Relative Crystallinity Research Articles

The Quality and Starch Digestibility of Multi-Grain Noodles Are Regulated by the Additive Amount of Dendrobium Officinale

Dendrobium officinale (DO) is a well-known medicinal and edible plant, yet its impact on the quality of noodles has been infrequently reported. In this study, DO was incorporated into multi-grain flour in varying proportions (0, 2, 4, 6, 8%) to prepare noodles, and their quality was assessed. The percentage increase in DO decreased the cooking loss, whiteness, appearance, and taste of the noodles while simultaneously enhancing their water absorption, adhesiveness, smoothness, and starch digestion resistance. Lower supplemental levels of DO (2–4%) facilitated the water absorption of protein and the formation of a dense and extensive protein network surrounding the partially gelatinized starch, which was characterized by higher relative crystallinity. The highest sensory score (77.4) and greatest content of slowly digestible starch content (38%) were observed in the noodles containing 4% DO. Conversely, higher percentages of DO (6–8%) diluted and compromised the protein network in the cooked noodles, leading to water migration from protein to starch. The excessive polysaccharides from DO tended to complex with fully gelatinized starch, promoting starch aggregation and interactions between starch and non-starch components. This ultimately resulted in the highest adhesiveness and resistant starch content (34%) in the cooked noodles with 8% DO. These findings provide a reference for enhancing noodle quality by regulating the amount of DO added, thereby promoting the application of DO in cereal-based food products.

Microwave coprocessing of modafinil with Gelucire®: Thermal and compression characteristics

Introduction: Modafinil, a wakefulness-promoting agent, is primarily used to treat excessive daytime sleepiness associated with narcolepsy and fatigue. As a BCS class II drug, modafinil exhibits low solubility and high permeability, with its crystalline structure significantly impacting dissolution, bioavailability, and compressibility. This study explores the use of microwave energy to alter the crystalline structure of modafinil in the presence of Gelucire® 48/16, aiming to improve its pharmaceutical properties. Methods: Modafinil was treated with microwave energy to form complexes with Gelucire® 48/16, and the resulting formulations were compared to hot-melt complexes and physical mixtures. The structural and thermal properties of the complexes were characterized using X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC), and Fourier-transform infrared spectroscopy. Compressibility and compactibility were evaluated through Kawakita model analysis and response surface methodolog). The effect of microwaves on molecular interactions was further investigated using molecular modeling. Results: XRPD analysis revealed distinct crystalline patterns for microwave and hot-melt complexes compared to physical mixtures, with increased amorphousness observed through crystallinity, relative crystallinity, and relative intensity parameters. DSC thermograms indicated a reduction in melting endotherms and heat flow, suggesting structural changes due to complex formation. Compressibility and compactibility studies demonstrated optimal performance at low Gelucire® content, with microwave-treated complexes exhibiting superior properties to untreated mixtures. Molecular modeling confirmed dipole-dipole interactions between modafinil and the hydrophilic portion of Gelucire®. Conclusions: The study demonstrates that microwave energy effectively alters the crystalline structure of modafinil in the presence of Gelucire® 48/16, enhancing its amorphousness, compressibility, and compactibility. These findings highlight the potential of microwave-assisted complexation as a novel approach to improve the pharmaceutical performance of BCS Class II drugs like modafinil.

Structural alterations in butyrylated and recrystallized high-amylose maize starch and their effect on gut microbiota during in vitro fermentation.

In this study, type-3 resistant starch (RS) with enhanced thermal stability and excellent short-chain fatty acid (SCFA) production was obtained through the butyrylation and subsequent recrystallization at 4 °C of high-amylose maize starch (HAMS). We comprehensively examined and contrasted the structural attributes and in vitro human fecal fermentation behavior of butyrylated RS (BRS) with varying degrees of substitution. Fourier-transform infrared analysis validated the successful integration of carbonyl groups into the starch matrix. This phenomenon was evident through the characteristic peaks at 1727 cm-1. X-ray diffraction and thermal stability analyses delineated the distinct B-type crystalline structure and high relative crystallinity of 25.31 % and 22.23 % of the 10 % and 15 % butyric anhydride BRS-10 and BRS-15, respectively, which differed from that of HAMS. Their second peak gelatinization temperature values reached 95.6 °C and 92.6 °C. The in vitro fermentation of BRS fostered SCFA production, boosting the relative abundance of beneficial bacteria (e.g., Ligilactobacillus and Roseburia). Meanwhile, the extensively modified BRS favored the propagation of Faecalibacterium and Bifidobacterium, maintaining intestinal microbiota advantage. These findings underscore the significant effects of butyrylation modification on fermentation kinetics, metabolite profiles, and gut microbiota composition, providing invaluable insights into the development of functional food products that aim to bolster colonic health.

