Retrogradation Properties Of Starch Research Articles

Effect of Chemical Modification By Oxidation and Esterification Process On Properties of Starch: A Review

Starch is a carbohydrate or polysaccharide consisting of a large number of glucose units linked through glycosidic bonds and containing different amounts of amylose and amylopectin as macromolecules. Starch modification can be done physically, chemically, and enzymatically. The process of chemical modification of starch aims to separate the long glucose chains from the polymer molecules in order to reduce the high viscosity of the unmodified starch solution and thus maximize the possible amount of starch in technical applications This modification involves exploiting the many hydroxyl groups present in starch granules to introduce functional groups, resulting in changes in physicochemical and functional properties such as gelatinization, paste, and retrogradation properties of starch. Esterification and oxidation are types of chemical modification processes that can be applied to improve starch characteristics. However, the chemical modification process did not affect the morphology and had little effect on changing the structure of the starch

How to synchronously slow down starch digestion and retrogradation: A structural analysis study

Digestibility and retrogradation properties of starch are important for the nutrition and quality of starch-based foods. In this study, a new idea on the synchronous delay the starch digestion and retrogradation was proposed, and the regulation mechanism was explored from perspectives of structural evolution using 13C NMR, XRD and SAXS techniques as well as the molecular dynamics simulations. Results showed that the chestnut starch treated with hot extrusion and 8% catechins (HE-8% CA)## could reach highest anti-retrogradation rate (AR 76.63%) and lowest rapidly digestible starch content (RDS 64.55%) at day 24. The starch digestion was slowed down by increasing single/double helix, V-type crystallinity and compactness of aggregates, while retrogradation process was suppressed by inhibiting the packing of short-range ordered structure into long-range ordered structure. The hydrogen bonding and van der Waals forces were the main driving force for the interactions between flavonoid polyphenols and starch molecules. Overall, this study is instructive for further investigations on the synchronous modulation of functional properties of starch.

Effect of wheat gluten addition on the quality of thermal‐vacuum packaged Chinese steamed bread

AbstractBackground and objectivesIn order to investigate the effect of wheat gluten on thermal‐vacuum packaged Chinese steamed bread (CSB) quality during storage at room temperature, the wheat gluten addition levels of 0%, 1%, and 2% were set to study the effect on the protein structure, water mobility, starch retrogradation properties, and texture properties.FindingsWith the addition of wheat gluten, the β‐sheet content was increased and random coil content of thermal‐vacuum packaged CSB decreased. Wheat gluten enhanced the water holding capacity of CSB and restricted water migration, resulting in a lower content of bound water and higher content of less strongly bound water and free water according to the low‐field nuclear magnetic resonance (NMR). With the increase of wheat gluten, the diffraction peak intensity and relative crystallinity reduced. The elasticity and cohesion were higher, and the hardness, gumminess, chewiness, and resilience were lower than those in the control.ConclusionsThe results of this study revealed that the addition of wheat gluten can effectively inhibit moisture dispersion and starch retrogradation to delay the staling of CSB during storage.Significance and noveltyAs a natural food additive, wheat gluten can not only optimize protein structure and enhance nutritional value but also extend the shelf life of CSB. Therefore, these findings will promote industrial development of CSB.

Insights into the correlations between the size of starch at nano- to microscale and its functional properties based on asymmetrical flow field-flow fractionation

In this study, the starches were isolated from three botanical sources (i.e., rice, sweet potato, and lotus seed). The size distributions of starch granules and molecules were determined by asymmetrical flow field-flow fractionation (AF4), and compared with those measured from optical microscopy (OM) and dynamic light scattering (DLS). Furthermore, the starches were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC). AF4 coupled online with UV–visible, multiangle light scattering (MALS), and differential refractive index (dRI) detectors (AF4-UV-MALS-dRI) was employed for the investigation of the digestion and retrogradation properties of starches. Meanwhile, the relationships between the size of starch at nano- to microscale and its functional properties (i.e., digestibility, retrogradation, and thermal properties) were studied by Pearson correlation analysis. AF4-UV-MALS-dRI was proved to be a rapid and gentle method for the separation and size characterization of starches at both micro- and nano-molecule levels. Moreover, it was demonstrated that AF4-UV-MALS-dRI is a useful tool for the monitoring of the digestion and retrogradation properties of starches. The results suggested that the sizes of starch granules and molecules were to some extent correlated with their thermal properties and digestibility, but not with retrogradation property.

