Degree Of Order Research Articles

Autoclaved Starch: Structure and Functionality Relationship in a Matrix With the Same Contribution ofAmylose and Amylopectin.

The rational use of autoclaved starches in food applications is difficult because there is a lack of information on their structure-functionality relationship. The novelty of this research relies on disclosing such an association. Hylon V starch was autoclaved at 105, 120, and 135°C to investigate its crystalline and double-helical features and its relationship with functionality. In autoclaved Hylon V starch, interactions of amylopectin and amylose improved while the crystalline regions decreased. The degree of double helices (DD) decreased after autoclaving at 105°C and the degree of order (DO) increased after treatment at 120 and 135°C. The water solubility index (WSI) (4.63-6.38%) and swelling power (SP) (4.39-7.1 g/g) increased when the temperature increased. On the other hand, water (103.49-225.01%) and oil (61.91-94.53%) holding capacity (WHC and OHC, respectively) increased after autoclaving treatment, although the values decreased with the treatment intensity. The functional properties were affected when the structure changed as a function of the treatment temperatures. PCA analysis showed that WSI and SP of autoclaved Hylon V starch were associated with a high DD, with better compaction, and with stronger amylopectin-amylose interactions. WHC and OHC were associated with better crystallinity, stronger interactions of amylopectin and amylose, and heterogeneous double-helical crystallites. These findings are useful for understanding the structure-functionality relationship of autoclaved Hylon V starch and pave the way for future research regarding the effects of its incorporation on the properties of food matrices such as bread, yogurt, cakes, and pudding.

Effects of Huangjing polysaccharides on the properties of sweet potato starch

Huangjing polysaccharides (HJP) have been shown to have many functions, however little was known about HJP on starch properties. This study investigated the effects of HJP from raw Huangjing (RHJP), high pressure steamed Huangjing (HPSHJP) and nine steamed and nine solarized Huangjing (NNHJP) on the properties of sweet potato starch (SPS). Results showed that HJP reduced setback viscosity (SB) of SPS. HJP decreased hardness, cohesiveness and chewiness, but increased the springiness of SPS gels. RHJP decreased tan δ of the starch gel but HPSHJP and NNHJP were less effective at higher frequencies. HJP increased the solubility but decreased the swelling power of SPS. Starch gel with HJPs showed a denser structure as observed by scanning electron microscopy. HJP decreased the relative crystallinity (RC) of the starch gel where HPSHJP was more effective than RHJP and NNHJP. HJP increased the degree of order (DO) while decreased the degree of double helix (DD) of SPS gels where RHJP was more effective than HPSHJP. Furthermore, HJP decreased the gelatinization enthalpy (ΔH) values of SPS with HPSHJP and NNHJP more effective. In conclusion, HJP could potentially improve the properties of SPS based foods but the changes of HJP after food processing require further investigation.

Changes in the properties of the corn starch glycerol film in a time-dependent manner during gelatinization

This study aimed to investigate the fundamental properties, solubility, mechanical properties, barrier performance, and microstructural features of films composed of corn starch and glycerol. Changes in the microstructure were analyzed to understand how they relate to the physical and chemical properties of these films. Specifically, we found that increasing the gelatinization time decreased the film thickness, solubility, water vapor permeability, and maximum degradation temperature and increased the water content. A gradual increase in the water contact angle of the corn starch–glycerol films was observed with increasing gelatinization time. This trend is likely due to the disruptive effect of gelatinization on the crystalline and amorphous structures inherent in corn starch, resulting in reduced film crystallinity, degree of order (DO) and degree of double helix (DD).

