Properties Of Wheat Starch Research Articles

The formation of starch-lipid complexes by microwave heating

This study investigated the impact of microwave treatment on the formation of starch-lipid complexes, and physicochemical properties of wheat starch (WS) fortified with lipids, such as lauric acid (LA), glycerol monolaurate (GML), and stearic acid (SA). Specimens were prepared using a conventional water bath and microwave heating and evaluated using macrostructural and microstructural analyses. Iodine staining and scanning electron microscopy revealed interplay between WS and LA. Diffraction peaks around 7.5°, 13°, and 20° and the absence of the absorption band in the 2850 cm−1 were observed in microwave treated WS-lipid samples than conventional water bath samples. Further, more type I complexes were formed in WS-LA microwave-assisted samples, as demonstrated by differential scanning calorimetry. Additionally, more resistant starch was formed in specimens treated by microwave than water bath treated counterparts, the finding that was proved by in vitro enzymatic hydrolysis. In short, the current study may suggest the applications of microwave treatment in foods for hypoglycemia.

Effects of isomalt on the quality of wheat flour dough and spicy wheat gluten sticks

SummaryThe effects of different isomalt concentrations on the quality of wheat flour dough and spicy wheat gluten sticks (SWGS) were evaluated at the physical, structural and molecular levels. The results showed that the radial expansion rate (RER) and oil absorption rate (OAR) of SWGS increased first and then decreased with increased isomalt supplementation, which reached the maximum at 3 wt%. The pasting properties of wheat starch also changed, and the peak viscosity, breakdown and setback were decreased with the addition of isomalt. Dynamic rheological properties results showed that the storage modulus (G') and loss modulus (G'') increased with the addition of isomalt, which may be attributed to the reinforcement of gluten network structure by hydrogen bonding of isomalt. Scanning electron microscopy (SEM) images illustrated that the SWGS surface becomes smooth and the broken gluten structure was reduced after the addition of different isomalt levels compared with the control group. Overall, the wheat flour dough quality analysis showed that the addition of isomalt could generate a close binding with wheat starch and protein and further strengthen the internal structure of gluten through isomalt hydrogen bonds.

Structural, physicochemical and long-term retrogradation properties of wheat starch treated using transglucosidase

To reduce the wheat-flour-based food texture and flavor deterioration caused by starch retrogradation, herein wheat starch, the most ingredient in wheat flour, was modified by transglucosidase to delay long-term retrogradation of wheat starch. The study proposed promising data of transglucosidase-treated starch about structure, crystallinity and retrogradation kinetics. Structural properties showed that transglucosidase treatment shortened the average chain length from 19.49 to 16.10 and induced the dominance of amorphous state. Moreover, branching degree increased from 14.11% to 17.97% after transglucosidase treatment, resulting in higher water mobility. Amylose content increased from 25.33% to 59.00% due to the hydrolysis ability of transglucosidase. Relative crystallinity of the retrograded starches decreased from 24.33% to 14.50%. Furthermore, the Avrami parameters demonstrated that transglucosidase treatment significantly retarded the retrogradation rate of wheat starch due to the decrease of re-crystalline rate. The outcoming would supply a solid theory foundation for exploring the wheat staple foods with higher qualities.

Holistic View of Starch Chemistry, Structure and Functionality in Dry Heat-Treated Whole Wheat Kernels and Flour

Heat treatment is used as a pre-processing step to beneficially change the starch properties of wheat flour to enhance its utilisation in the food industry. Heat-treated wheat flour may provide improved eating qualities in final wheat-based products since flour properties predominantly determine the texture and mouthfeel. Dry heat treatment of wheat kernels or milled wheat products involves heat transfer through means of air, a fluidising medium, or radiation—often resulting in moisture loss. Heat treatment leads to changes in the chemical, structural and functional properties of starch in wheat flour by inducing starch damage, altering its molecular order (which influences its crystallinity), pasting properties as well as its retrogradation and staling behaviour. Heat treatment also induces changes in gluten proteins, which may alter the rheological properties of wheat flour. Understanding the relationship between heat transfer, the thermal properties of wheat and the functionality of the resultant flour is of critical importance to obtain the desired extent of alteration of wheat starch properties and enhanced utilisation of the flour. This review paper introduces dry heat treatment methods followed by a critical review of the latest published research on heat-induced changes observed in wheat flour starch chemistry, structure and functionality.

