Gelatinization Of Wheat Starch Research Articles

Integrative experimental and computational analysis of the impact of KGM's polymerization degree on wheat starch's pasting and retrogradation characteristics

This study investigated the influence of Konjac Glucomannan (KGM) with varying degrees of polymerization (DKGMx) on the gelatinization and retrogradation characteristics of wheat starch, providing new insights into starch-polysaccharide interactions. This research uniquely focuses on the effects of DKGMx, utilizing multidisciplinary approaches including Rapid Visco Analysis (RVA), Differential Scanning Calorimetry (DSC), rheological testing, Low-Field Nuclear Magnetic Resonance (LF-NMR), and molecular simulations to assess the effects of DKGMx on gelatinization temperature, viscosity, structural changes post-retrogradation, and molecular interactions. Our findings revealed that higher degrees of polymerization (DP) of DKGMx significantly enhanced starch's pasting viscosity and stability, whereas lower DP reduced viscosity and interfered with retrogradation. High DP DKGMx promoted retrogradation by modifying moisture distribution. Molecular simulations revealed the interplay between low DP DKGMx and starch molecules. These interactions, characterized by increased hydrogen bonds and tighter binding to more starch chains, inhibited starch molecular rearrangement. Specifically, low DP DKGMx established a dense hydrogen bond network with starch, significantly restricting molecular mobility and rearrangement. This study provides new insights into the role of the DP of DKGMx in modulating wheat starch's properties, offering valuable implications for the functional improvement of starch-based foods and advancing starch science.

Preparation and characterization of carboxymethylated Anemarrhena asphodeloides polysaccharide and its effect on the gelatinization of wheat starch

In this study, a carboxymethylated Anemarrhena asphodeloides polysaccharide (CM-AARP) with an molecular weight (Mw) of 7.8 × 104 Da was obtained. CM-AARP was composed of four monosaccharides including d-mannose, d-glucose, d-galactose, and l-arabinose. Nuclear magnetic resonance (NMR) spectra revealed that the skeleton of CM-AARP was identical to that of AARP. Compared with AARP, CM-AARP had a superior inhibition effect on the gelatinization of wheat starch (WS) under the same condition. The addition of CM-AARP and AARP at 12 % enhanced the gelatinization temperature (60.47 ± 1.30 °C) of WS to 73.88 ± 0.49 °C and 69.75 ± 0.52 °C, respectively. CM-AARP could maintain the crystal structure of WS during gelatinization, the relative crystallinity with the 12 % CM-AARP addition was determined as 29.18 % ± 1.49 %, exceeding that of pure WS at 21.96 % ± 0.66 %. Moreover, CM-AARP influenced the rheological behavior of the gelatinized WS by reducing the viscosity and improving the fluidity. The results suggested that CM-AARP played an essential role in starch gelatinization and was a potential stabilizer in the starch-based food industry.

Genome-wide association study identifies loci and candidate genes for RVA parameters in wheat (Triticum aestivum L.).

The gelatinization and retrogradation characteristics of wheat starch affect the eating quality of Chinese-style food. Rapid Visco Analyzer (RVA) parameters have been widely used as important indicators to evaluate and improve the quality of wheat starch. However, the genetic basis of RVA parameters remains to be further explored. In the present study, a natural population was genotyped using 90K single nucleotide polymorphism (SNP) arrays, and the RVA parameters of this population grown in five environments were evaluated. The results showed that 22,068 high-quality SNP markers were identified and distributed unequally on the chromosomes. According to the genetic distance, 214 wheat materials were divided into four groups. Except for the pasting temperature (PTT), six parameters followed a normal distribution. Based on the general linear model, 969 significant association SNPs were detected by genome-wide association studies (GWAS), and chromosomes 7A and 2B had the most associated SNPs. Breakdown viscosity (BV) was associated with the most SNPs (n = 238), followed by PTT (n = 186), peak viscosity (PV; n = 156), trough viscosity (TV; n = 127), and final viscosity (FV; n = 126). According to the average linkage disequilibrium (LD), 33 stable quantitative trait loci (QTLs) were identified for single parameters in multiple environments, of which 12 were associated with BV, followed by peak time (PT; n = 8) and PTT (n = 7). On the other hand, 67 pleiotropic QTLs were identified for multiple parameters. Three candidate genes-TasbeIIa, TasbeI, and TassIIa-were screened for phenotyping analysis. The grain width and the weight of the TasbeIIa and TaSSIIa knockout (KO) lines were significantly lower than those of the TasbeI KO lines and the control (CK). The KO lines had smaller endosperm cells, smaller A-type starch granules, and higher amylose content. The TasbeI KO lines showed normal RVA curves, while the TasbeIIa KO lines showed flat curves. However, the TaSSIIa lines failed to paste under the RVA temperatures. Conclusively, the SNPs/QTLs significantly associated with the RVA parameters and genetic resources with novel haplotypes could be used to improve the quality of wheat starch.