The Multiscale Structural Properties and In‐Vitro Digestibility of High Amylose Corn Starch During Autoclaving‐Cooling Treatment

AbstractThis work investigates the relationship between multiscale structural properties in high amylose corn starch (HACS) and its in‐vitro digestibility by analyzing the effects of autoclaving‐cooling treatment (ACT). Differential scanning calorimetry (DSC) shows that HACS displays a higher gelatinization temperature, wider endothermic gelatinization range, and higher enthalpy. Autoclaved corn starch exhibits enhanced thermal stability than the raw corn starch. X‐ray diffraction (XRD) shows that ACT does not change the crystalline type but increases the relative crystallinity (RC). Fourier transform infrared spectroscopy (FTIR) indicates that HACS exhibits a higher degree of order (DO) and double helixes (DHs) than normal corn starch (NCS), which are reduced by ACT. Scanning electron microscopy (SEM) reveals that HACS displays denser structures and smaller particle morphologies than NCS. After ACT, the granular of autoclaved corn starch shows a rough fiber network structure. Digestibility analysis reveals a positive correlation between the amylose content and resistant starch (RS) level in raw starch, while ACT promotes significant RS formation. This suggests that amylose promotes ordered structure formation, while autoclaving increased digestive resistance.

Structural changes of rice starch-anthocyanins complexes (V-type) and its impact on gut microbiotas and potential metabolic pathways during in vitro fermentation

This study explored the differences in the in vitro fermentation properties of rice starch (RS) and rice starch-anthocyanins complexes (RS-A). Structural characterization suggested that RS and RS-A complexes showed a V-type crystalline structure. The degree of order (DO) and degree of double helix (DD) values of RS and RS-A complexes were enhanced after fermentation. Moreover, the RS-A complexes could improve the relative abundance of Bacteroidetes, Ruminococcaceae, and up-regulate gut microbiota diversity to maintain gut homeostasis. Relative abundance of potential metabolic pathways, such as energy metabolism, digestion system, and carbohydrate degradation overexpressed in the presence of RS-A complexes. The results demonstrated that the RS-A complexes had slower fermentation rates contributing to the transport of the formed short-chain fatty acid (SCFA) to the end of the colon and that the crystallinity might be a factor influencing the utilization of the starch matrix by the gut microbiota for SCFA formation.

Red rice starch modification - Combination of the non-thermal method with a pulsed electric field (PEF) and enzymatic method using α-amylase

The objective of this study was to investigate the dual modification of red rice starch using pulsed electric field (PEF) and α-amylase, focusing on morpho-structural, thermal, and viscoamylographic properties. Native starch (Control) underwent various treatments: PEF at 30 kV cm−1 (PEF30), α-amylase at 9.0 U mg−1 (AA0), and a combination of both (PEF30 + α and α + PEF30). The PEF30 + α treatment exhibited the highest degree of digestion (10.66 %) and resulted in morphological changes in the starch granules, which became elongated and curved, with an increased average diameter of 50.49 μm compared to the control. The starch was classified as type A, with a maximum reduction in crystallinity of up to 21.17 % for PEF30. The deconvolution of FT-IR bands indicated an increase in the double helix degree (DDH) for PEF30 and AA0, while the degree of order (DO) was reduced for PEF30, AA0, and PEF30 + α. DSC analysis revealed significant modifications in gelatinization temperatures, particularly for PEF30, and these changes were supported by a reduction in gelatinization enthalpy (ΔH) of up to 28.05 % for AA0. These findings indicate that both individual and combined treatments promote a decrease in starch gelatinization and facilitate the process, requiring less energy. Differences were observed between the formulations subjected to single and alternating dual treatments, highlighting the influence of the order of PEF application on the structural characteristics of starch, especially when applied before the enzymatic treatment (PEF + α). Regarding the viscoamylographic parameters, it was observed that AA0 presented higher values than the control, indicating that α-amylase enhances the firmness of the paste. The double modification with PEF + α was more effective in reducing syneresis and starch retrogradation, leading to improvements in paste properties. This study provided significant insights into the modification of red rice starch using an efficient and environmentally friendly approach.

Effect of Calcium Hydroxide on Physicochemical and In Vitro Digestibility Properties of Tartary Buckwheat Starch-Rutin Complex Prepared by Pre-Gelatinization and Co-Gelatinization Methods

