Viscosity Of Starch Research Articles

Assessment of the Characteristics of Waxy Rice Mutants Generated by CRISPR/Cas9.

The cooking and eating quality of rice grains is a major focus from a consumer’s perspective and is mainly determined by the apparent amylose content (AAC) of the starch. Waxy rice, a type of rice with an AAC of less than 2%, is an important goal for the breeding of high-quality rice. In recent years, the cloning of the Waxy (Wx) gene has revealed the molecular mechanism of the formation of waxy traits in rice. However, there have been limited studies on the physicochemical properties, such as gelatinization temperature, rapid viscosity analyzer profile, and amylopectin fine structure of wx mutants. In the current study, a rapid and highly efficient strategy was developed through the CRISPR/Cas9 gene-editing system for generating wx mutants in the background of five different rice varieties. The wx mutation significantly reduced the AAC and starch viscosity but did not affect the major agronomic traits (such as plant height, panicle number per plant, grain number per panicle, and seed-setting frequency). Incorporation of the wx mutation into varieties with low initial AAC levels resulted in further reduction in AAC, but without significantly affecting the original, desirable gelatinization traits and amylopectin structure types, suggesting that parents with low initial AAC should be preferred in breeding programs.

Development of a blue maize pinole: Optimization of functional ingredients by a D‐optimal mixture design approach

The effect of temperature and toasting time of blue maize was evaluated to develop and optimize a pinole mixture. For toasting, total anthocyanins (TA), polyphenols (TP), antioxidant activity (AA), color, viscosity, and microscopic analysis of starch were determined. With the best conditions, a pinole formulation was developed by adding amaranth, chickpea, chia, and oat through a D-optimal mixture design. High temperature and toasting time decreased the TA, TP, lightness, and viscosity; and increased the AA, color (a*, b*), and starch damage. Toasting at 200°C for 4.5 min was adequate, with TA, color (a*), and viscosity retention of 55.68%, 86.83%, and 81.11%, respectively. All four ingredients had significant effects and the special cubic model described the nutritional, physicochemical, functional, and rheological properties. Optimum pinole mixture (1.0% amaranth, 4.97% chickpea, 7.80% chia, and 4.63%) based on reaching the maximum contents of protein, fiber, AA, and TP, had better properties than a local blue maize pinole. Novelty impact statement This study informs about the importance of establishing the temperature and time conditions for toasting blue maize in order to obtain a base of toasted maize for the formulation of pinole with minimal losses of bioactive compounds and color, but with adequate physical and rheological properties. In addition, contributes to the development of a blue maize pinole with ingredients that improve its color, nutritional, rheological, and functional properties; representing an alternative of healthy consumption.

Partial replacement of starch‐based flours with quinoa or yellow lentil flour in the production of gluten‐free noodles

The aims of this study are to produce gluten-free noodles by partial replacement of starches with quinoa (QF) and yellow lentil flour (YLF) for improving the nutritional composition with plant-based gluten-free protein sources and evaluate the effects of enrichment levels (0-12.5-25-50%) on the quality and textural properties of noodles. The protein content of control noodles (C) was significantly increased due to QF and YLF replacement, however, the protein content of 50% YLF was found more than double of the control sample (p < .05). The peak viscosity of corn starch was the highest among flour samples (4.792 Pa s), whereas the lowest was obtained for QF (0.882 Pa s). Cooking loss of gluten-free noodles was increased by QF or YLF increased (p < .05), however, all noodles fell within acceptable limits. The hardness of gluten-free noodles was increased by QF and YLF amounts increased and reached the highest value of 50% YLF-including noodles. Novelty impact statement Sustainable food product development can be achieved by utilization of legumes due to their low carbon foodprint. They are good candidates for nutritional improvement as increasing quinoa and yellow lentil flour has significantly increased the protein content of noodles. Hardness of noodles was increased and reached a maximum of 50% YLF-added sample. Cooking loss of all noodles was found acceptable because they were lower than the given limits of durum-wheat pasta.

Effects of Betanin on Pasting, Rheology and Retrogradation Properties of Different Starches.

