Starch Paste Research Articles

Impact of flaxseed gum on the aggregate structure, pasting properties, and rheological behavior of waxy rice starch

This study examines the effects of flaxseed gum (FG) on the aggregate structure, pasting and rheological properties of waxy rice starch (WRS). Results display an increase in the ordered molecular structure (R1047/1024), relative crystallinity (RC), compactness (α), and microphase heterogeneity (ε, density degree of nanoaggregates, from 3.52 to 4.23) for WRS-FG complexes. These suggested FG facilitated the development of more organized molecular and crystalline structures of WRS, accompanied by the formation of ordered nanoaggregates with higher density (i.e., nano-aggregation structure). Also, FG addition resulted in the formation of enhanced gel network structure characterized by thicker layer walls and more uniform pores. These structural transformations contributed to a rise in gelatinization temperature (To, from 56.90 °C to 62.10 °C) and enthalpy (ΔH), as well as alterations in paste viscosities (PV, from 1285.00 mPa·s to 1734.00 mPa·s), and the rigidity of network structure (e.g., decreased loss tangent). These results indicate that FG could effectively regulate the techno-functional properties of WRS by rationally controlling the starch intrinsic structures of starch. And this study may improve the pasting and gelling properties of starch, thus driving the development of high-quality starchy foods and prolonging their shelf life, especially for glutinous rice flour products.

The effect of concentration on rheological properties of sago (Metroxylon sagu) starch

The concentration of starch is one of the main factors influencing the rheological characteristics of starch-based foods. The rheological behavior of sago starch at varied concentrations of 3, 5, 10, 20 and 30% (w/w) were investigated using small oscillatory temperature and frequency sweep measurements. All concentrations of sago starch expressed less solid-like behavior, with tan δ values of approximately 0.2. A flowable viscous paste of sago starch was generated at low concentrations (3 and 5% (w/w)). The gel network formation of sago starch initially occurred at a critical concentration of 10% (w/w). Further increases in the concentration to 20 and 30% (w/w), stronger gel network formation was occurred. In addition, the tan δ values for concentrations of 20 and 30% (w/ w) were approximately 0.2 with elastic and soft gel characteristics. A positive power law correlation between G' and sago starch concentration was found, with a coefficient of determination (R2 ) value of 0.99. The gelatinized sago starch was unstable as a frequency sweep was applied, indicating that it may be less stable during storage or processing.

Enhancing starch functionality through synergistic modification via sequential treatments with cold plasma and electron beam irradiation

The impact of dual sequential modifications using radio-frequency (RF) plasma and electron beam irradiation (EBI) on starch properties was investigated and compared with single treatments within an irradiation dose range of 5–20 kGy. Regardless of sequence, dual treatments synergistically affected starch properties, increasing acidity, solubility, and paste clarity, while decreasing rheological features with increasing irradiation dose. The molecular weight distribution was also synergistically influenced. Amylopectin distribution broadened particularly below 10 kGy. Amylose narrowed its distribution across all irradiation doses. This was due to dominating EBI-induced degradation and molecular rearrangements from RF plasma. With the highest average radiation-chemical yield (G) and degradation rate constant (k) of (2.12 ± 0.14) × 10−6 mol·J−1 and (3.43 ± 0.23) × 10−4 kGy−1, respectively, upon RF plasma pre-treatment, amylose underwent random chain scission. In comparison to single treatments, dual modification caused minor alterations in spectral characteristics and crystal short-range order structure, along with increased granule aggregation and surface irregularities. The synergistic effect was dose-dependent, significant up to 10 kGy, irrespective of treatment sequence. The highest synergistic ratio was observed when RF plasma preceded irradiation, demonstrating the superior efficiency of plasma pre-treatment in combination with EBI. This synergy has the potential to lower costs and extend starch's technological uses by enhancing radiation sensitivity and reducing the irradiation dose.