Effect of oat β-glucan addition on the staling properties of wheat-oat blended flour Chinese steamed bread

This study aimed to investigate the effect of different oat β-glucan additions (0%, 1%, 3%, 5%) on water mobility, starch retrogradation properties and Chinese steamed bread (CSB) quality in thermal-vacuum package CSB during storage at room temperature. With the increase of oat β-glucan, the total moisture content initially increased then decreased, while the hardness and cohesiveness initially decreased then increased. The weakly bound water T22 and free water T23 content increased, while the content of strongly bound water T21, relative crystallinity and long-range ordering decreased. During storage at room temperature, the thermal-vacuum package CSB presented mixed crystals of B-type and V-type, and the hardness, relative crystallinity and long-range order of CSB were increased, the specific volume of CSB initially increased then decreased, while the springiness, cohesiveness and resilience of CSB were decreased. Our findings revealed that oat β-glucan could alleviate the quality deterioration, moisture loss and starch stalling of CSB during storage. Oat β-glucan could effectively inhibit water migration and starch retrogradation of CSB, consequently inhibiting the staling. Therefore, small amount of oat β-glucan can be used as a new food additive to improve the dietary fiber content and extend the shelf life of staple CSB at room temperature.

Synergistic effect of extrusion and polyphenol molecular interaction on the short/long-term retrogradation properties of chestnut starch

The retrogradation properties of starch are closely related to the processing quality of starch-based foods. In this study, the synergistic effects of extrusion and the presence of polyphenols on the water distribution, rheological properties and short-term (1 day)/long-term (21 day) retrogradation of chestnut starch paste were investigated. Post extrusion complexation with catechins (CC)/proanthocyanidins (PC), the short- and long-term retrogradation were both inhibited and the anti-retrogradation rates (AR) during 1 and 21 days were as high as 100% and 44.17–69.30%, respectively. Owing to the destruction of starch chains by extrusion and interaction between starch and polyphenol molecules, the approach, entanglement and aggregation tendencies of starch molecules were all inhibited, which decreased the relative crystallinity (RC), flow resistance and storage modulus of starch paste and also increased the water-holding capacity. The starch retrogradation was thus suppressed. These results are beneficial for the development of starch-based products with high quality and lower retrogradation rate.

Comparison of the Grain Quality and Starch Physicochemical Properties between Japonica Rice Cultivars with Different Contents of Amylose, as Affected by Nitrogen Fertilization

In order to determine the effects of nitrogen fertilizer on the grain quality and starch physicochemical properties of japonica rice cultivars with different contents of amylose, normal amylose content (NAC) and low amylose content (LAC) cultivars were grown in a field, with or without nitrogen fertilizer (WN). The relationships between the amylose content, starch physicochemical properties and eating quality were also examined. Compared with WN, nitrogen fertilizer (NF) significantly increased the grain yield but markedly decreased the grain weight. In addition, the processing quality tended to improve, but the appearance quality and eating quality deteriorated under NF application. The grain yield was similar between NAC and LAC cultivars. However, the grain quality and starch physicochemical properties were significantly different between NAC and LAC cultivars. The palatability of the cooked rice was significantly higher in the LAC than in NAC cultivar, which was due to its lower amylose content, protein content, hardness, and retrogradation enthalpy and degree, and its higher stickiness, peak viscosity, breakdown, relative crystallinity and peak intensity. The amylose content and protein content were significantly negatively correlated with the palatability. The amylose content was significantly positively correlated with the final viscosity and setback, and was significantly negatively correlated with the relative crystallinity, peak intensity, gelatinization enthalpy and breakdown. Palatability was significantly positively correlated with peak viscosity, breakdown and peak intensity, and was significantly negatively correlated with the final viscosity, setback, and retrogradation enthalpy and degree. Therefore, the selection of a low amylose content japonica rice cultivar grown without nitrogen fertilizer can reduce the amylose and protein contents, as well as improving the pasting properties, starch retrogradation properties and eating quality of the cooked rice.