As a natural pigment with high antioxidative activity, betanin is underutilized owing to less attention. This study aimed to investigate the impact of betanin on pasting, rheology and retrogradation properties of rice, potato and pea starches. Betanin decreased the peak, trough and final viscosity of rice and potato starches, but increased those of pea starch. Rheology measurements implied that betanin had the greatest effect on the hysteresis loops and dynamic modulus of potato starch. Betanin endowed starch pastes with a vivid red appearance and maintained the color of the starch pastes during storage. XRD analysis indicated that betanin weakened the diffraction intensities and reduced the crystallinity of the retrograded starches. Meanwhile, betanin reduced the short-range ordered structure of the retrograde starches. The results of DSC analysis found that betanin significantly depressed the retrogradation enthalpy and retrogradation rate, implying that the long-term retrogradation of starches was delayed. Furthermore, the changed morphology of the retrograded starches was observed. These results suggested that betanin could be applied as an excellent colorant and inhibitor of retrogradation in foods such as bread and pastry products.

Effect of oil modification on the multiscale structure and gelatinization properties of crosslinked starch and their relationship with the texture and microstructure of surimi/starch composite gels

This work investigated the multiscale structure and gelatinization properties of different oil-modified crosslinked starches and their relationship with the texture and microstructure of surimi/starch composite gels. The results showed clusters were formed by the agglomeration of starch, with oil on the surface of granules. Oil modification did not damage the long-range crystalline structure but impaired the short-range ordered structure. A high oil modification degree was shown to weaken starch structure, in contrast to an adverse effect for a high crosslinking level. Furthermore, compared with crosslinked starches, Oil-CTS had lower pasting temperature and gelatinization enthalpy, a higher viscosity, and better gel-reinforcing effect. Correlation analysis revealed the texture of surimi/starch composite gels was negatively correlated with the helical structure and pasting temperature of starch, and positively correlated with final and setback viscosity of starch and the swollen size of starch granules in surimi gel.

Impact of Enzyme Modification on Physicochemical Properties of Oat Flake and Starch

AbstractOat flakes are modified with alpha (α)‐amylase and a combination of α‐amylase and cellulase (α‐amylase/cellulase) to determine the effect of enzyme modification on the quality of oat flakes and physicochemical properties of oat starch. Enzyme modification using α‐amylase and cellulase increases the water absorption capacity and decreases the hardness and adhesiveness of oat flakes by degrading long polysaccharide chains. The molecular weight of oat starch modified with α‐amylase and α‐amylase/cellulose is lower than that of native oat starch. Moreover, the depolymerization of starch molecules is more notable in starch modified with α‐amylase/cellulase than in starch modified with α‐amylase alone. α‐Amylase treatment during oat flake processing causes the loss of peak viscosity, while α‐amylase/cellulase treatment results in the loss of both peak and final viscosity of oat starch. In addition, enzyme modification with α‐amylase/cellulase reduces the content of amylose‐lipid complex. Solubility and swelling power are also significantly increased in α‐amylase/cellulase‐modified oat starch. These results indicate that the modification of oat flakes with α‐amylase and cellulase induces changes in starch structure, thereby affecting physicochemical properties of oat starch and quality of flakes.

3D printing properties and printability definition of Pennahiaargentata surimi and rice starch

Correlation of related factors (texture, gel strength, rheological properties) were analyzed for better characterize 3D material printability. Moreover, printability calculation formula also was established to represent material plasticity. Pennahia argentata surimi shown best plasticity with 78% moisture content and 20% rice starch respectively. Additionally, starch and carrageenan increased gel strength, yield stress of surimi and starch respectively, which brought better mechanical strength and supporting ability. They also affected viscosity of surimi (increasing) and starch (decreasing), which brought better fluidity and adhesion respectively, resulting in good printability, especially starch (8%)-surimi, carrageenan (0.5%)-starch. Based on their interaction relationships, 3D printability equation of printing inkswas established their relevance and corresponding unified values. To judge the printability of same materials under different conditions were consistent with real print results. These could provide methods for judging material printability by specific values and promote the application and spread of 3D materials.