Impact of Ultrasonic-Assisted Preparation of Water Caltrop Starch-Lipid Complex: Structural and Physicochemical Properties.

This study investigates the effect of ultrasonic-assisted preparation on the structural and physicochemical properties of water caltrop starch-palmitic acid complexes as a function of ultrasound intensity and treatment time. All samples exhibited the characteristic birefringence of starch-lipid complexes under the polarized microscope, and flake-like and irregular structure under scanning electron microscope (SEM), indicating the formation of complexes through ultrasonic-assisted preparation. X-ray diffraction pattern further confirmed the transition from the original A-type structure for native starch to V-type structure for starch-lipid complexes, and the relative crystallinity of starch-lipid complexes increased as the ultrasound intensity and treatment time increased. Attenuated total reflectance-Fourier-transform infrared spectroscopy (ATR-FTIR) analysis indicated a decreasing trend in absorbance ratio at wavenumber of 1022 cm-1/995 cm-1, suggesting that the increase in the complex promoted the self-assembly within the short-range ordered structure, leading to the formation of bonds between the complexes. However, rapid-visco analysis (RVA) demonstrated that the viscosity generally decreased as the ultrasound intensity and treatment time increased, possibly due to the reduction in molecular weight by ultrasound. Differential scanning calorimetric (DSC) analysis revealed that the control starch-lipid complex without ultrasound treatment (US-0-0) exhibited two distinct endothermic peaks above 90 °C, representing Type I (95-105 °C) and Type II (110-120 °C) V-type complexes. However, ultrasound-treated samples showed only one peak around 95-105 °C and increased enthalpy (∆H), which was likely due to the breakdown of amylose and amylopectin, leading to more complex formation with palmitic acid, while the resulting shorter chains in the ultrasound-modified sample favor the formation of Type I complexes.

Characterization and Comparison of Structure and Physicochemical Properties of Highland Barley Starch of Different Colors.

Domesticated highland barley is an important starch reserve and has differently colored grains, owing to different genotype backgrounds and cultivation environments. In this study, black, purple, blue, and yellow highland barley varieties were planted under the same cultivation conditions, and their starch distribution, structural characteristics, and physicochemical properties were analyzed. The apparent amylose content was highest in the purple variety (20.26%) and lowest in the yellow variety (18.58%). The different varieties had three subgroups and A-type crystalline structures, but the particle size and relative crystallinity (25.67-27.59%) were significantly different. In addition, the weight average molecular weight (6.72 × 107 g/mol), area ratio of APs to APL (2.88), relative crystallinity (27.59%), and 1045/1022 (0.730 cm-1) of starch were higher in yellow highland barley (YHB), forming a stable particle structure and increasing the Tp and PV of its starch. A cluster heat map showed that starches from differently colored highland barley vary in fine structure, water solubility, swelling power, and thermal and pasting properties. This study provides a reference for the high-quality breeding of colored highland barley and its utilization in food and non-food industries.

Combining Controlled-Release and Normal Urea Enhances Rice Grain Quality and Starch Properties by Improving Carbohydrate Supply and Grain Filling.

