Structure Of Starch Research Articles

Structural changes of wheat starch and activity inhibition of α-glucosidase by persimmon (Diospyros kaki Thunb.) leaves extract retarding starch digestibility

Elevated blood sugar levels caused by starch digestion was a target for controlling diabetes mellitus. The in vitro and in vivo digestibility of wheat starch was evaluated to find that adding 15 % persimmon leaf extract (PLE) to starch reduced its digestibility by 69.50 % and the peak postprandial blood glucose by 23.63 %. Subsequently, we observed under scanning electron microscopy and atomic force microscopy that the presence of PLE led to the destruction of starch structure and the aggregation of α-glucosidase so as to decrease starch digestion and hinder the binding of starch to α-glucosidase. Through multi-spectral analysis, PLE hindered the clathrate of iodine and starch, and also increased the crystallinity of starch by 48.58 %. For α-glucosidase inhibitory activity (IC50 = 72.49 μg/mL), PLE preferentially occupied the active center of α-glucosidase, changed its fluorescence characteristics and secondary structure through hydrogen bonding and hydrophobic interaction. Moreover, among the 23 potential α-glucosidase inhibitors screened from PLE, combined with molecular simulation, Procyanidin B2 had the strongest inhibitory effect (IC50 = 33.22 μg/mL) and binding energy (−7.09 kcal/mol), which was most effectively inhibitory on digestion. These results indicated the potential of PLE in hypoglycemia targeting both starch and α-glucosidase.

Recent Advances in Physical Processing Techniques to Enhance the Resistant Starch Content in Foods: A Review.

The physical modification of starch to produce resistant starch (RS) is a viable strategy for the glycemic index (GI) lowering of foods and functionality improvement in starchy food products. RS cannot be digested in the small intestine but can be fermented in the colon to produce short-chain fatty acids rather than being broken down by human digestive enzymes into glucose. This provides major health advantages, like better blood sugar regulation, weight control, and a lower chance of chronic illnesses. This article provides a concise review of the recent developments in physical starch modification techniques, including annealing, extrusion, high-pressure processing, radiation, and heat-moisture treatment. Specifically, the focus of this paper is on the alteration of the crystalline structure of starch caused by the heat-moisture treatment and annealing and its impact on the resistance of starch to enzymatic hydrolysis, as well as the granular structure and molecular arrangement of starch caused by extrusion and high-pressure processing, and the depolymerization and crosslinking that results from radiation. The impacts of these alterations on starch's textural qualities, stability, and shelf life are also examined. This review demonstrates how physically modified resistant starch can be used as a flexible food ingredient with both functional and health benefits. These methods are economically and ecologically sustainable since they successfully raise the RS content and improve its functional characteristics without the need for chemical reagents. The thorough analysis of these methods and how they affect the structural characteristics and health advantages of RS emphasizes the material's potential as an essential component in the creation of functional foods that satisfy contemporary dietary and health requirements.

Aging time improves adhesive performance of handmade starch paste for restoration of ancient Chinese books and its mechanism of action

In the restoration of ancient Chinese books, handmade starch paste serves as a paper adhesive, distinguished from traditional starch paste preparation methods. It involves special processes such as starch washing and aging, relying entirely on the artisanal expertise throughout the entire process. The study recreates the process of making handmade starch paste for the restoration of traditional ancient books and investigates the effects of aging time on the apparent viscosity, rheological properties, and adhesive performance of the paste. The results indicate that during aging, the pH of the starch paste decreases significantly, but it has a minimal impact on its apparent viscosity, rheological properties, and paper softness. However, it notably enhances the adhesive performance, with the optimal results observed after 3 days of aging. This is attributed to the decrease in residual protein content in the starch, as well as the significant improvement in swelling power and solubility of the starch. The results of infrared spectroscopy and XRD testing reveal that there are no significant changes in the molecular and crystalline structures of starch during the aging process. The acidic environment produced by starch fermentation promotes protein hydrolysis, emerging as the primary reason for the improved adhesive performance of the paste.