Comparison of Regular and Selenium-Enriched Tortillas Produced from Sprouted Corn Kernels

Corn kernels were soaked with different selenium (Se) solutions (0, 12 or 24mg Na2SeO3/L), sprouted for different times and then lime-cooked for the pilot plant production of tortillas. The dough and tortillas were quantified in terms of total Se, starch and protein content. Also, in vitro digestibility, texture, color, and sensory properties were evaluated. Results indicated that lime-cooking times were significantly reduced from 39.15 to 14.34, 8.42 and 2.80min when whole corn was compared with kernels germinated for 1, 2 or 3days. The Se content of regular tortillas (0.08µg/g dw) increased about eight-fold in tortillas (0.651-0.625µg/g dw) produced of corn germinated for twoday and treated with 24mg of Na2SeO3/L. The highest α-amylase activity and lower starch viscosity values were observed in 3-day germinated supplemented with the highest Se. Se-enriched tortillas produced from 2-day sprouted kernels treated with 12mg Na2SeO3 showed the highest levels of general acceptability, texture and flavor.

Effect of Fermentation Time on Molecular Structure and Physicochemical Properties of Corn Ballast Starch.

The effect of fermentation treatment on the surface morphology, crystal structure, molecular weight, chain length distribution, and physicochemical properties of corn starch was investigated using natural fermentation of corn ballast. The amylose content in corn ballast starch reduced at first after natural fermentation, then grew, following the same trend as solubility. There were certain erosion marks on the surfaces of fermented corn ballast starch granules. The crystalline structure of corn ballast starch remained the same, i.e., a typical A-type crystalline structure, at different fermentation times; however, the intensities of diffraction peaks were different. The weight-average molecular weight of starch first increased and then decreased after fermentation. The content of low-molecular-weight starch (peak 3) decreased from 25.59 to 24.7% and then increased to 25.76%, while the content of high-molecular-weight starch (peak 1) increased from 51.45 to 53.26%, and then decreased to 52.52%. The fermentation time showed a negative correlation with the viscosity of starch, and the pasting temperature first increased, and then decreased. Natural fermentation can be used as a technical means to produce corn starch products as a result of the experiments' findings, and future experiments will detect and analyze the bacterial structure of corn fermentation broth in order to better understand the molecular mechanism of natural fermentation affecting the structure and physicochemical properties of corn starch.

Interrelating Grain Hardness Index of Wheat with Physicochemical and Structural Properties of Starch Extracted Therefrom.

To investigate the physicochemical, structural, and rheological characteristics of starch from wheat cultivars varying in grain hardness index employed in making jiuqu and to interrelate grain hardness index with physicochemical and structural properties of starch. Starch extracted therefrom was investigated for structural and physicochemical properties. Starch granules showed relatively wide granule size distribution; large size granules showed lenticular shapes while medium and small size granules exhibited spherical or irregular shapes. Starch from wheat with a lower grain hardness index exhibited a relatively higher degree of crystallinity. Chain-length profiles of amylopectin showed distinct differences; among the fractions of fa, fb1, fb2, and fb3 representing the weight-based chain-length proportions in amylopectin, the fa fractions ranged from 19.7% to 21.6%, the fb1 fractions ranged from 44.4% to 45.6%, the fb2 fractions ranged from 16.2% to 17.0%, and the fb3 fractions ranged from 16.1% to 18.8%, respectively. To, Tp, Tc, and ∆H of starch ranged from 57.8 to 59.7 °C, 61.9 to 64.2 °C, 67.4 to 69.8 °C, and 11.9 to 12.7 J/g, respectively. Peak viscosity, hot pasting viscosity, cool pasting viscosity, breakdown, and setback of starch ranged from 127 to 221 RVU, 77 to 106 RVU, 217 to 324 RVU, 44 to 116 RVU, and 137 to 218 RVU, respectively. Both G’ and G” increased in the frequency range of 0.628 to 125.6 rad/s; the wheat starch gels were more solid-like during the whole range of frequency sweep.