This study examined the effect of calcium hydroxide (Ca(OH)2, 0.6%, w/w) on structural, physicochemical and in vitro digestibility properties of the complexed system of Tartary buckwheat starch (TBS) and rutin (10%, w/w). The pre-gelatinization and co-gelatinization methods were also compared. SEM results showed that the presence of Ca(OH)2 promoted the connection and further strengthened the pore wall of the three-dimensional network structure of the gelatinized and retrograded TBS-rutin complex, indicating the complex possessed a more stable structure with the presence of Ca(OH)2, which were also confirmed by the results of textural analysis and TGA. Additionally, Ca(OH)2 reduced relative crystallinity (RC), degree of order (DO) and enthalpy, inhibiting their increase during storage, thereby retarding the regeneration of the TBS-rutin complex. A higher storage modulus (G') value was observed in the complexes when Ca(OH)2 was added. Results of in vitro digestion revealed that Ca(OH)2 retarded the hydrolysis of the complex, resulting in an increase in values in slow-digestible starch and resistant starch (RS). Compared with pre-gelatinization, the complex process prepared with the co-gelatinization method presented lower RC, DO, enthalpy, and higher RS. The present work indicates the potential beneficial effect of Ca(OH)2 during the preparation of starch-polyphenol complex and would be helpful to reveal the mechanism of Ca(OH)2 on improving the quality of rutin riched Tartary buckwheat products.

Performance of Liquid Crystalline Elastomers on Biological Cell Response: A Review

Dynamic interplay between extracellular matrix with anisotropic structure and biological cells has directed the scaffold path of development toward the utilization of actuation-responsive biomaterials. Among stimuli-responsive polymers, liquid crystalline elastomers (LCEs), owing to attachment of highly anisotropic mesogenic units to the amorphous elastomeric chains, are able to reveal reversible orientational order. Dynamic order–disorder phase transition and stimuli-responsiveness are the main factors to consider them as rationally smart mimickers of biological cell topology. This Review explains briefly the structures and synthesis methods of LCEs as well as their materiobiology with an emphasis on biochemical and biomechanical features of cells from molecular view. In this regard, some indispensable factors such as quasi-liquid crystalline behavior of cells, degree of orientational order in different cells and liquid crystalline induced topographical signals as growth enhancing agent for cells are investigated. Moreover, the interactions of cell-liquid crystalline substrate and the performance of LCE scaffolds on various cell lines response are given as an overview.

Correlation analysis on physicochemical and structural properties of sorghum starch.

This manuscript analyzed physicochemical and structural properties of 30 different types of sorghum starches based on their apparent amylose content (AAC). Current results confirmed that sorghum starch exhibited irregular spherical or polygonal granule shape with 14.5 μm average particle size. The AAC of sorghum starch ranged from 7.42 to 36.44% corresponding to relative crystallinities of 20.5 to 32.4%. The properties of enthalpy of gelatinization (ΔH), peak viscosity (PV), relative crystallinity (RC), degree of double helix (DD), degree of order (DO), and swelling power (SP) were negatively correlated with AAC, while the cool paste viscosity (CPV) and setback (SB) were positively correlated with AAC. Correlations analyzed was conducted on various physicochemical parameters. Using principal component analysis (PCA) with 20 variables, the difference between 30 different types of sorghum starch was displayed. Results of current study can be used to guide the selection and breeding of sorghum varieties and its application in food and non-food industries.

Universal flow-induced orientational ordering of colloidal rods in planar shear and extensional flows: Dilute and semidilute concentrations

The design of flow processes to build a macroscopic bulk material from rod-shaped colloidal particles has drawn considerable attention from researchers and engineers. Here, we systematically explore and show that the characteristic strain rate of the flow universally determines the orientational ordering of colloidal rods. We employed the fluctuating lattice Boltzmann method by simulating hydrodynamically interacting Brownian rods in a Newtonian liquid moving under various flow types. By modeling a rigid rod as a chain of nonoverlapping solid spheres with constraint forces and torque, we elucidate rigid rod dynamics with an aspect ratio (L/d) either 4.1 or 8.1 under various rotational Péclet number (Per) conditions. The dynamics of colloidal rods in dilute (nL3=0.05) and semidilute suspensions (nL3=1.1) were simulated for a wide range of Per (0.01<Per<1000) under shear flows including Couette and Poiseuille flows in a planar channel geometry, and an extensional and mixed-kinematics flow in a periodic four-roll mill geometry, where n is the number density, and d and L are the diameter and length of the rod, respectively. By evaluating the degree of orientational alignment of rods along the flows, we observed that there is no significant difference between flow types, and the flow-induced ordering of rods depends on the variation of Per up to moderate Per (Per<100). At a high Per (Per>100), the degree of orientational ordering is prone to diversify depending on the flow type. The spatial inhomogeneity of the strain-rate distribution leads to a substantial decrease in the orientational alignment at high Per.