Enhancing cassava beer quality: Extrusion-induced modification of cassava starch structure boosts fermentable sugar content in wort

The high starch content and cost-effectiveness of cassava make it an attractive adjunct in beer brewing, with the fine structure of starch playing a crucial role in determining the composition of fermentable sugars (FS) and overall beer quality. This study investigated the effect of extrusion-induced changes in the starch structure of cassava flour on the FS profile of the wort and, consequently, on the quality attributes of cassava beer. The findings revealed that the shear stress during extrusion significantly reduced the molecular weight to 1.20 × 105g/mol and the branching degree of amylopectin. Simultaneously, there was an increase in the concentrations of short- and intermediate- chain amylose by 5.61% and 42.72%, respectively. These structural changes enhanced the enzymatic hydrolysis of extruded cassava flour (ECF), resulting in a higher total fermentable sugars content (22.00g/100 mL) in the ECF wort, predominantly composed of maltose and glucose. Furthermore, the altered FS profile led to an increased production of higher alcohols and esters in extruded cassava beer (ECB), particularly noted for the elevation of 2-phenylethyl alcohol levels, which imparted a distinctive rose aroma to the ECB. Consequently, the sensory profile of ECB showed significant improvement. This study offers critical insight into optimizing cassava beer quality and broadens the potential applications of cassava flour in the brewing industry.

Insights into impact of chlorogenic acid on multi-scale structure and digestive properties of lotus seed starch under autoclaving treatment

The interaction between polyphenols and starch is an important factor affecting the structure and function of starch. Here, the impact of chlorogenic acid on the multi-scale structure and digestive properties of lotus seed starch under autoclaving treatment were evaluated in this study. The results showed that lotus seed starch granules were destroyed under autoclaving treatment, and chlorogenic acid promoted the formation of loose gel structure of lotus seed starch. In particular, the long- and short-range ordered structure of lotus seed starch-chlorogenic acid complexes were reduced compared with lotus seed starch under autoclaving treatment. The relative crystallinity of A-LS-CA complexes decreased from 23.4 % to 20.3 %, the value of R1047/1022 reduced from 0.87 to 0.80, and the proportion of amorphous region increased from 10.26 % to 13.85 %. In addition, thermal stability, storage modulus and loss modulus of lotus seed starch-chlorogenic acid complexes were reduced, indicating that the viscoelasticity of lotus seed starch gel was weakened with the addition of chlorogenic acid. It is remarkable that chlorogenic acid increased the proportion of resistant starch from 58.25 ± 1.43 % to 63.85 ± 0.96 % compared with lotus seed starch under autoclaving treatment. Here, the research results provided a theoretical guidance for the development of functional foods containing lotus seed starch.

Evolution of multi-scale structure and microbiota metabolism of lentil resistant starch during the dynamic fermentation in vitro

This study investigated the structural changes of resistant starch (RS) derived from autoclaved lentil starch (ALRS) and untreated lentil starch (ULRS) during in vitro colonic fermentation, as well as their regulatory effects on the composition of the intestinal microbiota. Following in vitro fermentation, both RS samples exhibited a progressive decrease in molecular weight and a gradual increase in double helix/order. Bifidobacterium was more abundant in ULRS during the initial period of fermentation, while ALRS showed higher abundance in the later stage. ALRS demonstrated greater production of short-chain fatty acids (SCFAs) compared to ULRS, likely attributed to its higher structural order and faster fermentation pattern. The distinct surface morphologies of ULRS and ALRS played a crucial role in determining the accessibility of RS substrates for microbial fermentation. These different structural patterns also influenced the shifts in microbial composition in fecal cultures, leading to variations in SCFAs production through anaerobic fermentation.

Perspectives on Starch Structure, Function, and Synthesis in Relation to the Backbone Model of Amylopectin.