Wet milling of buckwheat cultivars and some quality properties of the fractions.

The hulled buckwheat cultivars (Aktaş cv. and Güneş cv.) were wet-milled, and then some chemical, yields, colour, functional properties, phenolic compound, antioxidant activity, and pasting, thermal and retrogradation properties of starches were investigated and compared with the wholegrain buckwheat flour (with hull) and buckwheat groat flour (without hull) of the same cultivars. Sodium dodecyl sulphate polyacrylamide gel electrophoresis patterns of flours and protein fractions were examined under reducing and non-reducing conditions. The hull, germ+dietary fibre, protein and starch fractions were collected. The total recovery for Aktaş cv. and Güneş cv. cultivars were 98.1% and 96.1%; total starch yields were 51.6% and 49.7%; pasting temperatures of the starches were found as 83.7 and 85.7°C; and final viscosities of starches were determined as 3.5 and 3.4 Pa·s, respectively. The resistant starch contents of starch fractions of Aktaş cv. ve Güneş cv. were found as 3.28% and 3.62%, respectively. The highest total phenolic compound contents were detected with dimethyl sulphoxide extraction in the germ+dietary fibre fractions. The highest 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and trolox equivalent antioxidant capacity were found in the hull fraction (as 81.7%) and germ+dietary fibre fraction (as 11.8 mmol/kg) of Aktaş cv. cultivar.

A new insight into the effect of starch nanocrystals in the retrogradation properties of starch

Starch nanocrystals (SNC) are having the potential to control the retrogradation of starch; however, their efficacy to control retrogradation in starch was not fully understood. In this investigation, starch nanocrystals (SNC) were synthesized from rice (RS) and wheat (WS) starches, and their influence on short and long-term retrogradation properties of the starch-SNC mixture was extensively studied. Starch-SNC mixture was prepared by mixing SNC of rice and wheat with their respective starches in different proportions (5%, 10%, and 15%). The addition of SNC to the respective starch samples significantly (p ≤ 0.05) reduced the short-term retrogradation properties of starch-nanocrystal mixtures. The non-nucleated amylopectin units present in the starch-nanocrystal mixture inhibited the reassociation of amylose chains resulted in lower short-term retrogradation of the starch-nanocrystal mixtures. The setback and final viscosity of the starch-nanocrystal mixture decreased with an increase in the SNC concentration. Increased values of ΔHR (enthalpy of retrogradation), hardness, syneresis, and lower freeze-thaw stability of starch–SNC mixtures indicated that long-term retrogradation was not reduced due to the addition of SNC. Hence, the present study confirms the role of SNC as a promising additive for retarding short-term retrogradation properties of various starchy products.

Effect of thermal packaging temperature on Chinese steamed bread quality during room temperature storage

In order to investigate the influence of different packaging temperature on thermal-vacuum packaged Chinese steamed bread (CSB) quality under room temperature storage, the packaging temperatures of 50 °C, 70 °C and 90 °C were set respectively to study the effect on the packaging vacuum degree (VD) and starch retrogradation properties. The VD and moisture content of thermal-vacuum packaged CSB significantly increased with the increase of the packaging temperature from 50 °C to 90 °C, while the hardness of CSB decreased, and there was no significant difference in moisture migration during room temperature storage. The results of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and small angle X-ray scattering (SAXS) indicated that CSB packaged at different temperatures formed B-type crystals, leading to an enhanced the ordered and dense state of starch structure, and the semi-crystalline growth ring structure disappeared during storage. The influence of different packaging temperatures on VD of CSB could effectively hinder the formation of ordered and dense state of CSB starch, consequently delaying the crystallization of amylopectin and inhibiting the progress of staling. The result of this study is of great significance for improving the quality of starchy foods and guiding the industrial development of Chinese steamed bread.