Wheat starch-tannic acid complexes modulate physicochemical and rheological properties of wheat starch and its digestibility

In this study, the interactions of wheat starch (WS) and tannic acid (TA) were investigated for their gelatinization, pasting, structural, rheological properties and digestibility of wheat starch. TA was either complexed with starch (WS-TA complexes) or mixed with starch (WS-TA mixtures) right before the characterization of its properties. The increase of melting enthalpy and temperature range (Tpeak - Tonset) associated with melting of amylose-lipid complex and the increase in the X-ray diffraction peak at 2θ = 20° possibly indicated the formation of inclusion types of complexes. The appearance of an endothermic transition at 130–160 °C indicated the formation of non-inclusion types of complexes. Non-inclusion type of complexes were mostly formed by co-gelatinization of WS-TA mixtures, while inclusion complexes would be mostly formed by complexation of TA with ungelatinized starch. TA in mixtures increased G′ and viscosity and decreased frequency dependency of the moduli, thus producing a stronger gel. TA in complexes decreased G′ and viscosity at low TA%, thus producing a weak gel, but increased gel strength at high TA%. The storage moduli G′ increased depending on the amount of TA involved in non-inclusion complexes. The formation of complexes between WS and TA largely slowed down the digestibility of gelatinized starch. The insights gained in this study provide opportunities to modulate starch techno-functional properties and digestibility in processing of starchy food.

The effect of annealing under acid or alkaline environment on the physicochemical and functional properties of wheat starch

The annealing of wheat starch was performed in dilute acid and alkaline media at 40 °C and 45 °C. To highlight the effect of these processes on wheat starch, the scanning electron microscopy and the optic microscopy under normal and polarized light, the Wide-Angle X-ray Scattering patterns and the colour parameters were analysed without revealing significant changes in comparison to the native wheat starch and samples submitted to the classical annealing process in pure water. Most striking changes induced were observed upon additional hydrothermal treatment above wheat starch gelatinization temperatures and when analysing the water-binding capacity and the solubility, the starch granules swelling kinetics, the pasting behaviour of starch-water dispersion as well as the flow properties of gels recovered. It is likely that the complementary changes induced by these variants of annealing are meanly related to the restructuration of the amorphous phase inside granules that modify irreversibly their swelling capacity as well as their susceptibility to collapse upon further hydrothermal treatments. Although the magnitude of the changes induced by these processes seems to depend on the incubation temperature, the same trends were observed when compared the results from the two incubation temperatures applied. Coupling the annealing process with incubation in diluted acid or alkaline media can be used as effective way to expand the possibilities of using wheat starches in various industries.

Gelatinization, Retrogradation and Gel Properties of Wheat Starch-Wheat Bran Arabinoxylan Complexes.

Gelatinization, retrogradation and gel properties of wheat starch–wheat bran arabinoxylan (WS–WBAX) complexes have been evaluated. The results of rapid viscosity analyzer (RVA), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) confirmed that WBAX samples with larger Mw and branching degree (HWBAX) significantly impeded gelatinization process of starch by effectively reducing the amount of water available for starch gelatinization. DSC analysis showed that both molecular characteristics and additive amount of WBAX samples have an effect on the long-term retrogradation behavior of starch. For the rheological studies of WS–WBAX mixed gels, the elastic moduli (G’) and shear viscosity of WS–WBAX mixed gels increased with the increase in additive amount of WBAX. WS–HWBAX mixed gels exhibited the lower G’ compared with starch gels containing WBAX with lower Mw and branching degree (LWBAX) at the same amount. The scanning electron micrographs (SEM) revealed that the microstructures of WS–WBAX mixed gels were mainly affected by the amount of WBAX, but hardly by the molecular characteristics of WBAX. Texture profile analysis (TPA) showed that the cohesiveness of fresh WS–WBAX mixed gels became larger with an increase in the WBAX addition amount. The hardness of WS–WBAX mixed gels tended to increase over the 14-day storage.