Understanding functionality of polysaccharides such as starch requires molecular representations that account for their functional characteristics, such as those related to gelatinization, gelation, and crystallization. Starch macromolecules are inherently very complex, and precise structures can only be deduced from large data sets to generate relational models. For amylopectin, the major, well-organized, branched part of starch, two main molecular representations describe its structure: the classical cluster model and the more recent backbone model. Continuously emerging data call for inspection of these models, necessary revisions, and adoption of the preferred representation. The accumulated molecular and functional data support the backbone model and it well accommodates our present knowledge related to the biosynthesis of starch. This Perspective focuses on our current knowledge of starch structure and functionality directly in relation to the backbone model of amylopectin.

Bactericidal effect of ultrasound on glutinous rice during soaking and its influence on physicochemical properties of starch and quality characteristics of sweet dumplings

The soaking process of glutinous rice allows the growth and reproduction of microorganisms, which can easily cause food safety problems. In this work, the effects of different ultrasonic powers (150 W, 300 W, 450 W, and 600 W) on the bactericidal effect of glutinous rice, the physicochemical properties of starch and the quality characteristics of sweet dumplings were studied. Compared with soaking for 0 and 2 h, sonication of glutinous rice after soaking for 4 h was more effective at reducing the number of microorganisms in soaked glutinous rice, and the bactericidal effect increased with increasing ultrasound intensity. After 30 min, the total number of bacteria decreased by 2.04 log CFU/g. Moreover, ultrasonic treatment destroys the grain structure of glutinous rice starch, resulting in the formation of dents and cracks on the starch surface, increasing the amylose content, improving its expansion, reducing its short-range order and relative crystallinity, and altering its gelatinization characteristics. In addition, ultrasonic treatment increased the soup transparency of sweet dumplings from 51.8 % to 63.95 %, reducing their hardness, chewiness and adhesiveness. In summary, ultrasonic treatment can not only effectively kill microorganisms in soaked glutinous rice but also improve the quality of glutinous rice dumplings by changing the physicochemical properties of glutinous rice starch. The results of this study provide theoretical support for the application of ultrasonic technology in glutinous rice food production.

The Effect of Maltose on Structural, Physicochemical, and Digestive Properties of Lentil Starch under Electron Beam Irradiation.

This study investigated the effects of electron beam irradiation (EBI) on the structural, physicochemical, and functional properties of lentil starch with varying maltose content. EBI did not significantly disrupt the starch's surface structure or cause amorphization of starch and maltose crystals, but it significantly reduced the intensity of starch's XRD peaks. The presence of maltose intensified internal growth ring damage, leading to more cross-link and rearrangement between short chains, improving short-range ordering of lentil starch and enhancing starch's solubility and thermal stability. Additionally, adding maltose that EBI then treats can lead to an increased content of slowly digestible starch in samples.

Fabrication and characterization of tea seed starch-tea polyphenol complexes

This study investigates the complexation between tea seed starch (TSS) and tea polyphenols (TPs) at varying concentrations (2.5, 5.0, 7.5, and 10.0 %). The objectives can expand the knowledge of TSS, which is a novel starch, and to examine how TPs influence the structure and physicochemical properties of the complexes. Results indicate that TPs interact with TSS through hydrogen bonding, altering granule morphology and disrupting ordered structure of starch. Depending on the concentration, TPs induce either V-type or non-V-type crystal structures within TSS, which had bearing on iodine binding capacity, swelling, pasting, gelatinization, retrogradation, rheology, and gel structure. In vitro digestibility analysis reveals that TSS-TPs complexes tend to reduce readily digestible starch while increasing resistant starch fractions with higher TP concentrations. Thus, TSS-TPs complexes physicochemical and digestibility properties can be modulated, providing a wide range of potential applications in the food industry.

High-Resistant Starch Based on Amylopectin Cluster via Extrusion: From the Perspective of Chain-Length Distribution and Structural Formation.