Controlled-release nitrogen fertilizers are gaining popularity in rice (Oryza stavia L.) cultivation for their ability to increase yields while reducing environmental impact. Grain filling is essential for both the yield and quality of rice. However, the impact of controlled-release nitrogen fertilizer on grain-filling characteristics, as well as the relationship between these characteristics and rice quality, remains unclear. This study aimed to identify key grain-filling characteristics influencing rice milling quality, appearance, cooking and eating qualities, and physicochemical properties of starch. In this study, a two-year field experiment was conducted that included four nitrogen management practices: zero nitrogen input (CK), a local high-yield practice with split urea applications (100% urea, CU), a single basal application of 100% controlled-release nitrogen fertilizer (CRNF), and a basal application blend of 70% controlled-release nitrogen fertilizer with 30% urea (CRNF-CU). The results showed that a sufficient amount of carbohydrates for the rice grain-filling process, as indicated by a higher sugar-spikelet ratio, is essential for improving grain quality. An increased sugar-spikelet ratio enhances the grain-filling process, resulting in an elevated average grain-filling rate (Gmean) and the peak grain-filling rate (Gmax), while also reducing the overall time required for grain filling (D). Compared to CU, CRNF and CRNF-CU treatments did not significantly change milling qualities, but reduced the chalky kernel rate and chalkiness, thereby enhancing the appearance quality. These treatments increased the amylose and amylopectin contents while reducing protein content, though the proportion of protein constituents remained unchanged. These treatments led to larger starch granules with notably smoother surfaces. Additionally, CRNF and CRNF-CU reduced relative crystallinity and structural order, while increasing the amorphous structure in the outer region of starch granules, which lowered rice starch crystal stability. The treatments also increased viscosity and improved the thermodynamic properties of starch, resulting in enhanced eating and cooking quality of the rice. In conclusion, the CRNF-CU is the most effective strategy in this study to enhance both grain yield and quality. This practice ensures an adequate carbohydrate supply for grain filling, which is essential for efficient grain filling and improved overall quality.

Investigating the influence of the molecular structure and physiochemical properties of starches from glutinous and japonica sorghum on light-flavor liquor fermentation.

Glutinous and japonica sorghum can be applied to different production processes by their amylopectin content and starch structure. However, the differences in the fine structure and physiochemistry properties of their starches, as well as their fermentation properties remain unclear. Compared with japonica sorghum, glutinous sorghum has a higher amylopectin content, short amylose chain content, relative crystallinity, and ∆Hgel, but lower setback (SB), and starch granule size. Correlation analysis showed that the amylose content was positively correlated with the SB and final viscosity (FV) and negatively correlated with the relative crystallinity (RC), peak pasting temperature, and ∆Hgel. The short amylose content was positively correlated with RC and onset pasting temperature; and the starch granule size was positively correlated with the FV, SB, SR, and pasting time. Principal component analysis indicated that the glutinous and japonica sorghum varieties could be separated by PC1. Fermentation experiments revealed that glutinous sorghum had a higher liquor yield than japonica sorghum, the LN18 and LN22 had the highest starch utilization, and the YHN4 had the highest liquor yield. Our findings provide a theoretical basis for the development of new sorghum varieties for brewing and fermentation control, and they can assist enterprises in screening high-quality raw materials for use in the Baijiu brewing industry.

Effect of dynamic high pressure microfluidization on pasting, gelling and rheological properties of starch composite with β-glucan both from highland barley.

The objective of this study was to investigate the effect of β-glucan on the pasting, gelling, rheological properties, and multi-level structures of the highland barley (HB) starch after dynamic high pressure microfluidization (DHPM) treatment, exploring the inhibition mechanisms of starch retrogradation by endogenous β-glucan after DHPM. DHPM treatment led to a decrease in the viscosity (K values from 161.1 to 54.4) of HB starch-β-glucan composite as the pressure increased from 0 to 120 MPa, while an increase in the viscosity was induced by DHPM treatment cycles from 1 to 3 at 120 MPa. Similar changes were also found in the relative crystallinity (RC) and degree of retrogradation (DR). The RC values decreased from 44.66 % to 25.53 %, and the DR values decreased from 53.4 % to 24.6 % as the DHPM pressure increased from 0 MPa to 120 MPa (p < 0.05). However, when number of DHPM cycles increased from 1 to 3 under 120 MPa, the RC value and DR value increased to 35.99 % and 31.9 %, respectively. Scanning electron microscopy images demonstrated that β-glucan formed a protective layer around HB starch granules after DHPM treatment at 120 MPa for one pass. Fourier transform infrared spectra and X-ray diffraction results indicated the intra- and intermolecular hydrogen bonds between HB starch and β-glucan were strengthened by DHPM. Endogenous β-glucan emerged as a strong candidate for inhibition of HB starch retrogradation. This study highlights an innovative and promising strategy for improving the properties of HB starch and facilitating its utilization.