A versatile three-dimensional foam fabrication strategy for soft and hard tissue engineering

The fabrication strategies of three-dimensional porous biomaterials have been extensively studied and well established in the past few decades, yet the biocompatibility and versatility of porous architecture preparation is still lacking. Herewith, we present a novel and green 3D porous foam fabrication technique for both soft and hard engineering. By utilizing the gelatinization and retrogradation properties of starches, stabilized porous constructs made of various building blocks, from living cells to ceramic particles, were created for the first time. In soft tissue engineering applications, 3D cultured tissue foam (CTF) with controlled cell release properties was developed, and foams constituting osteoblasts, fibroblasts and vascular endothelial cells all exhibited high mechanical stability and preservation of cell viability or functions. More importantly, the CTF achieved sustained self-release of cells controlled by serum concentration (containing amylase) and the released cells also maintained high viability and functions. In the context of hard tissue engineering applications, ceramic/bioglass (BG) foam scaffolds were developed by a similar starch-assisted foaming strategy where the resultant bone scaffolds of hydroxyapatite (HA)/BG and Si3N4/BG possessed >70% porosity with interconnected macropores (sizes 200 ∼ 400 μm), fine pores (sizes 1 ∼ 10 μm) and superior mechanical properties despite the high porosity. Additionally, in vitro and in vivo evaluations of the biological properties revealed that porous HA/BG foam exhibits the desired biocompatibility and osteogenesis. The in vivo study indicated new bone ingrowth after 1 week and significant increases in new bone volume after 2 weeks. In conclusion, the presented foaming strategy provides opportunities for biofabricating CTF with different cells for different target soft tissues and preparing porous ceramic/BG foams with different material components and high strengths, showing great versatility in soft and hard tissue engineering.

Effects of Heat Stress and Cultivar on the Functional Properties of Starch in Chinese Wheat

Heat stress during the grain‐filling stage is a major limiting factor for improving Chinese wheat production, and its effect on functional properties of flours and starches in 10 leading cultivars from the Yellow and Huai Valleys grown under normal and heat‐stress environments was investigated. Heat stress during the grain‐filling stage decreased total starch content but increased protein and lipid contents of wheat grains. Amylose content of wheat starch was little altered under a heat‐stress environment. Heat stress did not significantly change swelling power and starch solubility of wheat starches but significantly decreased swelling power of wheat flours. Pasting viscosities of wheat starches and flours were affected differentially by heat stress. Heat stress had a significant effect on gelatinization and retrogradation properties of starches. The in vitro enzymatic digestibility of wheat starches was affected slightly by heat stress. Analysis of variance indicated that heat stress had a significant effect on some functional properties of starch and flour, although the largest source of variability in these properties was cultivar.

Pasting, rheological, and retrogradation properties of starches from dual‐purpose sorghum lines

In this study, we evaluated the functionality of starches extracted from dual‐purpose sorghum lines (KDFGS1, KDFGS6, KDFGS9, and KDFGS20). There were no significant differences in swelling factor, solubility, or paste clarity among the lines. Sorghum starches exhibited similar pasting patterns with differences in peak viscosity, breakdown, and setback. Starch pastes had similar consistency and had shear‐thinning behavior. Sorghum starches showed good gel setting ability, while hardness, cohesiveness, and springiness were not statistically different among the lines. Starch from KDFGS20 had lower retrogradation rate and syneresis during storage at 4°C. Starch pastes were highly susceptible to successive freeze‐thaw cycles. Approximately 80% water was separated after five freeze‐thaw cycles. Our findings revealed that sorghum starches from dual‐purpose lines had acceptable water binding, viscosifying, and gelling properties, making them suitable for food applications that do not require starches with high freezing stability.