Understanding Wheat Starch Metabolism in Properties, Environmental Stress Condition, and Molecular Approaches for Value-Added Utilization.

Wheat starch is one of the most important components in wheat grain and is extensively used as the main source in bread, noodles, and cookies. The wheat endosperm is composed of about 70% starch, so differences in the quality and quantity of starch affect the flour processing characteristics. Investigations on starch composition, structure, morphology, molecular markers, and transformations are providing new and efficient techniques that can improve the quality of bread wheat. Additionally, wheat starch composition and quality are varied due to genetics and environmental factors. Starch is more sensitive to heat and drought stress compared to storage proteins. These stresses also have a great influence on the grain filling period and anthesis, and, consequently, a negative effect on starch synthesis. Sucrose metabolizing and starch synthesis enzymes are suppressed under heat and drought stress during the grain filling period. Therefore, it is important to illustrate starch and sucrose mechanisms during plant responses in the grain filling period. In recent years, most of these quality traits have been investigated through genetic modification studies. This is an attractive approach to improve functional properties in wheat starch. The new information collected from hybrid and transgenic plants is expected to help develop novel starch for understanding wheat starch biosynthesis and commercial use. Wheat transformation research using plant genetic engineering technology is the main purpose of continuously controlling and analyzing the properties of wheat starch. The aim of this paper is to review the structure, biosynthesis mechanism, quality, and response to heat and drought stress of wheat starch. Additionally, molecular markers and transformation studies are reviewed to elucidate starch quality in wheat.

Effects of β-amylase treatment conditions on the gelatinization and retrogradation characteristics of wheat starch

The study aims to investigate the change of gelatinization and retrogradation properties of wheat starch (WS) after β-amylase treatment with different activities and different hydrolysis times, and to determine the relationship between the properties and treatment conditions. The contents of total starch, amylose and amylopectin in enzymatic treated samples were determined, and it was found that β-amylase treatment hydrolyzed the samples and increased the amylopectin content. The rapid viscosity analysis (RVA), differential scanning calorimetry (DSC), X-ray diffraction (XRD) and total texture analysis (TPA) were used for investigation. The gelatinization temperature increased but the overall viscosity including the setback and ΔHg decreased with increasing β-amylase activity or treatment time. Compared with WS, the hardness, ΔHr and recrystallization degree of samples decreased during storage, but the crystal structure still remained A-type. The crystallization rate constants of 10–50 U samples decreased by 25.1–41.9% and 10–50 min samples decreased by 7.6–54.6% according to the Avrami model. It was proved that the crystallization rate and retrogradation rate of the samples were slowed down. The results showed that β-amylase treatment had both short-term and long-term inhibition effects on WS aging and there was a stronger correlation between processing time and effect. And higher β-amylase activity had a stronger inhibition effect under the same hydrolysis time.

Effects of two contrasting dietary polysaccharides and tannic acid on the digestive and physicochemical properties of wheat starch.

In this study, konjac glucomannan, κ‐carrageenan, and tannic acid were selected to study the effects of different combinations on the in vitro digestibility and physicochemical properties of wheat starch. Results showed that the addition of konjac glucomannan, κ‐carrageenan, and tannic acid could decrease the digestion of starch and increase the content of resistant starch. Besides, the two polysaccharides weakened the extent of tannic acid on starch digestion. Moreover, although the two polysaccharides had different effects on the in vitro digestion of starch, they had no significant increase in the content of resistant starch. DSC and XRD results demonstrated that the polysaccharides and tannic acid showed synergistic effects on the rebuilding of starch microstructure. FTIR results further manifested that κ‐carrageenan and konjac glucomannan could significantly increase the strength of hydrogen bonds in starch. At the same time, the addition of tannic acid would weaken the molecular interaction between polysaccharides and starch. SEM and CLSM results showed that tannic acid added to the polysaccharide–starch mixture not only interacted with starch but also influenced the structure of polysaccharide gel.