New insights into influencing the extraction efficiency of tigernut oil: Impact of heat on oil absorption and enzymatic hydrolysis of tigernut starch in a starch-protein-oil model system.

Tigernut is a potential source of valuable edible oil; however, current oil extraction techniques are inefficient. We assessed high temperature-induced variations in oil absorption and enzymatic hydrolysis of tigernut starch (TS) in the presence of protein to explore the intrinsic reasons for the low oil extraction from tigernut. The results showed that, due to high temperature and the presence of protein, an increase in the volume mean diameters and agglomeration of TS granules occurred. As the temperature increased (80-140°C), the relative crystallinity (19.09%-24.40%) of the long-range ordered structure and the orderliness of the short-range ordered structure increased, the total oil absorption (TOA: 0.25-0.19g oil/g sample) decreased, and the starch-lipid complex index (2.56%-24.61%) increased. With increasing temperature in the range of 170-200°C, the short-range ordered structure of TS became more compact, and the TOA (0.18-0.14g oil/g sample) and the starch-lipid complex index (24.61%-5.64%) decreased. Changes in the structure of TS led to an increase and then a decrease in its thermal stability, an enhancement of the gel network structure, and a weakening of enzymatic hydrolysis. Results can help reveal the oil absorption mechanism of TS and regulate its physicochemical properties for the efficient extraction of tigernut oil.

Effects of soy protein isolate hydrolysate on the structural and functional properties of yam starch during extrusion.

This study investigated the interaction between yam starch (YS) and soy protein isolate hydrolysate (SPH), and their effects on in vitro digestibility of starch through extrusion treatment. Results indicated that SPH with 6% hydrolysis degree had the lowest relative molecular mass. X-ray diffraction and Raman spectroscopy revealed an increase in the relative crystallinity of extruded yam starch (EYS) from 17.45% to 22.45% and a decrease in the half-peak width at 480cm-1. Its short-range ordering improved with increased SPH addition. Differential scanning calorimetry results demonstrated that SPH enhanced the thermal properties of EYS. Additionally, the solubility, peak viscosity, and setback viscosity of EYS decreased with an increase in the SPH content. Particle size analysis revealed that SPH addition decreased the particle size of EYS. Scanning electron microscopy and confocal laser scanning microscopy showed that the surface of EYS roughened and SPH molecules attached to the surface. In vitro digestion results indicated that SPH hindered the contact between EYS molecules and digestive enzymes and increased the resistant starch content of EYS from 8.31% to 23.39%. This study presents a new method for modification of starch using protein hydrolysates during extrusion.

Effects of extrusion temperature on structure and physicochemical properties of proso millet starch.

Due to its thermal stability, and high viscosity, proso millet starch has limited practical applications. Extrusion can alter the functional properties of starch by pre-gelatinization, but the specific effects of extrusion temperature on starch behavior are not clear. In this study, proso millet starch was modified using extrusion at varying temperatures (70°C, 90°C, 110°C), and its structure as well as physicochemical properties were evaluated. As the extrusion temperature increased, the starch granules were gelatinized, and the particle size increased significantly. The relative crystallinity of extruded starch decreased and the short-range order was enhanced notably, but the starch still exhibited an A-type structure. Starch chains degraded, migrated, and aggregated, showing an increase in the double helix content, but there was no difference in the single helix structure with temperature. With the increase of extrusion temperature, the amorphous layer of extruded starch thickened. Moreover, the peak viscosity, breakdown viscosity and setback viscosity initially increased and then decreased, the peak temperature and enthalpy change increased. The water absorption index, water solubility and swelling power significantly decreased with increasing temperatures. The freeze-thaw stability and transparency of extruded starch decreased, and showed a downward trend with prolonged time. The above results indicate that extrusion treatment effectively modifies the thermal stability and viscosity of proso millet starch, laying a foundation for applying it different industrial applications.

Properties of New Partially Crystallized Lithium Disilicate CAD-CAM Materials.