Analysis of the impact of drying on common wheat quality and safety

Mycotoxin contamination in grain has been an ongoing concern in the world. Wheat, as a staple crop in China, is particularly notable for its mycotoxin contamination. The main mycotoxins in wheat include deoxynivalenol (DON) and its derivates, zearalenone (ZEN) and aflatoxin B1 (AFB1). After harvest, drying process is an effective technique and a necessary step to ensure the long-term safe storage of wheat. In this study, the moisture content, the concentrations of total fungi and main mycotoxins in post-harvest wheat of three wheat growing areas in the North China Plain were examined, and the effect of different drying methods on wheat quality was evaluated. The results showed that 87.5% of wheat samples were simultaneously contaminated with two or more mycotoxins. Due to the pre-harvest heavy rainfall, the moisture content, the levels of total fungi and mycotoxins in wheat samples of Liaocheng city were significantly higher compared to other regions. Moreover, the effects of different drying methods on the starch gelatinization and viscosity properties of wheat were investigated. The results showed that both natural air drying and dryer drying altered the crystal structure within starch particles and affected the gelatinization and viscosity properties of wheat starch. However, there is no significant difference between the wheat samples treated with two drying methods.

Study on the gelatinization and digestive characteristics of wheat starch and potato starch under low moisture conditions

This study explored the gelatinization and digestive characteristics of wheat and potato starches under low moisture conditions using identical processing parameters. The results revealed that potato starch exhibited greater resistance to digestion than wheat starch, with an enzyme hydrolysis rate 18 % to 30 % lower than wheat starch under the same conditions. The analysis of particle size, swelling power, and low-field NMR demonstrated that potato starch required almost 40 % more moisture for full gelatinization than wheat starch, indicating that low-moisture conditions could not meet the significant water demand of potato starch. Additionally, the DSC analysis showed that potato starch had superior thermal stability, with To of 62.13 °C and ΔH of 16.30 (J/g). Subsequently, the microscopy results showed that the partially gelatinized wheat starch had a rough, porous surface, allowing enzymes for direct access to hydrolysis. In contrast, the potato starch had smoother and less damaged particles without visible pores, enzymes had to degrade it progressively, layer by layer. Furthermore, potato starch still exhibited a lower enzyme hydrolysis rate than wheat starch under the same gelatinization levels. Overall, potato starch is more resistant to hydrolysis and gelatinization in low-moisture environments, making potato starch suitable for low-digestibility products like potato biscuits or chips.