Resistant starch (RS) has the advantage of reshaping gut microbiota for human metabolism and health, like glycemic control, weight loss, etc. Among them, RS3 prepared from pure starch is green and safe, but it is hard to achieve structural control. Here, we regulate the crystal structure of starch with different chain-length distributions (CLDs) via extrusion at low/high shearing levels. The change in CLDs in extruded starch was obtained, and their effects on the fine structure (Dm, dBragg, dLorentz, degree of order and double helix, degree of crystal) of RS and its physicochemical properties were investigated by SAXS, FTIR, XRD and 13C NMR analyses. The results showed that the RS content under a 250 r/min extrusion condition was the highest at 61.52%. Furthermore, the crystalline system induced by high amylopectin (amylose ≤ 4.78%) and a small amount of amylose (amylose ≥ 27.97%) was favorable for obtaining a high content of RS3-modified products under the extruding environment. The control of the moderate proportion of the A chains (DP 6-12) in the starch matrix was beneficial to the formation of RS.

The influence mechanism of pH and polyphenol structures on the formation, structure, and digestibility of pea starch-polyphenol complexes via high-pressure homogenization

The formation of starch-polyphenol complexes through high-pressure homogenization (HPH) is a promising method to reduce starch digestibility and control postprandial glycemic responses. This study investigated the combined effect of pH (5, 7, 9) and polyphenol structures (gallic acid, ferulic acid, quercetin, and tannic acid) on the formation, muti-scale structure, physicochemical properties, and digestibility of pea starch (PS)-polyphenol complexes prepared by HPH. Results revealed that reducing pH from 9 to 5 significantly strengthened the non-covalent binding between polyphenols and PS, achieving a maximum complex index of 13.89 %. This led to the formation of complexes with higher crystallinity and denser structures, promoting a robust network post-gelatinization with superior viscoelastic and thermal properties. These complexes showed increased resistance to enzymatic digestion, with the content of resistant starch increasing from 28.66 % to 42.00 %, rapidly digestible starch decreasing from 42.82 % to 21.88 %, and slowly digestible starch reducing from 71.34 % to 58.00 %. Gallic acid formed the strongest hydrogen bonds with PS, especially at pH 5, leading to the highest enzymatic resistance in PS-gallic acid complexes, with the content of resistant starch of 42.00 %, rapidly digestible starch of 23.35 % and slowly digestible starch of 58.00 %, and starch digestion rates at two digestive stages of 1.82 × 10–2 min−1 and 0.34 × 10–2 min−1. These insights advance our understanding of starch-polyphenol interactions and support the development of functional food products to improve metabolic health by mitigating rapid glucose release.

Structural characterization and physicochemical properties of grain amaranth starch

With potato starch (PS) and corn starch (CS) as the controls, the structure and physicochemical properties of grain amaranth starch (GAS) and its binding with dihydromyricetin were investigated in this study. The results indicated that GAS granules were small in size (3.21 ± 0.13 μm) and had a low amylose content (11.57 ± 0.91%). GAS exhibited low paste clarity, solubility, and swelling power, but demonstrated good freeze-thaw stability and resistance to retrogradation. Although the pasting temperature of GAS was high (75.88 ± 0.03 °C), its peak viscosity, breakdown viscosity, and setback viscosity were significantly lower than those of PS and CS. GAS was classified as A-type starch, with a high molecular weight and broad distribution (Mw, 3.96 × 107 g/mol; PDI, 2.67). For its chain length distribution, chain B1 had the highest proportion (50.09%), while chain B3 had the lowest proportion (13.50%). The complexation of GAS with dihydromyricetin effectively enhanced its ABTS and DPPH free radical scavenging capacities.