The purpose of this study was to compare the optical, mechanical, and biological properties of two new, inexpensive lithium disilicate (LS2) materials (Lodden (LOD), LD Medical Technology; and BeautyZir (BZ), BeautyZir Technology) to a clinically established LS2 material (IPS e.max CAD (EMAX), Ivoclar Vivadent). The optical properties of the translucency parameter (TP) and opalescence parameter (OP) were obtained with a dental spectrophotometer. The mechanical properties of flexural strength (FS) and flexural modulus (FM) were determined through a three-point bend test conducted using a universal testing machine. Biocompatibility tests were conducted by analyzing cell proliferation using spectrophotometric absorbance (optical density) to determine relative growth rate and cytotoxicity. Representative specimens of the three LS2 materials were analyzed with X-ray diffraction to determine the relative crystalline phases. Data were analyzed with oneway ANOVA and Tukey's post hoc test (α=0.05). Significant differences in optical and mechanical properties were found amongst the groups (p<0.05). Both LOD and BZ had significantly greater TP and OP compared to EMAX. EMAX and LOD had greater FS and FM than BZ. No significant differences in optical density or relative growth rate were found among any of the LS2 groups (p>0.05). EMAX and LOD had greater weight percent of lithium disilicate than BZ. The new lithium disilicate LS2 material, LOD, exhibited better optical properties while maintaining mechanical and biological properties similar to the established LS2 material, EMAX.

Understanding the role of Radix Paeoniae Alba polysaccharide for corn starch gel amelioration: Physicochemical, structural, and digestive properties.

To ameliorate the limitations of corn starch (CS) processing, Radix Paeoniae Alba polysaccharide (RPAP) was used to modulate the physicochemical and digestive properties of CS. The main purpose of this paper is to investigate the effects of RPAP on the pasting, rheological, thermal, structural, and digestive properties of CS. The results show that the addition of RPAP could increase the peak viscosity and final viscosity of CS gel, and RPAP could increase the apparent viscosity, storage modulus, loss modulus, hardness, and strength of CS gel, implying that RPAP can effectively improve the pasting and viscoelasticity properties of CS. Moreover, RPAP could be bound to CS through non-covalent interaction, and RPAP could improve the relative crystallinity and thermal stability, whereas decreased the spin relaxation time (T2) of CS from 312.16 to 203.25 ms. The microstructure of CS-RPAP gels showed a honeycomb-like porous structure, and RPAP could increase the pore size and thickness of CS-RPAP gels. Furthermore, RPAP could inhibit the digestibility of CS, while increased the resistant starch (RS) content. The findings can provide important references for expanding the application of starch-based products in various fields including food industry, pharmaceuticals, textiles, papermaking, and biodegradable materials.

Study on the Aging Effects of Relative Humidity on the Primary Chemical Components of Palm Leaf Manuscripts.

Palm Leaf Manuscripts represent a significant component of the world's cultural heritage. Investigating their primary chemical components and understanding the transformations these materials undergo under environmental influences are crucial for elucidating their material characteristics and aging mechanisms and developing effective strategies for preventive conservation. This study utilized infrared absorption spectroscopy and X-ray diffraction analysis to examine changes in the primary chemical components of Palm Leaf Manuscripts under varying relative humidity conditions over extended periods. The findings reveal that dry environments lead to surface cracking, while humid environments promote mold growth, both of which contribute to the degradation of the primary chemical components. These degradative processes reduce cellulose crystallinity and thermal stability. The deterioration is particularly severe under high humidity, with hemicellulose degrading faster and more extensively than cellulose under the same conditions. After 200 days of aging at 10% RH and 90% RH, cellulose degradation reached 19.82% and 54.40%, respectively, while hemicellulose degradation was 34.78% and 64.28%. Correspondingly, the relative crystallinity of cellulose decreased by 8.01% and 13.11%. In contrast, samples maintained at 50% RH exhibited minimal deterioration, with cellulose and hemicellulose degrading by only 4.08% and 13.55%, respectively, and a 6.61% reduction in cellulose crystallinity. These results suggest that a relative humidity of 50% is optimal for the preservation of Palm Leaf Manuscripts. This study offers significant insights into the ageing mechanisms and preventive conservation of Palm Leaf Manuscripts, as well as other cellulose-based organic heritage materials.

Effects of air flow micro pulverized wheat bran dietary fiber on physicochemical, structural, and digestive properties of wheat starch.