Purple rice starch in wheat: Effect on retrogradation dependent on addition amount

While individual starch types may not possess the ideal gelatinization and retrogradation properties for specific applications, the amalgamation of multiple starch varieties might bestow desirable physicochemical properties upon resulting starch-based products. This study explored the impact of incorporating purple rice starch (PRS), as a novel starch variant (up to 15 % PRS), on the gelatinization and retrogradation (within 14 days) of regular wheat starch (WS). Rheological and texture assessments demonstrated that the introduction of PRS diminished the viscoelasticity and hardness of fresh WS paste. Additionally, in the case of retrograded WS pastes stored at 4 °C for 1–14 days, the incorporation of 10 % or 15 % PRS effectively retarded the reduction in transparency and significantly reduced hardness, retrogradation degree, the ratio of absorbance at 1047/1017 cm−1, and relative crystallinity. Notably, 10 % PRS results in a more pronounced effect. Conversely, 5 % PRS induced an opposing impact on retrograded WS post-storage. Moreover, scanning electron microscopy revealed that as the proportion of PRS increased, the microstructure of gelatinized WS-PRS closely resembled that of pure PRS. In conclusion, the diverse effects of varying PRS proportions on WS alter the texture and characteristics of starch-based foods, underscoring the potential of starch blending for improved applications.

The influence of short-range molecular order in gelatinized starch on the formation of starch-lauric acid complexes

A model system of gelatinized wheat starch (GWS) and lauric acid (LA) was used to examine the effect of residual short-range molecular order in GWS on the formation of starch-lipid complexes. The extent of residual short-range molecular order, as determined by Raman spectroscopy, decreased with increasing water content or heating duration of gelatinization. The enthalpy changes, crystallinity, short-range molecular order and the in vitro enzymic digestion of GWS-LA complexes increased initially to a maximum and then declined as the short-range molecular order in GWS decreased, showing that there was an optimal amount of residual short-range molecular order in GWS for maximizing GWS-LA complexes formation. Below this optimum amount, the limited disruption of short-range molecular order may constrain the mobility of amylose chains for complexation with LA, whereas with excessive disruption above this amount the amylose chains may be too disorganized or entangled to form complexes with LA. The susceptibility of GWS-LA complexes to enzymatic hydrolysis was influenced by both long- and short-range structural order, and to a lesser extent the amounts of complexes. This study showed clearly the role of short-range molecular order in gelatinized starch in influencing the formation of GWS-LA complexes.

Effect of heat-moisture treatment of wheat (Triticum aestivum L.) grain on micronutrient content of flour, and noodles and bread qualities

The effects of heat-moisture treatment (HMT) of wheat grain on the contents of vitamins and minerals in wheat flour were analyzed to explore the functions of HMT of wheat grain in enhancing the micronutrient content of its flour. In addition, the gelatinization and thermomechanical properties of wheat flour and qualities of noodles and bread were studied. The results demonstrated that HMT of wheat grain at 65, 80, and 95 °C could significantly improve the contents of vitamins or minerals in wheat flour. HMT at 95 °C resulted in a slight gelatinization of wheat starch and weakening of gluten; however, at 50 and 65 °C, dough stability improved. HMT at 50 and 65 °C improved the qualities of noodles and bread, whereas they worsened at 95 °C. Therefore, HMT at 65 and 80 °C can improve the content of vitamins and minerals without significantly effecting noodles and bread qualities.

Fish collagen peptides, an effective starch gelatinization regulator, modify the processing properties and improve the nutritional value of wheat starch

Owing to diverse functional and bioactive properties, fish collagen peptides (FCP), a by-product from the fish processing industry, have garnered popularity among consumers. The primary objective of this study is to investigate the impact of FCP on wheat starch (WS) gelatinization and evaluate its application potential in starchy food. Pasting and thermal analyses indicated the degree of starch gelatinization decreased linearly as the concentration of FCP increased. Under the peptide concentration, the peak viscosity and enthalpy change were reduced by 76.54% and 26.23%, respectively. FCP competed with WS for available water, resulting in the preservation of more intact starch granules after gelatinization. Rheological results suggested that FCP reduced the viscosity and weakened the gel structure of starch pastes. With decreased tanδ, starch pastes presented a more dominant elastic behavior. Moreover, FCP alleviated the digestion rate of WS, with the rapidly digestible starch content decreasing from 79.94% to 73.19% and the resistant starch content increasing from 11.67% to 17.06%. Fourier transform infrared spectroscopy and X-ray diffraction analysis demonstrated that FCP improved the ordered structures of WS and hydrogen bonds played a pivotal role in the property changes of starch. Consequently, it is inferred that FCP holds considerable promise as a starch gelatinization regulator, which is capable of modifying the processing properties and enhancing the nutritional value of starchy food.