Effect of wheat bran dietary fiber on structural properties of wheat starch after synergistic fermentation of Lactobacillus plantarum and Saccharomyces cerevisiae

This study investigated the changes in the structure of wheat starch after synergistic fermentation of Lactobacillus plantarum and Saccharomyces cerevisiae at different wheat bran dietary fiber (WBDF) levels. The results showed that WBDF was slightly resistant to the decrease in acidity within the fermentation system. The amylose content decreased from 32.12% to 19.92% (P < 0.05), amylose/amylopectin ratio decreased from 0.47 to 0.25 (P < 0.05), and relative crystallinity decreased from 12.17% to 9.40% (P < 0.05) in the samples containing WBDF compared with the control. Scanning electron microscopy showed more eroded starch as the WBDF level increased. Fourier-transform infrared spectroscopy revealed a decrease in the starch-hydrogen binding absorbance in the 3600-3000 cm-1 wavemumber; and the 1047/1022 and 995/1022 cm-1 data indicated an increase in the degree of order and degree of double helix of the samples containing WBDF. The results of the study might help understand the interaction between dietary fibers and starch during fermentation and guide the production of fermented high-fiber flour products.

Impact of superheated steam on the moisture transfer, structural characteristics and rheological properties of wheat starch

Superheated steam treatment (SST) can improve cereal-based foodstuff quality. Starch is the major component of cereal-based foodstuffs, playing a key role in food quality. For understanding the effect of SST on the moisture distribution, lamellar structure and molecular weight of wheat starch, the low-field nuclear magnetic resonance (LF-NMR), small angle X-ray scattering (SAXS) and size exclusion chromatography were employed. Compared with native starch, SST reduced the average thickness of crystalline layer and induced the depolymerization of starch molecules, which were attributed to the limited moisture transfer resulting in the partial gelatinization of starch granules. The structural variations had a synergistic effect on the rheological properties of starch samples. Upon SST, treated samples exhibited a weaker pseudoplasticity behavior and increased the deformability and mobility of gels systems. Furthermore, the lower tanδ values of treated starch samples were observed, indicating that the gels systems tended to the solid-like behaviors.

Effects of wheat protein on the formation and structural properties of starch-lipid complexes in real noodles incorporated with fatty acids of varying chain lengths

In this study, the effect of proteins (10%, w/w) on the formation of starch-lipid complexes (measured by Rapid Visco Analyzer (RVA)) in pure starch and noodles supplemented with different fatty acids (such as, lauric acid (LA), glycerol monolaurate (GML), stearic acid (SA), and glycerol monostearate (GMS), 3% w/w), in addition to their impacts on in vitro enzymatic digestion were assessed. The addition of protein and lipids increased the viscoelastic properties of wheat starch (WS) samples. The V-type diffraction intensity of WS-lipid sample mixed with protein was increased compared to WS-lipid samples without protein. Noodles enriched with fatty acids (particularly LA) showed higher relative crystallinity and enzyme resistant starch (ERS) compared to noodles without fatty acid incorporation. As shown by microscopic computed tomography (mCT), the crystalline pattern of noodles supplemented with LA and GML displayed a higher density than those incorporated with SA and GMS; the findings which are in line with thermal resistance and X-ray diffraction analysis. In sum, this study could foster a better understanding of the interplay between biomolecules during processing.