Effect of pulsed light treatment on the physicochemical properties of wheat flour and quality of fresh wet noodles

AbstractBackground and ObjectivesPulsed light (PL) was first applied to the production of low bacterial wheat flour—treating wheat kernels with PL. The effect of PL on the physicochemical properties of wheat flour and the quality of fresh wet noodles (FWN) were investigated.FindingsAfter treatment, the total plate count (TPC), yeast and mold count (YMC) in wheat flour decreased significantly. Wet gluten content and the stability time reached their maximums when the pulsed flash frequency was 10 c. Starch viscosity increased slightly, mainly due to an increase in damaged starch content. Secondary structures altered remarkably, which were consistent with changes in gluten protein microstructures. Moreover, the textural properties of FWN were improved greatly. Browning of FWN was significantly inhibited because of low polyphenol oxidase (PPO) activity in wheat flour.ConclusionPL was effective in decreasing the initial microorganisms in wheat flour as well as improving the quality of dough and FWN, and the optimum treatment was pulsed energy of 500 J, pulsed flash distance of 9 cm, and pulsed frequency of 10 c.Significance and NoveltyThese results showed that PL treatment could decrease TPC and YMC in wheat flour significantly, improve farinograph and pasting properties, change gluten protein microstructures and secondary structures, as well as improve textural properties of FWN and inhibit its darkening greatly, which provided a new method for low bacterial wheat flour production and promoted PL's industrialization.

Effect of Integrated Organic–Inorganic Amendments on Leaf Physiological and Grain Starch Viscosity (Rapid Visco-Analyzer Profile) Characteristics of Rice and Ultisols Soil Quality

Current farming systems are highly reliant on chemical fertilizers (CF), which negatively affect soil health, the environment, and crop productivity. Substituting organic fertilizer for chemical fertilizer (CF) is an important agricultural practice that improves soil health and crop productivity and is eco-friendly. To explore the effects of organic fertilizer in the form of cattle manure (CM) or poultry manure (PM) combined with CF on soil properties, leaf physiological traits, and grain physiochemical characteristics of rice, a 2-year field experiment was conducted in a dual cropping system with six treatments: Neg-CF (no N fertilizer control), Pos-CF (100% CF), High-CM (60% CM + 40% CF), Low-CM (30% CM + 70% CF), High-PM (60% PM + 40% CF), and Low-PM (30% PM + 70% CF). The results exhibited that the adding of organic manure significantly improved soil chemical traits such as soil organic C (SOC), total N (TN), and available N (AN). Similarly, applying the combined fertilizer led to significant increases in the leaf net photosynthetic rate (Pn), SPAD values, and rice grain nutritional and cooking characteristics according to Rapid Visco-Analyzer (RVA) profile. Average increases in SOC, TN, Pn, starch content (SC), and amylose content (AC) were 16%, 12%, 9%, 7%, 9%, and 12%, respectively, across the year in the Low-PM compared to the Pos-CF treatment. Moreover, the manure amendments significantly altered the RVA profile attributes, including peak viscosity, tough viscosity, final viscosity, and the setback and pasting temperatures compared to Pos-CF. Linear regression analysis revealed that SOC and TN were positively associated with leaf Pn and SPAD values. Further, leaf Pn and SPAD were positively correlated with rice grain SC and AC. The correlation heat map analyses revealed a positive correlation in the RVA profile between the soil properties and leaf physiological traits. These correlation analyses showed that the increase in soil chemical traits and leaf physiological activities played a significant role in higher rice grain nutritional and cooking quality. Overall, the findings of this study show that the integrated use of organic fertilizers and CF in rice fields enhances soil functionality and the quality of rice on a sustainable basis.

Resistant starch content and physicochemical properties of non-waxy rice starches modified by pullulanase, heat-moisture treatment, and citric acid

Physicochemical modification methods have been widely applied to increase resistant starch (RS) content of waxy starch, but their effects on the functional properties of non-waxy starches are not fully understood. In this study, five non-waxy rice starches with intermediate to very high apparent amylose contents (AAC) were modified by pullulanase (PUL), heat-moisture treatment (HMT) and citric acid (CA). RS contents, AAC, crystalline structures, pasting properties and thermal properties were analyzed. The three modification treatments were effective in increasing the RS contents, especially CA modification. PUL modified starches had relatively higher AAC and relative crystallinity (RC), and their crystalline patterns changed from A-type to mixed B + V type. Both HMT and CA increased gelatinization temperature significantly but had opposite effects on changing paste viscosity of different rice starches. Compared with other non-waxy rice varieties, high-amylose rice starch exhibited the highest RS, AAC, and RC after modification. This study provides practical information for improving the nutritional benefits of rice.