Effects of Salecan on the gelatinization and retrogradation behaviors of wheat starch

The retrogradation behavior of native wheat starch (WS) is undesirable for starchy food. Adding polysaccharides is a secure and effective method to improve starch properties. Herein, the effects of Salecan, a novel microbial polysaccharide, on WS's gelatinization and retrogradation behaviors were investigated. Results showed that Salecan increased peak, trough, and final viscosities while decreasing WS paste's breakdown and setback values, suggesting Salecan inhibited the short-term retrogradation of WS. The rheological results showed Salecan increased the viscosities of the gelatinized samples, and its storage moduli decreased initially and then increased when Salecan was added more than 10 g/kg. Moreover, Salecan significantly reduced the WS gel hardness during long-term storage. SEM and XRD results showed Salecan improved the microstructure and reduced the crystallinities of retrogradation WS gels, respectively. Furthermore, the application of Salecan in Chinese steamed bread showed Salecan could inhibit moisture migration and maintain the texture of prepared bread during chilled storage, demonstrated by LF-NMR and TPA, respectively. In summary, Salecan could inhibit the retrogradation of WS, and the recommended optimal added level is 10 g/kg of WS weight, which would be helpful for the development of starchy food with a longer shelf-life.

Hydrocolloids-aided control of oil penetration and distribution in deep-fried breaded fish nuggets

To investigate the effect of hydrocolloids on oil penetration and distribution in fried batter-breaded fish nuggets (BBFNs), sodium carboxymethyl cellulose (CMC-Na), guar gum (GG), and xanthan gum (XG) were individually blended (0.2 or 0.3%, w/w) into the mixture (1:1, w/w) of wheat gluten (WG) and wheat starch (WS) to form batters. The moisture absorption capacity of XG was found to be the highest, followed by CMC-Na, GG, WG, and WS. Hydrocolloids increased the batter viscosity, shear modulus, WS gelatinization and WG denaturation temperatures, BBFNs pick-up, thermogravimetry temperature, and the bound water content in crust. This trend was opposite with enthalpy change (ΔH) during starch gelatinization and protein denaturation, both of which lessened pores and cracks, leading to an inhibition of oil penetration into fried BBFNs. Of the three hydrocolloids, XG exhibited the greatest effect, followed by CMC-Na and GG. Therefore, XG was suitable for reducing fat content of fried BBFNs. Overall, the hydrophilic and thickening capabilities of the three studied hydrocolloids and their interactions with WS and WG altered the batter characteristics and reinforced the thermal stability of the crust, thereby reducing oil penetration and distribution in deep-fried BBFNs. This work will not only provide new ideas to clarify oil penetration based on hydrocolloids for fried BBFNs, but also provide scientific instructions for the large-scale production of low-fat fried batter-breaded foods.

Effect of Climatic Conditions on Wheat Starch Granule Size Distribution, Gelatinization and Flour Pasting Properties

The aim of this study was to determine the effects of different varieties, year and location of growing, and their interactions, on wheat starch and flour properties, and to analyze the relationship between these attributes. The set of 92 wheat samples chosen to cover wide ranges in the parameters commonly used for the assessment of wheat flour and starch properties was reduced to a representative set of 27 samples. The obtained results showed that wheat variety and year significantly affected maximum viscosity (MV), alpha–amylase activity (AA), amylose content (AM), volume proportion of A-, B- and C-starch granules, as well as gelatinization temperatures, while the year and location by year interaction had a significant effect on the falling number (FN). In this work, a number of significant correlations were observed among analyzed starch and flour properties. AA was mostly influenced by the changes in packing of starch granules and granule size distribution, while gelatinization temperatures were affected by particle size distribution. Additionally, when testing the suitability of the parameters for the estimation of alpha–amylase activity, it was determined that Amylograph was more reliable in predicting alpha–amylase than FN because it provided a better description of the state of flour starch complex.