Relationship between structure and retrogradation properties of corn starch treated with 1,4-α-glucan branching enzyme

Corn starch was selected to produce a product that undergoes slow retrogradation after enzymatic modification using the 1,4-α-glucan branching enzyme (GBE) isolated from Geobacillus thermoglucosidans STB02. GBE treatment of corn starch could time-dependently increase the number of α-1,6 branch points, and decrease the average chain length of amylopectin and the amylose content. Meanwhile, GBE treatment also led to reduction in setback values and relative crystallinity, indicating lower short- and long-term retrogradation of starch, respectively. After treatment for 10 h, the number of α-1,6 branch points was increased by 64.6%, while the average chain length of amylopectin and the amylose content were decreased by 11.8% and 29.5%, respectively; the setback values and relative crystallinity of starch were reduced by 45.7% and 22.0%, respectively. More importantly, the relationship between structure and retrogradation properties of corn starch treated with GBE could be fairly well described by simple linear regression. The setback value of starch was positively correlated with amylose content (R2 = 0.9896). In starch pastes aged two weeks at 4 °C, the relative crystallinity showed positive correlations with the average chain length of amylopectin (R2 = 0.9780) and the amylose content (R2 = 0.9654). These results suggest that the retrogradation properties of starch can be improved by reducing the amylose content and average chain length of amylopectin, which may shed light on the further development of modified starches with low retrogradation.

The effects of ultra-high pressure on the structural, rheological and retrogradation properties of lotus seed starch

Lotus seed starch in water (15%, w/w) was subjected to ultra-high pressure (UHP, 100–600 MPa) for 30 min. The effects of UHP on the structural, rheological and retrogradation properties of starch were investigated using polarized light microscopy, solid-state 13C CP/MAS NMR, rheometry, and differential scanning calorimetry. At 600 MPa, there was loss of the polarization cross, but some birefringence remained, indicating gelatinization. The 13C CP/MAS NMR results revealed a reduction in crystallinity and peak intensity in the crystalline state with increasing pressure. Native and UHP-treated starch pastes exhibited shear-thinning pseudoplastic behavior. Both G′ and G″ increased significantly at 100–500 MPa and decreased at 600 MPa, indicating that excessive pressurization weakens gel structures. UHP-treated starch pastes recovered more slowly their original structures under low-high-low shear conditions than native starch. During storage, UHP-treated starch gels had higher Avrami exponent values and lower recrystallization rates compared with native starch, which suggested a lower retrogradation tendency.

Rheological and textural studies of fresh and freeze-thawed native sago starch–sugar gels. II. Comparisons with other starch sources and reheating effects

The viscoelastic and textural properties of freshly prepared and freeze-thawed sago starch–sugar gels were studied in comparison with other native starches from corn, wheat, tapioca, and potato. The gelatinisation and retrogradation properties of starches were studied using a DSC while the pasting properties of starch–sugar mixtures during the cooking period were studied using a starch pasting cell. The freeze-thaw stability of gels was evaluated by gravimetric measurements of the water of syneresis. The different starches gave properties which varied following to their botanical sources. High-amylose cereal starches (wheat and corn) produced harder gels, while low-amylose root starch (tapioca) produced softer gels. Sago and potato gels showed close similarities in their viscoelastic and textural characteristics. Although the freeze-thaw cycle greatly increased the viscoelasticity and hardness of these two gels, reheating at high temperature significantly reduced these negative effects and resulted in partial recovery of the gel structures. Sago starch produced gels with very low syneresis and high cohesiveness, implying its potential use as a gelling agent in the frozen food industries.