Effect of moist and dry-heat treatment processes on the structure, physicochemical properties, and in vitro digestibility of wheat starch-lauric acid complexes

Herein, we investigated the impact of moist (steaming and boiling) and dry (baking and microwaving)-heat treatment processes on the structure and physicochemical properties of wheat starch (WS) supplemented with lauric acid (LA). Elemental composition analysis revealed the interplay between WS and LA. Scanning electron microscopy (SEM) and iodine staining revealed that lamellar crystalline structure of WS-LA complexes was improved after moist-heat treatment (relative to samples without any heat treatments); the finding which is at variance to dry-heat treatment process. Additionally, high resistance to thermal decomposition and a lower 1022/995 cm−1 absorbance ratio were observed in moist-heat treated WS-LA compared with dry-heat samples. Moreover, the V-type diffraction peak intensity and resistance to in vitro enzymatic hydrolysis of samples treated with moist-heat were increased to a greater extent than the dry-heat treated counterparts. In sum, this study would facilitate the application of functional starch-lipid complexes in food necessitated heat treatments.

Pasting, gelatinization, and rheological properties of wheat starch in the presence of sucrose and gluten

The effect of starch/sucrose/gluten interactions on the thermal and rheological behavior of starch–gluten slurries was analyzed. Starch:gluten mixtures were dispersed in water and in a sucrose 50% (w/w) solution. The presence of sucrose significantly modified the pasting profiles of starch. Starch and starch:gluten slurries in sucrose solution showed a continuous increase of viscosity with the temperature rise, in contrast to samples in water, which presented the typical curve shape for starch. A decrease of starch viscosity during pasting was observed with increasing gluten proportion. The onset temperature of starch gelatinization was substantially increased with the addition of sucrose. Gluten addition slightly increased the gelatinization onset temperature in water, but not in sucrose solution. The presence of sucrose caused liquid-like viscoelastic properties of the starch gels, compared to gels made in water. Gluten addition decreased the gel viscoelastic properties in samples dispersed in water and sucrose solution. New particles populations were distinguished in gel samples with gluten. These results are an important basis to understand the effect of flour’s main components on the behavior of sugar-rich batter systems.

Studies on functional properties of wheat starch in the presence of Lepidium perfoliatum and Alyssum homolocarpum seed gums.

This study was performed to investigate the influence of Lepidium perfoliatum seed gum (LPSG) and Alyssum homolocarpum seed gum (AHSG) on functional properties of wheat starch. Various concentrations of gums (0.25%, 0.5%, 0.75%, and 1% dry starch weight basis) were added to wheat starch, and their influences on water absorption, pasting properties, gel strength, freeze-thaw stability and color parameters were investigated. The results showed that both gums improved water absorption, freeze-thaw stability, pasting parameters, gel hardness, gumminess, and chewiness whereas springiness was not affected and cohesiveness was decreased by the incorporation of gums and LPSG more effective than AHSG. Color parameters were also affected by the concentration of gums. The L value decreased whereas a value and b value increased in the presence of both gums. However, the changes were more obvious in samples containing LPSG. PRACTICAL APPLICATION: Starch is one of the most important carbohydrate materials in the food industry. However, native starch has shortcomings, such as sensitivity to shear or syneresis that limit its applications in food processing. Incorporation of hydrocolloids is an effective strategy to improve functional properties of starch. LPSG and AHSG are two novel sources of hydrocolloids which can be used to modify the properties of starch in food products.

Use of Amylomaltase to Steer the Functional and Nutritional Properties of Wheat Starch.

The fine molecular structure of starch governs its functionality and digestibility, and enzymatic approaches can be utilized to tailor its properties. The aim of this study was to investigate the in situ modification of starch by amylomaltase (AMM) from Thermus thermophilus in model starch systems subjected to hydrothermal treatments under standardized conditions and the relationship between molecular structure, rheological properties and in vitro digestibility. When low dosages of AMM were added to a wheat starch suspension prior to submitting it to a temperature-time profile in a Rapid Visco Analyzer, the increased peak viscosity observed was attributed to partial depolymerization of amylose, which facilitated starch swelling and viscosity development. At higher dosages, the effect was smaller. The low cold paste viscosity as a result of the activity of AMM reflected substantial amylose depolymerization. At the same time, amylopectin chains were substantially elongated. The longer amylopectin chains were positively correlated (R2 = 0.96) with the melting enthalpies of retrograded starches, which, in turn, were negatively correlated with the extent (R2 = 0.92) and rate (R2 = 0.79) of in vitro digestion. It was concluded that AMM has the potential to be used to deliver novel starch functionalities and enhance its nutritional properties.