Preparation of a Novel Adhesive from Highly Fibrillated Kozo Fibre for Paper Conservation

Abstract In this study, Kozo fibres were fibrillated using the stone wet milling method and the wet atomisation method both deriving from nanocellulose production processes. Kozo fibres with a high degree of external fibrillation were obtained by using the stone mill wet grinding method. Although fibres exhibited the same structure as untreated Kozo fibres, their bonding properties improved. Applying the wet atomisation method, fibrillated Kozo fibres with different degrees of fibrillation were obtained depending on the number of treatments. Fibrillated Kozo fibres can be used in conservation as an adhesive for lining and other stabilisation treatments and may in certain cases replace starch paste, which is susceptible to microbiological damage. Only Kozo fibres and water were used in both mechanical fibrillation methods; therefore, the resulting material can be considered a safe alternative to more traditional adhesives.

Viscosity of Wheat Starch Paste Used in Traditional Chinese Conservation Techniques

Abstract In traditional Chinese conservation of historic books and mounted scrolls, the preparation and use of paste is an important process step. The viscosity of the paste is a key factor to consider, taking into account various parameters such as conservation technique, paper condition, or paper thickness. This study aims to determine the viscosity variation of diluted and thick pastes used in traditional Chinese conservation techniques with a rotary viscometer. During conservation treatment, as the number of restored leaves increases, the viscosity of diluted paste tends to increase significantly. The study highlights the different requirements for viscosity depending on its use either in Chinese books or Chinese hanging scrolls and emphasizes the importance of monitoring and adjusting paste viscosity during the conservation process. The use of a rotary viscometer, along with the traditional finger test method, is a significant step forward in improving the accuracy and efficiency of determining paste viscosity.

The Effects of Tremella fuciformis Polysaccharide on the Physicochemical, Multiscale Structure and Digestive Properties of Cyperus esculentus Starch.

In this study, we have investigated the effects of Tremella fuciformis polysaccharide (TP) on the pasting, rheological, structural and in vitro digestive properties of Cyperus esculentus starch (CS). The results showed that the addition of TP significantly changed the pasting characteristics of CS, increased the pasting temperature and pasting viscosity, inhibited pasting, reduced the exudation of straight-chain starch and was positively correlated with the amount of TP added. The addition of the appropriate amount of TP could increase its apparent viscosity and enhance its viscoelasticity. The composite system of CS/TP exhibited higher short-range ordered structure and solid dense structure, which protected the crystal structure of CS, but was related to the amount of TP added. In addition, the introduction of TP not only decreased the in vitro digestion rate of CS and increased the content of slow-digestible starch (SDS) and resistant starch (RS), but also reduced the degree of digestion. Correlation studies established that TP could improve the viscoelasticity, relative crystallinity and short-range order of the CS/TP composite gel, maintain the integrity of the starch granule and crystalline structure, reduce the degree of starch pasting and strengthen the gel network structure of CS, which could help to lower the digestibility of CS.

A comparative study on the gel and structural characteristics of starch from three rice varieties when combined with Mesona chinensis polysaccharides

Mesona chinensis polysaccharide (MCP) has excellent gel-forming characteristic, previous studies showed that MCP could affect the gelling and structural properties of rice starch, but the effect of MCP on rice starch from different types is not clarified. In this study, the effects of MCP on the pasting, rheological, and structural characteristics of glutinous rice starch (GRS), japonica rice starch (JRS), and indica rice starch (IRS) were investigated. The results showed that GRS-MCP has the best viscosity, its peak and final viscosities are higher than JRS-MCP and IRS-MCP. The gel network structure was enhanced by MCP in the order of IRS > JRS > GRS, which was reflected by greater elasticity, higher gel strength and hardness, and less free water in JRS-MCP and IRS-MCP. MCP also enhanced the ordered structure and thermal stability of the three starch gels, which is conducive to their application in the market. These findings provide new theoretical insights to produce rice starch-based foods.