The structural and digestive properties of indica rice starch-fatty acid complexes

The structural and digestive properties of indica rice starch-fatty acid complexes and the effects of lipoxygenase on the structural and digestive properties of the complexes were examined in this study. The complexes were characterized by scanning electron microscopy, X-ray diffraction, Fourier transform-infrared spectroscopy and Raman spectroscopy. The results showed that indica rice starch had the highest molecular chain order and the highest crystallinity, and the crystallization disappeared after gelatinization, and the formation of indica rice starch-fatty acid complexes promoted the transformation of starch crystal structure from A-type to V-type. Lipoxygenase reduced the regularity of starch molecular crystal structure in the complexes, while enzyme protein improved the order of starch molecular structure in the complexes. The regularity of starch crystal structure in the complexes could improve with the increase of composite temperature and the increase of fatty acid unsaturation. In vitro digestibility and in vitro digestion kinetics showed that the formation of indica rice starch-fatty acid complexes reduced the digestibility of indica rice starch to a certain extent. The RDS content of indica rice starch was 66.42 ± 0.39 %, and lipoxygenase reduced the reduction of rapidly digested starch content during complexes digestion, while enzyme protein increased the content of resistant starch.

Regulating the active hydroxyl group of starch: Revealing the evolution of hard carbon structure and sodium storage behavior

The active hydroxyl group of starch has a crucial effect in regulating the microstructure of hard carbon anodes for sodium-ion batteries. By optimizing the chemical structure of starch and controlling the pyrolysis process, high-performance hard carbon materials can be obtained. These active hydroxyl groups are primarily located on the terminal and ring structures of glucose units, exerting significant influence on the formation and performance of hard carbon. Our results demonstrate that low-temperature oxidation treatment effectively modifies the terminal hydroxyl groups in precursor materials, facilitating chain cross-linking and leading to a more robust hard carbon structure. This cross-linking effect helps suppress excessive foaming during pyrolysis, thereby enhancing the stability of the hard carbon structure. Furthermore, by modifying the hydroxyl group on the ring structure of precursors, we can control the pyrolysis process, promote pore closure, and further improve the low plateau capacity of hard carbon anode materials from 153.95 to 219.58 mAh g −1. This study offers novel insights into harnessing and understanding starch's active hydroxyl groups in preparing hard carbon materials—a significant contribution towards optimizing their performance as anode materials.

Effect of Mild Alkali Treatment on the Structure and Physicochemical Properties of Normal and Waxy Rice Starches.

Mild alkali treatment can potentially be developed as a greener alternative to the traditional alkali treatment of starch, but the effect of mild alkali on starch is still understudied. Normal and waxy rice starches were subjected to mild alkali combined with hydrothermal treatment to investigate their changes in physicochemical properties. After mild alkali treatment, the protein content of normal and waxy rice starches decreased from 0.76% to 0.23% and from 0.89% to 0.23%, respectively. Mild alkali treatment decreased gelatinization temperature but increased the swelling power and solubility of both starches. Mild alkali treatment also increased the gelatinization enthalpy of waxy rice starch from 20.01 J/g to 25.04 J/g. Mild alkali treatment at room temperature increased the pasting viscosities of both normal and waxy rice starches, whereas at high temperature, it decreased pasting viscosities during hydrothermal treatment. Alkali treatment significantly changed the properties of normal and waxy rice starch by the ionization of hydroxyl groups and the removal of starch granule-associated proteins. Hydrothermal conditions promoted the effect of alkali. The combination of hydrothermal and alkali treatment led to greater changes in starch properties.

Optimisation of dry heat treatment conditions for modification of faba bean (Vicia faba L.) starch

Faba bean is a protein-rich starchy grain that is underutilised in the UK. The starch of faba bean can be modified using environmentally friendly methods like dry heat treatment (DHT) to enhance functional and its physicochemical properties. This study investigated the impact of dry heat temperature and time on the structure, functional and physicochemical properties of faba bean starch (FBS) using a two-factor central composite rotatable design. Factors (DHT temperature:100–150 °C and DHT time:0.5–5 h) with their respective α mid-point values led to 13 experimental runs. Selected pasting and functional properties were measured as response variables. Corn starch was included as a reference and compared with the FBS modified using the optimized conditions. DHT increased peak (approx. 2205–2267 cP), final (approx. 3525–3642 cP) and setback (approx. 1887–1993 cP) viscosities but decreased the amylose content of FBS. Colour, as measured by lightness value, morphology and crystalline type were not altered but the starches showed a loss of order and an increase in crystallinity after DHT. FBS appeared resilient to DHT but showed higher swelling power and pasting properties compared to the corn starch control. The optimum DHT conditions to produce starch with desirable properties are a temperature of 100 °C for 0.1716 h, with a desirability factor of 66 %.