Physicochemical Properties of Waxy and Normal Maize Starches Irradiated at Various pH and Salt Concentrations

AbstractWaxy and normal maize starches of various pH values and salt contents were prepared, irradiated with gamma rays (5–20 kGy) and their molecular structure, pasting viscosity and rheological properties determined. Average molar mass and size of both waxy and normal maize starches decreased considerably by irradiation from >338.0×106 to <39.4×106 g/mol and from >237.5 to <125.2 nm, respectively. Adjustments of pH had little influence on the average molar mass and size of irradiated starch, whereas incorporation of salt greatly reduced the molar mass and size of irradiated waxy and normal maize starches. As the pH increased from 4 to 8, the pasting viscosity of the irradiated starches decreased from 1032 to 279 mPa s in waxy and from 699 to 381 mPa s in normal starches. Pasting viscosity of both irradiated waxy and normal starch decreased from 689 to 358 mPa s and from 327 to 184 mPa s as the salt concentration increased from 1 to 5%. The G′ of gels, determined during cooling from 90 to 10°C or storage for 8 h, decreased in irradiated waxy and normal starches by pre‐conditioning at pH 8 and in irradiated waxy starches by pre‐conditioning at 5% NaCl. With 5% NaCl, G′ of irradiated normal maize starch during cooling increased up to the irradiation level of 10 kGy, and increased during storage for 8 h at all levels of irradiation. Incorporated salt prior to irradiation appears to induce incremental modifications in the molecular structure, rheological and retrogradation properties of starch by boosting the degradation of molecules.

Determination of thermal and retrogradation properties of rice starch using near-infrared spectroscopy

Starch is a major component of rice grain and thus plays an important role in grain quality. For breeding rice with improved quality, the thermal and retrogradation properties of starch may be routinely measured. Since direct measurement is time-consuming and expensive, rapid predictive methods based on near-infrared spectroscopy (NIRS) can be applied to measure these quality parameters. In this study, calibration models for measurement of thermal and retrogradation properties were built from the spectra of grain and flour samples. The results indicated that both grain and flour spectra could give similar accuracy ( r 2=∼0.78) in determining the peak temperature ( T p) and conclusion temperature ( T c) of gelatinization. However, flour spectra ( r 2=0.80) were superior to the grain spectra ( r 2=0.73) in measuring onset temperature ( T o). Furthermore, the thermal properties of width at half peak height (Δ T 1/2) and enthalpy of gelatinization (Δ H g), and retrogradation properties of enthalpy of retrogradation (Δ H r) and retrogradation percentage ( R%) could only be successfully modeled with the flour spectra. The models reported in the present study are usable for routine screening of a large number of samples in early generation of selection in breeding programs. For accurate assay of the thermal and retrogradation properties, however, direct instrumental measurement should be employed in later generations.

Variation in the Chain‐length Distribution Profiles of Endosperm Starch from Triticum and Aegilops Species

AbstractThe baseline variation data on the chain‐length distribution profiles of endosperm starch were acquired for use as a criterion for variation among bread wheat (Triticum aestivum L.) cultivars/lines. A total of 126 starch samples isolated from closely related species belonging to the Triticum‐Aegilops group, i.e., five Triticum and 22 Aegilops species, were examined. Their side‐chains were debranched by isoamylase and chain‐length distribution profiles were determined by high‐performance anion exchange chromatography with pulsed amperometric detection (HPAEC‐PAD). An averaged chain‐length distribution profile calculated from all data indicated that the most abundant side‐chain had a degree of polymerization (DP) of 11 and its proportion based on relative peak area was 7.5%. The side‐chains were classified into four groups, and the average proportions of each group were as follows; DP 6–12, 28.5% (range 26.3–30.9%); DP 13–24, 48.6% (46.2–50.8%); DP 25–36, 13.7% (12.8–15.2%) and DP ≥37, 8.9% (7.2–10.6%). The chain‐length distribution profiles of Triticum and Aegilops species were essentially similar and no peculiar profile was observed. The range of the variation in the proportion of side‐chain groups, however, was comparable to the difference between waxy and non‐waxy bread wheat starches and among starches from wheat grown at different temperatures; this would affect the gelatinization and retrogradation properties of starch.