Effect of atmospheric pressure plasma jet on the structure and physicochemical properties of wheat starch.

The effect of atmospheric pressure plasma jet (APPJ) with different discharge power (0, 400, 600, and 800 W) on the structure and physicochemical properties of wheat starch were evaluated in this study. After APPJ treatments, significant declines in peak viscosity, breakdown viscosity, and final viscosity of wheat starch pasting parameters were observed with increase of plasma treatment power. Being treated with discharge power of 800 W, the PV and BD value of wheat starch paste significantly dropped to 2,578 and 331 cP, respectively. Apparently, APPJ could raise the solubility of wheat starch, while reduce the swelling capacity, and also lower the G' and G″ value of wheat starch gel. Roughness and apparent scratch was observed on the surface of the treated wheat starch granules. Although APPJ treatment did not alter wheat starch's crystallization type, it abated the relative crystallinity. APPJ treatment might be useful in producing modified wheat starch with lower viscosity and higher solubility.

Changes in rheology and components during the processing of Chinese traditional handmade hollow dried noodle

The study of the changes in rheological properties and components during the processing of Chinese traditional handmade hollow dried noodle (HHDN) is essential to explaining the excellent quality of HHDN. The dynamic oscillation frequency sweep, stress relaxation, and uniaxial extension characteristics of the dough after kneading, stretching, and resting were investigated at six sampling points during the processing of HHDN. The result showed that stretching led to an increase in G' and G0, and a significant decrease (P < 0.05) in extensibility from 131.02 mm to 57.99 mm. Confocal laser scanning microscopy (CLSM) was used to observe the microstructure of the gluten network, which was destroyed during stretching and restored during resting. Studies of changes in components showed that the stretching process resulted in a decrease in GMP content from 3.24 (g/100 g) to 3.18 (g/100 g), and the resting process resulted in β-sheets decreasing significantly (P < 0.05). The degree of starch pasting increased significantly (P < 0.05) after stretching. The results of the correlation analysis showed that components changes were highly correlated with the rheological properties during the processing of HHDN.

Green banana (Musa ssp.) mixed pulp and peel flour: A new ingredient with interesting bioactive, nutritional, and technological properties for food applications

This study aimed to characterize and evaluate the in vitro bioactive properties of green banana pulp (GBPF), peel (GBPeF), and mixed pulp/peel flours M1 (90/10) and M2 (80/20). Lipid concentration was higher in GBPeF (7.53%), as were the levels of free and bound phenolics (577 and 653.1 mg GAE/100 g, respectively), whereas the resistant starch content was higher in GBPF (44.11%). Incorporating up to 20% GBPeF into the mixed flour had a minor effect on the starch pasting properties of GBPF. GBPeF featured rutin and trans-ferulic acid as the predominant free and bound phenolic compounds, respectively. GBPF presented different major free phenolics, though it had similar bound phenolics to GBPeF. Both M1 and M2 demonstrated a reduction in intracellular reactive oxygen species (ROS) generation. Consequently, this study validates the potential of green banana mixed flour, containing up to 20% GBPeF, for developing healthy foods and reducing post-harvest losses.

Effect of ultrasound-assisted enzyme pretreatment on γ-aminobutyric acid content, eating quality and starch properties of germinated brown rice

A novel technique has been developed to increase γ-aminobutyric acid levels and enhance the quality of germinated brown rice (GBR) by ultrasound and enzyme treatment. The combined use of ultrasonic and enzyme treatments notably enhanced the germination rate of brown rice. Additionally, the γ-aminobutyric acid content substantially improved from 18.79 ± 1.87 mg/100 g to 38.60 ± 3.19 mg/100 g when compared to the untreated group. Moreover, the cracks produced on the GBR surface and disruption of the starch structure resulted in increased water absorption, shortening of cooking time, and reduction in GBR hardness, thereby improving the cooking and edible quality of GBR. Additionally, ultrasonic and enzyme treatments increased the amount of fast-digestible starch and enhanced starch digestibility. However, they had minimal impact on the crystal structure, degree of crystallinity, and heat energy changes during the starch pasting process of GBR.