澱粉補強リン酸カルシウム骨ペーストへの異種カチオン種の導入

Bone cement is applied to bone detect caused by injury and disease. Our group has developed a novel bone paste by kneading a gelatinized wheat starch and calcium phosphate (CP) powders in which CaHPO4, Ca4(PO4)2O and β-Ca3(PO4)2 are equimolarly mixed. This bone paste is easily handled and can be set to form hydroxyapatite (HAp) under physiological conditions. On the other hand, previous literature reported that strontium ion can promote and regulate the activity of osteoblastic and osteoclastic cells in the living bone, respectively. In addition, copper ion is reported antibacterial performance. In this work, strontium and copper ions were fed into the bone paste as starting materials to promote cell activity as well as antibacterial properties. Paste samples were prepared by kneading a starch gelatinized with mixed powders of CP, α-SrHPO4 and Cu2+-substituted β-Ca3(PO4)2. Phase change, release behavior of metal cations and antibacterial properties were investigated. A paste sample immersed in Tris-buffered NaCl solution was set through forming HAp, and the amount of strontium ion released from the paste sample was a level expected to enhance the cell activity. However, all the pastes didn’t show antibacterial properties in spite of introducing of copper ion to the samples.

Inhibition of In Vitro Amylolysis of Wheat Starch by Gluten Peptides.

The effect of gluten peptides (GPs) isolated from a gluten proteolysate on in vitro amylolysis of gelatinized wheat starch was investigated. GPs in a pepsin hydrolysate were fractionated into fractions with molecular weights (MWs) of 500-3000, 3500-7000, 10-17, and 35-48 kDa. The fractions containing peptides with MW > 10 kDa had a strong inhibitory effect on enzyme activity and amylolysis of starch, whereas GPs with MW <10 kDa had no inhibitory effect. Binding constants estimated by surface plasmon resonance showed that peptides in the fractions with MW > 10 kDa bound more strongly to α-amylase, in contrast to peptides of MW <10 kDa. Significant correlations were observed between digestion parameters and equilibrium binding affinity. We conclude that peptides with MW >10 kDa in a pepsin digest of gluten have a strong inhibitory effect on in vitro enzymatic hydrolysis of starch due to their strong binding affinity to α-amylase.

The thermal dependence of the protein-sparing effect in rainbow trout (Oncorhynchus mykiss, Walbaum 1792).

The authors performed an instantaneous bioenergetic study with rainbow trout (Oncorhynchus mykiss) of 206.3 g ± 2.9 g in a group respirometer of nine 250 l tanks at five different water temperatures (12, 14, 16, 18, 20°C) to determine the optimal thermal condition for a maximal visualization of the protein-sparing effect. Twelve fish per tank were tested at a stocking density of 9.94 kg m-3 ± 0.14 kg m-3 and fed three low-protein/high-energy diets with constant crude protein content of c. 35% and three different energy contents (17.35, 18.76, 20.50 MJ kg-1 ) once daily at a ration of 1.3% body weight (n = 3). Energy levels were increased by adding gelatinized wheat starch as a carbohydrate source and fish oil, canola oil and palmitin as lipid sources. Three different dietary digestible protein/digestible energy ratios (DP/DE: 20.38, 19.08, 18.09 mg kJ-1 ) were achieved by replacing bentonite as a non-nutritive filler with carbohydrates and lipids. Oxygen consumption and ammonia excretion were assessed to obtain the potentially retainable energy (RE) and ammonia quotient (AQ) as benchmarks for potential growth and protein-sparing effect. The results showed the lowest relative metabolic combustion of protein at 16.9°C ± 0.1°C. The authors determined this temperature to set the optimal thermal condition for the induction of a maximum protein-sparing effect in juvenile rainbow trout. Increasing the DP/DE ratio significantly altered the magnitude of the relative metabolic protein use but had no effect on its interactions with temperature. The authors were able to reduce average metabolic fuel use of protein across diets from 16.2% ± 2.3% at 12°C to 8.0% ± 1.2% at 16°C. This study found no relevant significant differences of RE with the environmental temperature.