Preparation and physiochemical properties of enzymatically modified octenyl succinate starch.

The high viscosity and low solubility of octenyl succinate starch (OSAS) in water often lead to low reaction efficiency and uneven distribution of OSA groups, which can be solved by subjecting OSA starch to enzymatic digestion. Waxy corn starch is used to produce OSAS. The molecular weight of enzymolysis modified octenyl succinate starches (E-OSAS) decreased with the addition of enzyme, and the substitution of enzymatically digested OSAS was larger than that of OSAS. As the addition of pullulanase increased, the substitution of E-OSAS tended to increase and the apparent viscosity decreased significantly. The smaller its particle size and polydispersity index (PDI), the larger the absolute value of the zeta potential. E40 -OSAS with the smallest particle size and best homogeneity and stability had the smallest weight average molecular weight (1.38 × 106 g/mol), the smallest number average molecular weight (1.37 × 105 g/mol), and the largest degree of substitution of 0.019. The E-OSAS has not been investigated deeply enough, and the enzymatic treatment by pullulanase is not much studied, so this study is of great importance to provide some basis for the research of new microcapsules. PRACTICAL APPLICATION: This work aims to provide wall materials with lower viscosity and better encapsulation properties for the food industry. Waxy corns starch is used to manufacture OSAS. This wall material is a partly biodegradable material that is hydrophilic on the outside and hydrophobic on the inside, and its preparation process is in line with the concept of green chemistry.

Radio frequency energy regulates the multi-scale structure, digestive and physicochemical properties of rice starch

Radio frequency (RF) heating as an emerging technology was applied to regulate the structural, digestive and physicochemical properties of rice starch. In vitro digestibility results showed that RF treatment enhanced the resistant starch content and reduced the rapidly digestible starch content of rice starch, resulting in higher resistant to enzyme hydrolysis. Microstructure analysis indicated that RF treatment caused the granular surface erosions and morphology changes with increasing treatment time. RF treatment did not alter the A-type crystal form of starch, but disrupted the relative crystallinity, short-range molecular order, and lamellar structure in different degrees. Moreover, the DSC results suggested that starch orders with a higher thermal stability formed after RF treatment, thereby reducing the accessibility of starch granules to the enzyme. Furthermore, rapid viscosity analysis revealed that RF treatment significantly reduced the peak viscosity and breakdown of indica and japonica rice starch, while increased them in waxy rice starch. The rheological properties of rice starch were also changed after RF treatment. This work provides a theoretical basis for the application of RF technology in starch modification.

Effect of acid catalyst on pyroconversion of breadfruit ( Artocarpus altilis ) starch: Physicochemical and structural properties

This work produced pyrodextrins from breadfruit (Artocarpus altilis) starch and evaluated the effect of HCl and CH3COOH as catalysts of pyrodextrinization on physicochemical and structural properties of pyrodextrins. Pyroconversion was performed by spraying the acid solution on starch (1.82 g acid/kg starch) and heated to 140°C for 180 min. The pyrodextrins were analyzed for chemical composition, dextrose equivalent (DE), color parameters, solubility, intrinsic viscosity, infrared spectrum, and granule morphology. The pyroconversion decreased (p < .05) the ash content and the intrinsic viscosity of native starch. The HCl-pyrodextrin was slightly yellow, very water soluble with 8.8% DE. The CH3COOH-pyrodextrin was white, 8.8% soluble with 1.2% DE. The pyrodextrinization reduced α(1,4) bonds of glucans without drastically changing the granule’s morphology. The use of acetic acid was considered a milder treatment, however, it caused an increase in the total and soluble dietary fiber contents, supporting its use to produce pyrodextrins for food applications. Novelty impact statement This article provides the first report of pyrodextrinization of breadfruit (Artocarpus altilis) starch. The HCl as catalyst caused greater changes in starch properties than acetic acid. The acetic acid caused a 10% increase in the total and soluble dietary fiber contents of pyrodextrin.