Physicochemical, Quality and Flavor Characteristics of Starch Noodles with Auricularia cornea var. Li. Powder.

Auricularia cornea var. Li., as an edible mushroom rich in various nutrients, could be widely used in noodle food. This study aimed to investigate the effect of Auricularia cornea var. Li. (AU) powder on the gel properties, structure and quality of starch noodles. Taking the sample without adding AU powder as a control, the addition of AU powder enhanced the peak viscosity, trough viscosity, final viscosity, breakdown, setback, peak time, gelatinization temperature, G' (storage modulus) and G'' (loss modulus). Meanwhile, the incorporation of AU powder significantly enhanced the stability of the starch gel structure and contributed to a more ordered microstructure also promoting the short-term aging of starch paste. In vitro digestion results displayed lower rapid digestibility (21.68%) but higher resistant starch content (26.58%) with the addition of AU powder and increased breaking rate, cooking loss, swelling index and a* and b* values. However, it decreased dry matter content and L*, particularly the reducing sugar content significantly increased to 4.01% (p < 0.05), and the total amino acid content rose to 349.91 mg/g. The GC-IMS library identified 51 VOCs, and the OPLS-DA model classified 18 VOCs (VIP > 1). Overall, the findings indicate that starch noodles with the addition of AU powder may provide greater nutritional quality, gel stability and starch antidigestibility.

Characterization of Starch Properties in Diverse Pea Accessions: Structural, Morphological, Thermal, Pasting, and Retrogradation Analysis

AbstractThe present work evaluates starch from 29 diverse pea accessions for structural (amylose content and amylopectin chain length distribution), granule size distribution, thermal, pasting, and retrogradation properties. Amylose content and the proportion of amylopectin chains with the degree of polymerization (DP) of 6–10, 11–20, and &gt;20 vary in the range from 21.4% to 57.0%, 17.9% to 25.8%, 64.0% to 66.5%, and 9.4% to 16.7%, respectively. Starches with a higher proportion of small granules (&lt;5 µm) have a greater proportion of amylopectin chains with DP &gt; 10 and exhibit higher transition temperatures/enthalpy and vice versa. Retrogradation in starch pastes relates negatively to the proportion of amylopectin chains with DP &lt; 10. Paste viscosities relate negatively with amylopectin chains with DP &gt; 10, amylose content, and retrogradation while positively with transition temperatures/enthalpy and the potential of granules to swell.

The Effects of D‐Allulose on the Gelatinization and Recrystallization Properties of Starches from Different Botanical Sources

AbstractD‐allulose (Alu), a rare sugar, has proven to be a low‐caloric sugar with potential health benefits. Previous studies have reported that compared with sucrose (Suc), Alu suppresses an increase in gelatinization temperature and retards retrogradation in glutinous rice starch. This study investigates the effect of Alu on gelatinization, water activity, and recrystallization behavior of various starch sources (potato, wheat, tapioca, corn, normal rice, and glutinous rice). MicroDSC results show that compared with D‐glucose (Glc), D‐fructose (Fru), and Suc, Alu does not significantly increase the gelatinization temperatures of the starch suspensions. Alu decreases water activity in the same degree as Fru in wheat, tapioca, corn, normal rice, and glutinous rice starch gels but not potato starch gels. Alu has a stronger suppression effect on recrystallization of normal and glutinous rice compared to potato, wheat, and tapioca after 14‐day storage of 2% starch pastes at 4 °C. These findings suggest that Alu can be a better plasticizer than Suc, Glc, and Fru in most starch sources but retards recrystallization of only normal and glutinous rice starches.

Structural, Thermal, Pasting and Digestion Properties of Starches from Developing Root Tubers of Sweet Potato.