Effect of Lycium barbarum L. polysaccharides on the quality of potato chips under low temperature frying and the mechanism of its action

Consumers increasingly desire healthier low-fat snack options. In this study, potato starch served as the substrate, and varying quantities of Lycium barbarum L. polysaccharide (0, 1, 3, and 5 g/100 g) were added to formula potato chips (FPC). The effect of LBPs on the sensory qualities, oil content, microstructure, and starch properties of FPC-LBPs was examined. The results showed that LBPs resulted in enhanced acceptability, reduced oil content, increased RS content, lower straight-chain starch leaching, and a gradual increase in the composite index (CI) of polysaccharides and starch in FPC-LBPs. The FPC-1LBPs exhibited the highest acceptability compared with the control samples. As the quantity of LBPs increased, the pores and cracks in the FPC-LBPs gradually decreased, and a polysaccharide wrapping layer formed on the surface of starch, which was the primary cause of the decrease in the oil content. With an increase in LBPs addition, the long-range and short-range ordered structure of starch progressively increased, and the hydrogen bonding interaction between LBPs and starch gradually strengthened, resulting in thinner FPC-LBPs. The enthalpy change of starch gradually decreased owing to LBPs, which delayed the pasting of starch and increased the RS content.

Effects of Controlled-Release Nitrogen Fertilizer at Different Release Stages on Rice Yield and Quality

The replacement of common urea with controlled-release nitrogen fertilizer can improve rice yield and quality, but the effect of controlled-release nitrogen fertilizer on rice yield and quality at different release stages is still unclear. In this experiment, two nitrogen application rates (240 kg/ha and 300 kg/ha) and five different nutrient release characteristics (urea and coated urea with controlled release periods of 30, 50, 70 and 90 days, respectively) were set up to explore the effects of nitrogen application rate, release characteristics and their interactions on rice yield, quality, starch structure, and physicochemical properties. The results showed that, compared with other controlled-release nitrogenous fertilizers, application of controlled-release nitrogenous fertilizers for 30 days and 90 days could increase rice yield (14.17% to 20.83%), and application of controlled-release nitrogenous fertilizers for 70 days and 90 days had the highest comprehensive evaluation of rice quality. The decrease of amylose content and the increase of protein content significantly improved the eating and nutritional quality of rice by changing the structure and physicochemical properties of starch particles. The results showed that in the comprehensive evaluation system based on rice yield and quality, under the condition of 300 kg/ha, controlled-release nitrogen treatment with a controlled release period of 90 days had the highest comprehensive score, which could increase rice yield and improve grain quality.

Differences in cooking taste and physicochemical properties between compound nutritional rice and common rice.

In this study, it was compared the physicochemical properties and cooking taste quality between four different types of compound nutritional rice (rice flour with the addition of other coarse grains, legumes, potatoes, and other powders, extruded as artificial rice grains) and common rice. We found that the protein and apparent amylose contents of compound nutritional rice were higher than that of common rice, up to 9.775% and 19.45% respectively. The γ-aminobutyric acid (GABA) and resistant starch contents were much lower than in common rice, and the dietary fiber content did not differ from that in common rice. The results of Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis revealed that the starch properties and structure of the compound nutritional rice changed due to high temperature and high pressure processing. In particular, the crystalline structures of starch became V-shaped. In addition, the results of artificial tasting and tasting meter showed that the taste of compound nutritional rice was generally inferior to that of common rice. In summary, compound nutritional rice had problems such as nutritional imbalance and poor taste. There was still a lot of room for improving the taste quality of compound nutritional rice. Therefore, the future development of compound nutritional rice should focus on both nutritional balance and taste improvement. The results of this paper also provided a certain theoretical basis for this.