Study of Changes in Crystallinity and Functional Properties of Modified Sago Starch (Metroxylon sp.) Using Physical and Chemical Treatment.

Sago starch has weaknesses such as low thermal stability and high syneresis. Modifications were made to improve the characteristics of native sago starch. In this study, sago starch was modified by autoclave-heating treatment (AHT), osmotic-pressure treatment (OPT), octenyl-succinic anhydride modification (OSA), and citric acid cross-linking (CA). This study aimed to examine the changes in chemical composition, crystallinity, and functional properties of the native sago starch after physical and chemical modifications. The results show that physical modification caused greater granule damage than chemical modification. All modification treatments did not alter the type of crystallinity but decreased the relative crystallinity of native starch. New functional groups were formed in chemically modified starches at a wavelength of 1700-1725 cm-1. The degree of order (DO) and degree of double helix (DD) of the modified starches were also not significantly different from the native sample, except for AHT and OPT, respectively. Physical modification decreased the swelling volume, while chemical modification increased its value and is inversely proportional to solubility. AHT and OPT starches have the best freeze-thaw stability among others, indicating that both starches have the potential to be applied in frozen food.

Size Segregation and Atomic Structural Coherence in Spontaneous Assemblies of Colloidal Cesium Lead Halide Nanocrystals

Colloidal nanocrystals (NCs) of fully inorganic lead halide perovskites (LHPs) are the latest generation of quantum-dot materials with compelling optical characteristics. Favored by the nearly regular cubic shape of NCs, they readily self-organize into highly ordered supercrystals (SCs) that have been stimulating in-depth investigation of uncommon collective properties at the fundamental level. Herein, we explore LHP NC SCs formed in colloidal suspensions and as solid materials, without any prior rigorous NC size-selection process. The spontaneous self-organization manifests itself in synchrotron wide-angle X-ray total scattering (WAXTS) measurements of randomly oriented ensembles of SCs by virtue of the substructure in the 100C peak (in cubic notation). By developing atomistic models of SCs, we find an evidence that, in spite of the initial NCs size polydispersity (up to 20%), SCs of CsPbBr3 and CsPbBr1.5I1.5 NCs form through a size segregation process. The SCs exhibit high spatial structural coherence, that is, crystallographic alignment between NCs, along two and three directions, a degree of orientational order (the SCs mosaicity) below 2°, and coherent sizes on the order of tens of nanometers. In situ coupled photoluminescence (PL) and WAXTS experiments evidence pronounced electronic coupling between NCs in SCs, seen as an ca. 50–70 meV red-shifted emission in dried samples compared to the corresponding dilute solution of NCs.

Magnetic properties of textured ferrocomposite consisting of immobilized superparamagnetic nanoparticles.

Wide use of magnetic nanoparticles in modern technologies and biomedical applications requires reliable theoretical models capable of predicting physical properties. Solidification of a ferroparticle suspension under the action of permanent magnetic field allows us to obtain a ferrocomposite, characterized by some orientational texture of the nanoparticle easy magnetization axes. The static magnetic response of this ferrocomposite differs from that of the parent magnetic suspension due to "freezing" of nanoparticle translational and rotational degrees of freedom. Here the superparamagnetic fluctuations of the nanoparticle magnetic moments play a key role in the formation of the ferrocomposite magnetic response depending on the degree of orientational ordering, obtained during synthesis of a ferrocomposite. With the help of statistical mechanics we calculate the magnetization and the initial magnetic susceptibility of the textured ferrocomposite for various temperatures and magnetic field strengths. The easy axis texturing leads to a significant increase of the magnetic properties, and the effect intensifies with the growth of nanoparticle magnetocrystalline anisotropy. Theoretical predictions are supported by Monte Carlo simulations. The obtained results evidence that the texturing of a ferroparticle suspension and transforming it into a textured ferrocomposite are a real way to enhance the magnetic response of these magnetic soft materials.

Controlling permeation in electrically deforming liquid crystal network films: A dynamical Landau theory.