Three sweet potato varieties with white-, yellow- and purple-fleshed root tubers were harvested at 100, 120, 140 and 160 days after planting (DAP). Their starch structural, thermal, pasting and digestion properties were measured to reveal the influences of harvesting dates on the physicochemical properties of sweet potato root tuber starch. Though starches from different varieties displayed some differences in physicochemical properties due to their different genetic backgrounds, they were influenced by harvesting date in similar ways. Starches isolated from root tubers at 100 and 160 DAP exhibited lower granule sizes than those at 120 and 140 DAP. The amylose content was higher in root tubers at 100 and 120 DAP than at 140 and 160 DAP. Starches from root tubers at 100 DAP exhibited CA-type X-ray diffraction patterns, and then the B-type crystallinity gradually increased at later harvesting dates. The different harvesting dates had no significant effects on the short-ranged ordered structure and lamellar thickness of starch, but the lamellar peak intensity decreased significantly at later harvesting dates. Starch had a lower gelatinization temperature and a wider gelatinization temperature range in root tubers at 140 and 160 DAP than at 100 and 120 DAP. The higher peak viscosity and lower pasting temperature were associated with the late harvesting date. The digestion of starch had slight differences among root tubers at different harvesting dates. The harvesting dates of root tubers played more important roles in starch properties than the variety. This study would be helpful for breeders, farmers and sweet potato starch users.

Assessment of the Baking Properties of Rye Flour Based on the Polysaccharide Content and Properties

This study aimed to determine the baking quality of rye flour in terms of the content and properties of its polysaccharides, i.e., starch and pentosans. The study materials were low- and high-extract rye flours produced in industrial mills from the rye grain of two growing seasons (2019 and 2020). The results of the starch content, falling number, amylograph properties, DSC test, content of pentosans, swelling curve test, and laboratory baking test were determined. It was found that the type of flour had a greater impact on the baking quality of rye flour than the year of its production. Research has shown that the most frequently used parameters, such as the falling number and the maximum viscosity of starch paste, are not good indicators for assessing the baking value of currently produced rye flours. From the parameters used for evaluating the properties of the starch–amylolytic complex, the initial and onset temperatures for starch gelatinization were the best indicators for evaluating the baking quality of rye flour. This study revealed a significant correlation between the pentosan content (total, water soluble, and insoluble), swelling curve parameters and quality parameters of rye bread, such as the specific bread volume, bread crumb moisture, and bread crumb hardness. Assessment of the baking value of rye flour based only on the evaluated properties of the starch–amylolytic complex is currently not sufficient to determine the baking quality of rye flour and predict the quality of rye bread. This study on the baking quality of rye flour should be extended to include the assessment of the dough properties related to the pentosan content and the enzymes that degrade these components. It was shown that the properties of rye dough related to the content of pentosan can be characterized based on the swelling curve test as a method that, together with the initial and onset starch gelatinization temperatures, allows better assessment of the baking quality of the commercial rye flour and its suitability for the good-quality rye bread production.

Changes in the pasting and rheological properties of wheat, corn, water caltrop and lotus rhizome starches by the addition of Annona montana mucilage

Annona montana mucilage (AMM) is a novel mucilage with unique but limited information. This study investigated the effects of AMM addition on the pasting and rheological properties of wheat starch (WS), corn starch (CS), water caltrop starch (WCS), and lotus rhizome starch (LRS). The addition of AMM generally increased the pasting temperature and peak viscosity, but reduced the setback value of all starches to varying degrees, and the initiation of viscosity-increase for cereal starch/AMM systems during pasting occurred at lower temperatures, accompanied with a distinctive two-stage swelling process as well as lower peak and final hot paste viscosity at 50 °C. AMM significantly increased the pseudoplasticity and entanglement of the systems to varying degrees (LRS > WS > WCS > CS). Under a constant shear rate of 50 s−1, the consistency level was found to fall in honey-like for cereal starch/AMM groups, and honey-like to extremely thick levels for WCS and LRS/AMM groups. Except for the WCS/AMM systems, the storage and loss modulus as well as tanδ increased with increasing AMM concentration. Short-term retrogradation of starch at 4 °C was pronouncedly retarded by the addition of AMM for WS, CS and WCS groups, but was less affected for LRS group.