Starch and Dough-Related Properties of Wheat (Triticum aestivum L.) Exposed to Varying Temperatures and Radiances after Anthesis

With the increase in global warming and solar radiation, the starch quality and dough properties of wheat have also been affected to some negative extent. To prepare for the effects of future climate change, we explored the effects of different temperatures and radiation on the properties of wheat starch and dough. Six sowing dates for four wheat varieties were selected for this study. The seedling population on the first sowing date (S1) was 300 × 104 plants ha−1, which increased by approximately 10% after the subsequent sowing date. The results showed that a delay in sowing time increased the daily mean temperature after anthesis and decreased the effective accumulated temperature and cumulative solar radiation. When the daily mean temperature increased 0.32 °C after anthesis, the total starch content decreased 1.2%, the sedimentation value increased by 14.19 s, the water absorption increased 0.62%, the dough development time increased 0.4 min, and the dough stability time increased 0.28 min. The gelatinization and dough properties of wheat starch were not only related to the daily mean temperature, but were also significantly related to the effective accumulated temperature and cumulative solar radiation. The results showed that the starch and dough properties of wheat are also related to the cumulative radiation temperature after anthesis. Compared with radiation, temperature is the main climatic factor affecting the formation of wheat starch and dough.

Mechanisms of the different effects of sucrose, glucose, fructose, and a glucose-fructose mixture on wheat starch gelatinization, pasting, and retrogradation.

The gelatinization, pasting, and retrogradation of starch influence texture, quality, and shelf-life attributes of many foods. The purpose of this work was to document the effects of a 50:50 glucose:fructose (glc:fru) mixture and sucrose solutions on these starch traits to provide a fundamental basis to explain the different texture and shelf-life attributes of baked goods formulated with these sugars. Differential scanning calorimetry, rapid visco analyzer, and oscillatory rheometry were used to quantify the effects of glucose, fructose, glc:fru mixture, and sucrose at different concentrations (0% to 60% w/w), on the gelatinization temperature, pasting, and retrogradation properties of wheat starch. Distinct differences were found between the effects of sucrose and those of the monosaccharides including the glc:fru mixture. Sucrose elevated Tgel and pasting temperature most and decreased other RVA parameters compared to the monosaccharides as concentration increased. Fructose and the glc:fru mixture promoted amylopectin retrogradation, while retrogradation was inhibited in sucrose and glucose solutions. The glc:fru mixture had similar effects on starch properties compared to fructose under static measurement conditions (DSC), and the effects were in between those of glucose and fructose under dynamic conditions when shear was applied (RVA and rheology). These effects are explained by the phase separation and/or solute partitioning of the monosaccharide constituents of the glc:fru mixture. Sugar solution physicochemical properties correlated strongly with starch gelatinization and retrogradation. The results substantiate the important relationship between sugar physicochemical properties and solution dynamics with starch thermal properties, which in turn affect the texture and structure of starch-containing food products. PRACTICAL APPLICATION: The quality attributes of starch-containing baked goods are influenced by how different amounts and types of sugars affect starch cooking properties. The underlying mechanisms of the different sugar effects involve solution viscosity, intermolecular hydrogen bonding, and phase separation. Substituting one sugar for another has less effect on these starch properties in products with lower sugar concentrations than in products with more sugar. Mixtures of sugars behave differently than single sugars in different conditions due to phase separation. Baked goods made with glucose:fructose mixtures in place of sucrose likely have higher amounts of gelatinized starch and increased firmness (i.e., staling or retrogradation) over time.