Liquid crystal networks exploit the coupling between the responsivity of liquid crystalline mesogens, e.g., to electric fields, and the (visco)elastic properties of a polymer network. Because of this, these materials have been put forward for a wide array of applications, including responsive surfaces such as artificial skins and membranes. For such applications, the desired functional response must generally be realized under strict geometrical constraints, such as provided by supported thin films. To model such settings, we present a dynamical, spatially heterogeneous Landau-type theory for electrically actuated liquid crystal network films. We find that the response of the liquid crystal network permeates the film from top to bottom, and illustrate how this affects the timescale associated with macroscopic deformation. Finally, by linking our model parameters to experimental quantities, we suggest that the permeation rate can be controlled by varying the aspect ratio of the mesogens and their degree of orientational order when crosslinked into the polymer network, for which we predict a single optimum. Our results contribute specifically to the rational design of future applications involving transport or on-demand release of molecular cargo in liquid crystal network films.

Multiscale modelling of magnetostatic effects on magnetic nanoparticles with application to hyperthermia

We extend a renormalization group-based (RG) coarse-graining method for micromagnetic simulations to include properly scaled magnetostatic interactions. We apply the method in simulations of dynamic hysteresis loops at clinically relevant sweep rates and at 310 K of iron oxide nanoparticles (NPs) of the kind that have been used in preclinical studies of magnetic hyperthermia. The coarse-graining method, along with a time scaling involving sweep rate and Gilbert damping parameter, allow us to span length scales from the unit cell to NPs approximately 50 nm in diameter with reasonable simulation times. For both NPs and the nanorods composing them, we report effective uniaxial anisotropy strengths and saturation magnetizations, which differ from those of the bulk materials magnetite and maghemite of which they are made, on account of the combined non-trivial effects of temperature, inter-rod exchange, magnetostatic interactions and the degree of orientational order within the nanorod composites. The effective parameters allow treating the NPs as single macrospins, and we find for the test case of calculating loops for two aligned NPs that using the dipole approximation is sufficient for distances beyond 1.5 times the NP diameter. We also present a study on relating integration time step to micromagnetic cell size, finding that the optimal time step size scales approximately linearly with cell volume.

Structural changes in corn starch granules treated at different temperatures

The four structural levels of corn starch granules are as follows: particle structure, growth ring, crystalline region and chain structure. In this study, corn starch granules treated at different temperatures (50, 60, 70, 80, and 90 °C), then freeze-dried were evaluated. The corn starch granules remained largely intact in the control and at 50 °C and 60 °C, but with increasing temperature, the starch granules were broken. The growth ring structure and crystallization zone gradually broke up and disappeared with increasing temperature. Moreover, with increasing temperature, the degree of order (DO) and degree of the double helix (DD) of the crystalline region decreased gradually, indicating that the double helix structure of amylopectin in corn starch dissociated during heating. The molecular weight distribution index of corn starch was analyzed by gel permeation chromatography (GPC) and found that it increased with increasing temperature, indicating that the molecular chains of corn starch were broken during heating. In sum, the structural levels of corn starch granules, including the particle structure, growth ring, and crystalline region were damaged to varying degrees, whereas chain structure has been changed, after being processed at different temperatures. This study provides a model for theory of gelatinization in corn starch system.

An explicit and novel structure, lattice dynamics, and photoemission of La-doped nanocrystalline SrZrO3 perovskite

As no complete and comprehensive studies have been previously reported for La-doped nanocrystalline SrZrO3 (SZO), we researched herein a detailed investigation for pure and La-doped samples. A modified solid-state reaction process, including successive cycles of milling and sintering at high temperature, was followed to produce SZO and Sr0.9La0.1ZrO3 (SLZO) powdered ingots. Rietveld analysis of X-ray diffractometer data predicts that the two samples exhibit orthorhombic structure with an increase in crystallite size by ~25% for doped sample. A great reduction in Raman modes intensity (~60%) and an annihilation of several vibration modes were detected using Raman spectroscopy. The degree of ordering on the B-site was recorded to be higher in La-doped sample. According to ultraviolet–visible (UV–Vis) absorption, a decrease in the optical gap width (E g) from 4.40 eV to 4.21 eV was achieved by La incorporation due to the presence of additional defect states such as oxygen and Sr vacancies at the band edge. The process of electron–hole recombination was studied using photoluminescence (PL) spectroscopy. Deconvolution of PL spectra yielded four emission bands: one green band, one blue band, and two violet bands. Highly intense violet emission at λ = 393 nm approximately five times greater than that detected for pure SZO is realized as La3+ substitutes for Sr2+. Such property nominates SLZO for technological applications requiring highly intense violet emission, e.g., light-emitting diodes.

