polymers, 2006Co-Authors: Hongsheng Liu, Fengwei Xie, Ling ChenAbstract:Gelatinization behaviours of cornstarch with different amylose/amylopectin content (waxy: 0/100, maize: 23/77, Gelose 50: 50/50 and Gelose 80: 80/20) were systematically studied by DSC using stainless steel high pressure pan as functions of water content (9-75%) and temperature (0-200 °C). The number of endotherm and enthalpy of Gelatinization depend on amylose/amylopectin, moisture and lipid content. A unique endotherm for the high amylose starch Gelose 80 was detected and labelled as M3. Gelatinization endotherms G, Ml and M2 in different cornstarches showed similar thermal behaviours and variation patterns. The enthalpy of Gelatinization was calculated individually and through summarization of all the Gelatinization endotherms. The Gelatinization enthalpy of amylopectin rich starch is higher than that of amylose rich starch. Total enthalpy of Gelatinization increased with increasing amylopectin and water contents.
Shujun Wang - One of the best experts on this subject based on the ideXlab platform.
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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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Gelatinization behavior of starch reflecting beyond the endotherm measured by differential scanning calorimetry
Food Chemistry, 2019Co-Authors: Yi Liu, Les Copeland, Shuo Wang, Shujun WangAbstract:Abstract In this study, the Gelatinization behavior of wheat starch was investigated using starch-water mixtures that were heated under different conditions. Heating starch-water mixtures at 50 °C, a temperature below onset temperature (To) of starch Gelatinization, resulted in disruption of long- and short-range ordered structure, as measured by differential scanning calorimetry, X-ray diffraction and laser confocal micro-Raman spectroscopy, and the extent of disruption was greater when starch was heated at higher water content. At low water content (23–44%), heating duration had little effect on Gelatinization behavior of starch, whereas at higher water content (54–75%), longer duration of heating resulted in greater disruption of multiscale structure of starch. From this study, we concluded that the Gelatinization endotherm of starch does not represent the complete Gelatinization behavior, and starch Gelatinization initiates earlier than To. Longer duration of heating caused a greater disruption of starch structure at high water content than at low water content.
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new insights into Gelatinization mechanisms of cereal endosperm starches
Scientific Reports, 2018Co-Authors: Shujun Wang, Shuo Wang, Chen Chao, Fengjuan Xiang, Xiu Zhang, Les CopelandAbstract:A thorough understanding of starch Gelatinization is needed to control starch functional properties for food processing and human nutrition. Here, we reveal the mechanism of structural disassembly of rice, maize and wheat starch granules during thermal transitions in which a Rapid Visco Analyzer (RVA) was used to pre-heat the starches to certain transition points in the differential scanning calorimetry (DSC) heating profiles. This was done to generate sufficient material for structural analyses. The results from DSC, Raman, X-ray diffraction and scanning electron microscopy (SEM) analyses all showed that at the conclusion temperature (Tc) of the DSC endotherm rice starch Gelatinization was complete, whereas residual structural order remained in maize and wheat starches. Gelatinization of wheat and maize starch was complete at a temperature higher than Tc in the profile, which we define as the end temperature (Te). We propose that Te would be better to define the completion point of starch Gelatinization than Tc.
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Molecular disassembly of starch granules during Gelatinization and its effect on starch digestibility: A review
Food and Function, 2013Co-Authors: Shujun Wang, Lesles CopelandAbstract:Starch is the most important glycemic carbohydrate in foods. The relationship between the rate and extent of starch digestion to produce glucose for absorption into the bloodstream and risk factors for diet-related diseases is of considerable nutritional interest. Native starch is attacked slowly by enzymes, but after hydrothermal processing its susceptibility to enzymatic breakdown is greatly increased. Most starch consumed by humans has undergone some form of processing or cooking, which causes native starch granules to gelatinize, followed by retrogradation on cooling. The extent of Gelatinization and retrogradation are major determinants of the susceptibility of starch to enzymatic digestion and its functional properties for food processing. The type and extent of changes that occur in starch as a result of Gelatinization, pasting and retrogradation are determined by the type of the starch, processing and storage conditions. A mechanistic understanding of the molecular disassembly of starch granules during Gelatinization is critical to explaining the effects of processing or cooking on starch digestibility. This review focuses on the molecular disassembly of starch granules during starch Gelatinization over a wide range of water levels, and its consequential effect on in vitro starch digestibility and in vivo glycemic index.
David S. Jackson - One of the best experts on this subject based on the ideXlab platform.
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Chapter 5 Starch Gelatinization
Advances in food and nutrition research, 2009Co-Authors: Wajira S Ratnayake, David S. JacksonAbstract:Abstract Starch occurs as highly organized structures, known as starch granules. Starch has unique thermal properties and functionality that have permitted its wide use in food products and industrial applications. When heated in water, starch undergoes a transition process, during which the granules break down into a mixture of polymers‐in‐solution, known as Gelatinization. The sequence of structural transformations that the starch granule undergoes during this order‐to‐disorder transition has been extensively researched. None of the published starch Gelatinization theories can fully and adequately explain the exact mechanism of sequential structural changes that starch granules undergo during Gelatinization. This chapter analyzes several published theories and summarizes our current understanding of the starch Gelatinization process.
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a new insight into the Gelatinization process of native starches
Carbohydrate Polymers, 2007Co-Authors: Wajira S Ratnayake, David S. JacksonAbstract:The Gelatinization characteristics of seven different food starches (regular corn, high-amylose corn, waxy corn, wheat, rice, potato, and tapioca) were investigated. Each starch sample type was heated to 35, 40, 45, etc. up to 85 °C at 5 °C intervals, and freeze-dried. The treated samples were analyzed using light microscopy, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and high-performance size exclusion chromatography (HPSEC). When heated, granules underwent structural changes prior to the visible morphological changes that took place during Gelatinization. The nature of these structural changes depended on starch type. These results indicate that the starch Gelatinization process is more complex than a simple granular order-to-disorder transition.
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Gelatinization and solubility of corn starch during heating in excess water new insights
Journal of Agricultural and Food Chemistry, 2006Co-Authors: Wajira S Ratnayake, David S. JacksonAbstract:Starch Gelatinization is associated with the disruption of granular structure causing starch molecules to disperse in water. This study was designed to examine starch granules as they were heated in water, and their resulting morphological, structural, and solubility traits. The results indicate that starch Gelatinization is a more complex process than the previously suggested order-to-disorder transition. The energy absorbed by the granules facilitates the rearrangement or formation of new bonds among molecules prior to the temperatures normally associated with the melting of amylopectin crystallites during Gelatinization. It is also evident that amylose plays an important role during the initial stages of corn starch Gelatinization. Keywords: Starch; Gelatinization
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Gelatinization and solubility of corn starch during heating in excess water: New insights
Journal of Agricultural and Food Chemistry, 2006Co-Authors: Wajira S Ratnayake, David S. JacksonAbstract:Starch Gelatinization is associated with the disruption of granular structure causing starch molecules to disperse in water. This study was designed to examine starch granules as they were heated in water, and their resulting morphological, structural, and solubility traits. The results indicate that starch Gelatinization is a more complex process than the previously suggested order-to-disorder transition. The energy absorbed by the granules facilitates the rearrangement or formation of new bonds among molecules prior to the temperatures normally associated with the melting of amylopectin crystallites during Gelatinization. It is also evident that amylose plays an important role during the initial stages of corn starch Gelatinization.