Extraction, purification, structural characterization of Anemarrhena asphodeloides polysaccharide and its effect on gelatinization and digestion of wheat starch

Pressurized water extraction (PWE) of the polysaccharides from Anemarrhena asphodeloides rhizomes was optimized by the response surface method (RSM). The high yield of 34.82 ± 0.38% was gained under the optimal conditions of material to liquid ratio 42 mL/g, pressure 6.4 MPa, extraction temperature 51 °C, and extraction time 15.3 min. An Anemarrhena asphodeloides rhizome polysaccharide (AARP) was obtained after purifying by D4006 macroporous resin and Sephadex G-100 column. High-performance liquid chromatography (HPLC) analysis showed that AARP with the molecular weight of 5100 Da consisted of four monosaccharides including mannose, glucose, galactose, and arabinose. 1D and 2D NMR analyses confirmed that the backbone of AARP was comprised of →4)-β- D -Man p -(1→, →4)-β- D -Glc p -(1→, β- L -Ara f -(1→, →2)-β- D -Man p -(1→, and →3)-α- D -Gal p -(1→ residues. In addition, AARP exhibited the property of inhibiting the pasting and in vitro digestion of wheat starch. These findings laid the foundations for AARP as an additive in regulating starch foods. • Pressurized water extraction was an efficient method to extract Anemarrhena asphodeloides polysaccharide. • A new neutral polysaccharide (AARP) containing four monosaccharides was obtained. • The primary structure of AARP was determined by Chemical methods and instrument analysis. • AARP could effectively inhibit the pasting and in vitro digestion of wheat starch.

Genetic dissection of quantitative traits loci identifies new genes for gelatinization parameters of starch and amylose-lipid complex (Resistant starch 5) in bread wheat

Starch is a major component of cereal grains such as wheat. Physicochemical and functional properties of starch affect end-use food quality and nutrients. To improve cultivars that preserve superior starch quality, the genetic foundation of the wheat starch and amylose-lipid complex (ALc, Resistant starch type 5) gelatinization are needed. This genome-wide association (GWA) mapping used 192 wheat genotypes (previously reported) to generate SNPs using an enhanced version of sequencing termed ddRAD on the Illumina Hi-seq X platform and 3696 high-quality influential SNPs were filtered out. The heterozygosity and Fst ranges in five subpopulations were 0.31–0.40 and 0.18–0.30 respectively. Nucleotide diversity and PIC ranged from 0.21 (6A) to 0.32 (2A) and 0.29 (6A) to 0.39 (4D) respectively. The Shannon waiver index was 1.7 and the whole-genome LD decay was 22 Mb at r2 = 0.38. Following FDR, 23 and 8 SNPs showed association with starch properties in the year 2017 and 2018, respectively while 93 and 20 SNPs were associated with ALc gelatinization in the year 2017 and 2018 respectively. The identified potential new genes (GSK3-alpha, RING-type domain-containing protein, Tetratricopeptide repeat, Hexosyltransferase, GLP, SNF1, and WRKY transcription factor) within LD range (∼16 Kb to ∼15 Mb), BLUP value, and cis and trans-position of SNPs network provide valuable information for the future wheat breeding strategy for the improvement of the starch quality trait.

Effect of wheat bran arabinoxylan on the gelatinization and long-term retrogradation behavior of wheat starch

The effect of wheat bran arabinoxylan (WBAX) with different molecular characteristics on the gelatinization and long-term retrogradation behavior of wheat starch (WS) have been evaluated. WBAXs with Mw of 280–754 kDa and Ara/Xyl of 0.45–0.62 were obtained through alkaline extraction with graded ethanol precipitation. WBAXs with larger Mw and branching degree could impede gelatinization process of wheat starch by effectively decreasing the water availability for starch gelatinization. The hydrogen-bonding interactions between WS and WBAX could enhance the gel strength of WS-WBAX mixed pastes. WBAXs with lower branching degree could inhibit the long-term retrogradation of starch through hindering the rearrangement of amylopectin and double-helical associations of amylose during long-term storage, due to hydrogen-bonding interaction between WBAX and starch. Low-field nuclear magnetic resonance (LF-NMR) relaxometry analysis confirmed that the addition of WBAXs could improve the water holding properties of retrograded starch gels.