Dry heating treatment: A potential tool to improve the wheat starch properties for 3D food printing application

The futuristic technology of three-dimensional (3D) printing is an additive manufacturing that allows obtaining creative and personalized food products. In this context, the study of food formulations (named as “inks”) to be processed through 3D printing is necessary. This work investigated the use of dry heating treatment (DHT), a simple and safe method, to improve the wheat starch properties aiming to produce hydrogels to be used as “inks” for 3D printing. Wheat starch was processed by dry heating for 2 (DHT_2h) and 4 h (DHT_4h) at 130 °C. Modified wheat starches showed an increase in granule size, but processing did not alter the granule’s shape nor surface, neither alter the molecular functional groups. On the other hand, DHT promoted slight molecular depolymerization, and reduction of starch crystallinity. Hydrogels “inks” based on the modified starches showed lower peak apparent viscosity during pasting, higher structural strength at rest, higher resistance to external stresses, higher gel firmness, and lower syneresis than hydrogels based on native starch. The hydrogels based on starch DHT_4h showed the best printability (greater ability to make a 3D-object by layer-by-layer deposition and to support its structure once printed) and this “ink” showed better reproducibility. Another point observed is that DHT extended the texture possibilities of printed samples based on wheat starch hydrogels. These results suggested that DHT is a relevant process to improve the properties of hydrogels based on wheat starch, making this ink suitable for 3D printing application.

Multiscale structural changes and retrogradation effects of addition of sodium alginate to fermented and native wheat starch

This work investigated the changes in multi-scale structure and retrogradation properties of native wheat starches (NS) modified by sodium alginate (AG) with and without fermentation. AG adhered on the surface of NS granules and fermentation promoted the adhesions. Compared with the addition of AG alone, dual modification by fermentation and AG together showed a greater effect to increase the weight-average molecular weight and reduce the relative crystallinity and double helix degree of NS. Small angle X-ray diffraction results showed a significant increase in amorphous region with dual modification compared with AG alone. Additionally, dual modification greatly slowed the increase of relative crystallinity and the enthalpy (ΔH) of NS paste during storage. The results of this study suggest that dual modification is a more effective approach to modify structures and properties of wheat starch than single AG treatment, and suggest its potential industrial application in starch-based foods.

Effects of low temperature at stem elongation stage on the development, morphology, and physicochemical properties of wheat starch

The low temperature in spring is a meteorological problem in wheat production because it leads to yield reduction and alteration of wheat quality. In this study, an artificial low-temperature treatment (LTT) at the stem elongation stage was implemented to investigate the starch granule development and physical and chemical properties of wheat starch. Results showed that the agronomic traits of spike, such as spike length, spikelet number per spike, and grain number per spikelet, decreased after LTT. LTT promoted the development of starch granules in developing grains at 15 days post-anthesis, resulting in increased B-type granules and reduced C-type granules with an irregular shape in mature grains. The swelling power of the starch granules was reduced, but their solubility was enhanced by LTT. The proportion of the amorphous structure within the granules increased, but the crystalline component decreased after LTT, leading to a significant reduction in the relative degree of crystallinity and double- and single-helix structures. Three types of hydrolysis showed that starch in LTT was easy to hydrolyze, resulting in a high degree of hydrolysis. The findings suggest that low temperature at the stem elongation stage can not only reduce the yield parameters of spike but also alter starch accumulation, thereby affecting the processability and structure characteristics of starch in wheat grains.