Combined molecular and supramolecular structural insights into pasting behaviors of starches isolated from native and germinated waxy brown rice

In order to provide a theoretical basis on how germination treatment modulated the pasting behaviors of starches from native and germinated waxy brown rice, impacts of germination on the molecular and supramolecular structures and pasting behaviors were evaluated. Multiple analytical methods such as thermodynamics and spectroscopy were applied in this work for investigating the changes in starch multiscale structure and pasting behaviors. The results show that germination treatment contributed to an obvious increase in α- and β-amylase activities, which could degrade the starch chains and reduce the contents of double helices (50.9%–43.2%), short-range ordered degree (1.054–0.908), relative crystallinity (40.1%–30.5%), and lamellar ordering degree (dc, 6.09–5.46 nm) along with apparent erosion on starch granules. These structural amorphizations at the molecular and supramolecular levels could lead to the weakened entanglements and interactions among molecular chains, eventually reducing the characteristic viscosity (e.g., overall, peak, and final viscosity) of starch. This study may facilitate better development of germinated rice-based products.

Effects of connection mode on acid hydrolysis of corn starch during induced electric field treatment

This study aimed to explore the effect of induced electric field (IEF) treatment on acid hydrolysis of corn starch by altering the connection modes of sample coils of a 4-reactor IEF system. Results suggested that IEF treatment could enhance the hydrolysis of corn starch and series connection (1. RRRR, η=16ESi2Pin4ZSi+Zload) exhibited higher energy efficiency than parallel (9. (RRRR), η=4ESi2PinZSi+4Zload), thus contributing to more extensive hydrolysis. Although no new functional group was formed, the starch granules were partially cracked into pieces and the crystallinity was slightly increased after IEF-assisted hydrolysis. Differential scanning calorimetry results indicated that IEF-assisted hydrolysis increased the gelatinization temperatures but decreased the enthalpy of starch, with a greatest variation was observed by series connection. Rapid visco-analysis showed that IEF-assisted hydrolysis greatly decreased the pasting viscosity of corn starch and also series connection showed the strongest reduction. The obtained results could provide a theoretical guide for the applications of IEF technology in biomaterial processing.

Effect of heat-moisture treatment on the functional and rheological characteristics of cassava (Manihot esculenta) starch

The major drawback of most starchy food is its inability to withstand high-temperature conditions, shearing force and acidity, which limits its usage in the food industry. This study investigates the effect of heat-moisture treatment (HMT) at varying moisture content (10–30% wet basis), drying temperature (80–100 °C) and time (2–8 h) on the functional and rheological properties of cassava starch using response surface methodology (RSM) by adopting a Box–Behnken design method. Cassava roots were processed into modified starch under various processing conditions. Results showed an increase in the water absorption index, solubility and swelling power while there was a slight reduction in the loose bulk density and tapped bulk density. The starch viscosity ranged between 4182 and 4268 Cps. Consistency ranged between 2.51 and 2.56 g/mL and the flow behaviour index ranged between 2.70 and 2.82. Optimal processing conditions for cassava starch were achieved with a moisture content of 30%, drying temperature of 90 °C and time of 2 h. These variables are important to consider for processing of cassava starch with improved consumer acceptability and potential large-scale production of baked foods, gel formation and custard production.

Preparation of high solid content oxidized starch by acid pretreatment–H2O2 oxidation and its performance as the ligand in zirconium tanning

Highly-oxidized starch (HOS) is an excellent ligand for zirconium tanning in leather making. However, oxidation reaction can only be undertaken in diluted solution due to the high viscosity of starch, which leads to high oxidant consumption and low solid content of HOS, and therefore greatly limits its industrial application. Starch was predegraded by using HCl followed by H2O2 oxidation for preparing a practical oxidized starch (OST) ligand with high solid content. HCl (5%) remarkably reduced the viscosity of starch and simplified the subsequent oxidation, resulting in a decrease in H2O2 dosage from 60% to 40% and an increase in solid content from 10% to 38%. HCl broke the α-(1–4) glycosidic bond between glucose units, and H2O2 oxidation led to the generation of abundant carboxyl groups in OST. The OST with moderate molecular weight (Mw 5609 g/mol) and carboxyl content (6.48 mmol/g) made the tanning performance of OST–Zr comparable to those of HOS–Zr and chrome tanning agents. Therefore, this work gives new insights into the crop-polysaccharides based ligands application and exhibits huge potential for promoting industrial applications of zirconium tanning.