Resistant starch isolated from enzymatic, physical, and acid treated pea starch: Preparation, structural characteristics, and in vitro bile acid capacity

The multi-scale structural order and bile acid (BA) binding capacity of resistant starch (RS) isolated from native, different processed and recrystallized pea starch samples were studied. Different treatments applied include acid hydrolysis (AHPRS), pullulanase-debranching (PDPRS), autoclaving (ACPRS), ultrasound-autoclaving (UAPRS), and microwave cooking (MCPRS). Subsequently, the native, processed and recrystallized starch were subjected to in vitro digestion using thermostable α-amylase and amyloglucosidase to obtain the isolated RS. The Mw values of RS samples ranged from 2.448 × 104−9.750 × 106 g/mol, with the highest value noticed for ACPRS, and the lowest one for NPRS. The B-type and a small amount of V-type crystalline pattern was observed in all RS samples. Based on X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) measurement, the RS isolated from native pea starch, which is of type II resistant starch, exhibited the significantly lowest crystallinity and degree of order (DO), compared with RS3 samples prepared from processed and recrystallized starch. The relative crystallinities measured by 13CNMR (16.78–18.97%) were generally higher than the values of crystallinity obtained from XRD (3.36–12.23%). The strongest absorption that is related to O-H stretching between 3000 and 3600/cm on the FT-IR spectra, the highest DO value, and the highest BA binding capacity were observed for AHPRS.

Connectivity, Not Density, Dictates Percolation in Nematic Liquid Crystals of Slender Nanoparticles.

We show by means of continuum theory and simulations that geometric percolation in uniaxial nematics of hard slender particles is fundamentally different from that in isotropic dispersions. In the nematic, percolation depends only very weakly on the density and is, in essence, determined by a distance criterion that defines connectivity. This unexpected finding has its roots in the nontrivial coupling between the density and the degree of orientational order that dictate the mean number of particle contacts. Clusters in the nematic are much longer than wide, suggesting the use of nematics for nanocomposites with strongly anisotropic transport properties.

Structural characteristics and physicochemical properties of field pea starch modified by physical, enzymatic, and acid treatments

In order to meet industrial demands, field pea starch was modified by autoclaving (ACP), microwave cooking (MCP), and combined treatments of autoclaving with ultrasonication (UP), acid hydrolysis (AHP), or pullulanase debranching (PDP). The influence of different processing treatments on the structural and physicochemical characteristics of pea starch was investigated by X-ray diffraction (XRD), solid-state 13C nuclear magnetic resonance (13CNMR), Fourier transform infrared spectroscopy (FT-IR), small angle X-ray scattering (SAXS), differential scanning calorimeter (DSC), and scanning electron microscope. Processing of pea starch tended to decrease the long-range structural order with relatively lower values of crystallinity observed from XRD, whereas the double helical structure which is arranged at short range scale was enhanced to certain extents after different treatments. Microwave cooking was shown to be less effective than other treatments in promoting the formation of stabilized double helical structure, with the lowest values of crystallinity, degree of order (DO), double helix content, and gelatinization enthalpy obtained for MCP based on XRD, FT-IR, 13CNMR, and DSC observations. The experimental results also suggested that autoclaving had a less pronounced effect than the combined treatments of autoclaving-debranching, acid hydrolysis-autoclaving, and ultrasound-autoclaving on facilitating the formation of short-range ordered structure, with significantly lower values of DO, and double helix content obtained for ACP compared with AHP, PDP, and UP. This study was expected to provide a theoretical basis for the better understanding of the structure-processing-functionality relationship of starch polymers and to help the food industry to design novel starch materials with desirable functional properties.