The effects of wheat bran dietary fiber (WBDF) treated by air flow micro-pulverization on gelatinization, thermal, rheological, structural properties, and in vitro digestion of wheat starch (WS) were investigated. Different particle sizes of WBDF were obtained by conventional knife grinding and airflow micro-grinding. Compared with conventional knife grinding, the particle size of WBDF treated by air flow micro-pulverization decreased, the particle size distribution was concentrated at small particle sizes, the specific surface area increased, and the hydraulic and oil-holding power decreased, which was mainly related to the change of WBDF spatial structure and the increase of solubility. At the same time, the peak viscosity, setback, breakdown, and resistant starch content short-range order degree and relative crystallinity of WS were increased by adding WBDF treated by air flow micro-pulverization, whereas the gelatinization enthalpy value and apparent viscosity were decreased. This indicated that the air micro pulverized WBDF promoted gelatinization and inhibited digestion while reducing the thermal stability of WS, leading to short-term recovery. This study provides a theoretical reference for the production and processing of gluten-containing flour products. PRACTICAL APPLICATION: In this study, the physical and chemical properties and spatial structure of air flow micro pulverized dietary fiber of wheat bran were analyzed, and its effects on the properties of wheat starch were studied. Therefore, this study provides a theoretical basis for the industrial application of gluten-containing flour products.

Preparation and characterization of nanoparticle and nanocrystal from sago starch

There is an emerging interest in the development of starch-biomaterial for various applications such as in food emulsions. Starch has several advantages to be modified as they are low-cost material, submicron in size with a high surface area to volume ratio and abundance of functional groups for surface modifications. The objective of this study was to prepare and investigate the morphological, structural and physicochemical properties of nanoparticles (SNP) and nanocrystals (SNC) extracted from sago starch. SNP was prepared by enzymatic hydrolysis with 5% pullulanase at 58°C for 24 hrs, meanwhile SNC was produced by acid hydrolysis with aqueous sulphuric acid (H2SO4) for 5 days at 40°C. Both SNP and SNC showed a size lower than 1000 nm and a homogenous polydispersity index. The X-ray diffraction analysis showed that the relative crystallinity increased significantly (p&lt;0.05) and allowed stronger hydrogen bond interaction in both SNP and SNC. Besides that, swelling power, solubility and yield of SNP were significantly higher (p&lt;0.05) than SNC as it was greatly influenced by the amorphous and crystalline regions of the starch particles after hydrolysis. Moreover, SNP have a less distinct shape with a size larger than SNC favoured by self-aggregation and lower zeta potential value. Overall, SNP prepared by enzymatic hydrolysis showed the most promising materials to meet industrial demands due to the environmental friendliness (no pollution), high yield and less preparation time needed. Therefore, the newly fabricated SNP have potential as an emulsifier, encapsulating agents and others regardless of any food system.

Phase-field modeling of the morphological and thermal evolution of additively manufactured polylactic acid layers and their influence on the effective elastic mechanical properties

AbstractThis study presents a comprehensive simulation of the fused deposition modeling (FFF) process of polylactic acid (PLA) using the multiphase-field method. Compared to existing works, this work aims to simulate the overall FFF process. It combines temperature evolution, viscous flow, polymer crystallization, and residual strain calculations within the microstructure with mechanical property analysis in a single study. Simulation studies were done in the case of the single layer to study the flowing effect of the filament and the distribution of temperature, viscosity, and relative crystallinity throughout the cooling process. Afterward, a system of layers with three rows and three columns was investigated. The nozzle temperature, bed temperature, viscosity, and layer height were varied, and for each case the porosity was calculated. After running mechanical loading simulations on each case, the effective Young’s modulus was calculated. The simulations show that increasing the nozzle and bed temperatures leads to a decrease in the porosity, while increasing the layer height increases the distortion in the pores’ shapes without significantly affecting the porosity. The decrease in porosity leads to an increase in the effective Young’s modulus of the structure in a linear trend within the investigated porosities. The Young’s modulus–porosity relation was validated with experimental values from the literature within an average error of 3.6 %.