Effect of Soy Protein Isolate on Pasting, Rheological, and Textural Attributes of Potato Starch

AbstractThe effects of different concentrations of soy protein isolate (SPI) on the functional, rheological, pasting, and structural properties of potato starch (PS) are investigated. The water and oil absorption capacity (OAC) of PS‐SPI mix increased significantly with the addition of SPI. Gel strength, peak, final, breakdown, and setback viscosity of PS decreases, whereas the pasting temperature increases with an increase in SPI fraction. Both the Herschel–Bulkley and power law model are found to equally fit in steady state rheology. The PS‐SPI blend exhibits pseudoplastic behavior. The addition of SPI decreases the storage (G′) and loss modulus (G″). SPI also lowers the flow stress values in the amplitude sweep test. Frequency sweep confirms the formation of weak gel formation in PS‐SPI blend by exhibiting a lower value of G′ and G″ than the pure starch. The microstructure of composite gel appears less dense with greater pore size than starch gel. The hardness of the SPI‐PS blend gel decreases from 6.76 to 0.85 N when the SPI content is increased from 0% to 50%. Fourier transform infrared (FTIR) confirms that no chemical groups are formed or destroyed during the composite gel‐making process.

FACILITATING THE APPLICATION OF STARCH PASTE IN THE CONSERVATION OF PAPER ARTWORKS

Starch paste is an adhesive that is used in the field of book and paper conservation. This adhesive has a very short shelf life, and for this reason, it must be prepared in small quantities. Also, preparing starch paste for use in protection is a time-consuming process. This research was done with the aim of facilitating the use of starch paste in the conservation of paper works, long-term storage of starch pastes without fungicidal additives and increasing its durability in the long term without changing the quality of the adhesive. The application of fresh starch pastes and activated starch film increased the pH of the samples coated by these adhesives compared to the control samples without adhesive. The samples covered by the activated starch film after moist-heat aging and light aging had the highest pH compared to other samples. The samples coated with fresh starch paste showed the lowest amount of color changes (∆E*) after moist-heat aging and light aging, respectively. Application of fresh starch paste and activated starch film increased the tensile strength of the samples. After aging, the tensile strength of the samples decreased compared to the previous stage, but the tensile strength of the samples covered by these adhesives increased compared to the control samples without adhesives. The adhesion of the samples decreased after aging. The samples coated with fresh starch paste had the highest adhesion after light aging. Also, after moist-heat aging, the samples covered by the activated starch film had the highest amount of adhesion.

Impacts of Konjac Glucomannan on the Pasting, Texture, and Rheological Properties of Potato Starch with Different Heat–Moisture Treatments

AbstractFew studies reported the impact of hydrocolloid addition on starches after heat moisture treatment (HMT). In this study, potato starch is modified by HMT under different moisture content (18–35%), and the impact of konjac glucomannan (KGM) addition on the pasting, gel texture, and rheological properties of potato starch after HMT are investigated. The results showed that after HMT, the granule structure of the starch is changed with higher heat stability, shown as higher pasting temperature and trough viscosity. The impact of KGM addition is similar on the potato starch before and after HMT, but the change extent of the latter is larger in most cases, such as decreased pasting temperature and gel hardness, increased peak viscosity, breakdown viscosity, and final viscosity. This indicated that KGM benefited the gelatinization behavior of HMT starch but might not enhance the retrogradation process. The intrinsic high viscosity of KGM in water resulted in a softer starch gel and also contributed to the enhanced shear stress of the mixture paste. Therefore, the impact of KGM on the HMT starch is more significant than the original starch, and this guided the use of HMT starch in the food industry with other hydrocolloid involvement.