Structural and Property Changes in Corn Starch Straws via NCU‐017 Strain Fermentation

ABSTRACTThis study utilizes corn starch fermented by the NCU‐017 strain to prepare straws and investigates the effects of NCU‐017 strain fermentation on the structure and functional properties of the starch straws. The results show that the fermented starch straws exhibit a decrease in number‐average molecular weight (Mn) and amylose content compared to the non‐fermented control straws (CS), while the proportion of starch chains with DP 6–12 increases. Fermentation reduces starch straws' hydrogen bond strength and gelatinization enthalpy (ΔH). X‐ray diffraction (XRD) reveals that fermentation does not alter the crystal type of starch straws, but increases the relative crystallinity from 13.19% to 15.38%. The fermented starch straws are more water‐resistant than CS, and they do not bend after being soaked in water at 4 and 25°C for 1 h. This is due to the formation of a dense structure which can be observed from the scanning electron microscope (SEM). Fermentation significantly reduces the starch straws' maximum bending force (Fb) but increases their bending modulus of elasticity (Eb). This study demonstrates the potential application of bacterial fermentation in improving the functional properties of starch straws.

Synthesis of Hollow Zn/ZSM-5 Nanosheets via Different Alkali Treatments with ZIF-8 as a Zn Source for Efficient Aromatization of Methanol.

Diffusion limitations and monofunctional acidity of ZSM-5 molecular sieves affect the catalyst stability and aromatic yield in the reaction of methanol to aromatics (MTA). In this study, based on ZSM-5 nanosheets as parent molecular sieves, Zn-modified hollow ZSM-5 nanosheets were obtained after hydrothermal treatment by adding ZIF-8 or zinc nitrate as a source of Zn while treating with different types and concentrations of alkali solutions. The physical and chemical properties of the fabricated samples and their catalytic performance of methanol aromatization were systematically investigated by a combination of XRD, TEM, N2 adsorption-desorption, NH3-TPD, Py-IR, 27Al MAS NMR, 29Si MAS NMR, XPS, and TG characterization analyses and MTA experimental evaluation. The results indicated that a hollow structure emerged in the samples after alkaline treatment, with a significant increase in the proportion of mesopores, which further increased with the concentration of the alkaline solution. Both alkaline treatment and the introduction of Zn led to changes in the acidity of the catalyst. The increase in tetrahedrally coordinated aluminum during the alkaline treatment resulted in a higher content of B acid sites, while the introduction of Zn formed Zn-Lewis acid sites. Among the prepared samples, the catalyst obtained using ZIF-8 as the Zn source and treated with a mixed alkaline solution of 0.15 M sodium hydroxide and tetrapropylammonium hydroxide (ZnZ8(N+T)/Z5) exhibited higher relative crystallinity, more appropriate micromesopore ratio, a greater amount of Zn(OH)+, and a suitable B/L ratio (0.74). Under the same conditions (450 °C, atmospheric pressure, weight hourly space velocity (WHSV) = 5 h-1), the aromatic product yield of ZnZ8(N+T)/Z5 reached 26.2%, which is 14 percentage points higher than that of the parent ZSM-5 and 4 percentage points higher than that of ZnZN(N+T)/Z5 modified with zinc nitrate as the Zn source. After 8 h of reaction, the aromatic yield over ZnZ8(N+T)/Z5 could still be maintained above 18.5% with good catalyst stability.

Debranched Lentil Starch-Sodium Alginate-Based Encapsulated Particles of Lacticaseibacillus rhamnosus GG: Morphology, Structural Characterization, In Vitro Release Behavior, and Storage Stability.

Starches with different degrees of debranching (DBS30, DBS60, and DBS90) and sodium alginate were used as the wall material for encapsulating particles of Lacticaseibacillus rhamnosus GG (LGG). The structural characteristics of these encapsulated particles were examined, along with the impact of varying levels of debranching on the encapsulation efficiency, the in vitro release of LGG under the simulated gastrointestinal environment, and the storage stability of the encapsulated particles. The results revealed a transformation in the crystalline polymorph from C- to B+V-type following debranching and retrogradation. This process also resulted in a significant decrease in molecular weight and polydispersity index, accompanied by an increase in amylose and resistant starch levels along with the relative crystallinity of the debranched lentil starch. Comparatively, DBS60-LGG and DBS90-LGG exhibited higher encapsulation efficiency and encapsulation yield than UDBS-LGG and DBS30-LGG. Furthermore, these encapsulated particles provided enhanced protection for LGG in both the simulated gastrointestinal environment and the storage process. It can be inferred that a superior encapsulation performance of the debranched lentil starch-sodium alginate-based encapsulated LGG particles was associated with higher debranching levels, a more uniform molecular weight distribution, and a more ordered multi-scale structure of the debranched lentil starch.