Structure Of Starch Research Articles

Effect of Mild Alkali Treatment on the Structure and Physicochemical Properties of Normal and Waxy Rice Starches.

Mild alkali treatment can potentially be developed as a greener alternative to the traditional alkali treatment of starch, but the effect of mild alkali on starch is still understudied. Normal and waxy rice starches were subjected to mild alkali combined with hydrothermal treatment to investigate their changes in physicochemical properties. After mild alkali treatment, the protein content of normal and waxy rice starches decreased from 0.76% to 0.23% and from 0.89% to 0.23%, respectively. Mild alkali treatment decreased gelatinization temperature but increased the swelling power and solubility of both starches. Mild alkali treatment also increased the gelatinization enthalpy of waxy rice starch from 20.01 J/g to 25.04 J/g. Mild alkali treatment at room temperature increased the pasting viscosities of both normal and waxy rice starches, whereas at high temperature, it decreased pasting viscosities during hydrothermal treatment. Alkali treatment significantly changed the properties of normal and waxy rice starch by the ionization of hydroxyl groups and the removal of starch granule-associated proteins. Hydrothermal conditions promoted the effect of alkali. The combination of hydrothermal and alkali treatment led to greater changes in starch properties.

Optimisation of dry heat treatment conditions for modification of faba bean (Vicia faba L.) starch

Faba bean is a protein-rich starchy grain that is underutilised in the UK. The starch of faba bean can be modified using environmentally friendly methods like dry heat treatment (DHT) to enhance functional and its physicochemical properties. This study investigated the impact of dry heat temperature and time on the structure, functional and physicochemical properties of faba bean starch (FBS) using a two-factor central composite rotatable design. Factors (DHT temperature:100–150 °C and DHT time:0.5–5 h) with their respective α mid-point values led to 13 experimental runs. Selected pasting and functional properties were measured as response variables. Corn starch was included as a reference and compared with the FBS modified using the optimized conditions. DHT increased peak (approx. 2205–2267 cP), final (approx. 3525–3642 cP) and setback (approx. 1887–1993 cP) viscosities but decreased the amylose content of FBS. Colour, as measured by lightness value, morphology and crystalline type were not altered but the starches showed a loss of order and an increase in crystallinity after DHT. FBS appeared resilient to DHT but showed higher swelling power and pasting properties compared to the corn starch control. The optimum DHT conditions to produce starch with desirable properties are a temperature of 100 °C for 0.1716 h, with a desirability factor of 66 %.

Effect of Lycium barbarum L. polysaccharides on the quality of potato chips under low temperature frying and the mechanism of its action

Consumers increasingly desire healthier low-fat snack options. In this study, potato starch served as the substrate, and varying quantities of Lycium barbarum L. polysaccharide (0, 1, 3, and 5 g/100 g) were added to formula potato chips (FPC). The effect of LBPs on the sensory qualities, oil content, microstructure, and starch properties of FPC-LBPs was examined. The results showed that LBPs resulted in enhanced acceptability, reduced oil content, increased RS content, lower straight-chain starch leaching, and a gradual increase in the composite index (CI) of polysaccharides and starch in FPC-LBPs. The FPC-1LBPs exhibited the highest acceptability compared with the control samples. As the quantity of LBPs increased, the pores and cracks in the FPC-LBPs gradually decreased, and a polysaccharide wrapping layer formed on the surface of starch, which was the primary cause of the decrease in the oil content. With an increase in LBPs addition, the long-range and short-range ordered structure of starch progressively increased, and the hydrogen bonding interaction between LBPs and starch gradually strengthened, resulting in thinner FPC-LBPs. The enthalpy change of starch gradually decreased owing to LBPs, which delayed the pasting of starch and increased the RS content.

Effects of Controlled-Release Nitrogen Fertilizer at Different Release Stages on Rice Yield and Quality

The replacement of common urea with controlled-release nitrogen fertilizer can improve rice yield and quality, but the effect of controlled-release nitrogen fertilizer on rice yield and quality at different release stages is still unclear. In this experiment, two nitrogen application rates (240 kg/ha and 300 kg/ha) and five different nutrient release characteristics (urea and coated urea with controlled release periods of 30, 50, 70 and 90 days, respectively) were set up to explore the effects of nitrogen application rate, release characteristics and their interactions on rice yield, quality, starch structure, and physicochemical properties. The results showed that, compared with other controlled-release nitrogenous fertilizers, application of controlled-release nitrogenous fertilizers for 30 days and 90 days could increase rice yield (14.17% to 20.83%), and application of controlled-release nitrogenous fertilizers for 70 days and 90 days had the highest comprehensive evaluation of rice quality. The decrease of amylose content and the increase of protein content significantly improved the eating and nutritional quality of rice by changing the structure and physicochemical properties of starch particles. The results showed that in the comprehensive evaluation system based on rice yield and quality, under the condition of 300 kg/ha, controlled-release nitrogen treatment with a controlled release period of 90 days had the highest comprehensive score, which could increase rice yield and improve grain quality.

Differences in cooking taste and physicochemical properties between compound nutritional rice and common rice.

In this study, it was compared the physicochemical properties and cooking taste quality between four different types of compound nutritional rice (rice flour with the addition of other coarse grains, legumes, potatoes, and other powders, extruded as artificial rice grains) and common rice. We found that the protein and apparent amylose contents of compound nutritional rice were higher than that of common rice, up to 9.775% and 19.45% respectively. The γ-aminobutyric acid (GABA) and resistant starch contents were much lower than in common rice, and the dietary fiber content did not differ from that in common rice. The results of Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis revealed that the starch properties and structure of the compound nutritional rice changed due to high temperature and high pressure processing. In particular, the crystalline structures of starch became V-shaped. In addition, the results of artificial tasting and tasting meter showed that the taste of compound nutritional rice was generally inferior to that of common rice. In summary, compound nutritional rice had problems such as nutritional imbalance and poor taste. There was still a lot of room for improving the taste quality of compound nutritional rice. Therefore, the future development of compound nutritional rice should focus on both nutritional balance and taste improvement. The results of this paper also provided a certain theoretical basis for this.

Ultrasound and enzyme treatments on morphology, structures, and adsorption properties of cassava starch

Porous starch materials are environmentally friendly and renewable and exhibit high adsorption performances. Ultrasound and compound enzyme (α-amylase and glucoamylase) treatments were applied to prepare modified cassava starch. The granules, crystal morphology, crystal structure, and molecular structure of starch were investigated. The hydrolysis degree, solubility, swelling, and adsorption properties of cassava starch were analyzed. After the cassava starch was modified by ultrasound and enzyme treatments, the granule size of the starch decreased, and the surfaces were eroded to form pits, grooves and cavity structure. The starch spherulites weakened or even disappeared. The functional groups of starch did not change significantly, but the degree of crystal order decreased. The double-helix structure was reduced, and the crystal structure was composed of A + V-type crystals, with a decrease in crystallinity. The gelatinization temperature and thermal degradation temperatures enhanced. The enzymatic hydrolysis degree and solubility of the modified cassava starch increased. The swelling degree decreased, and oil adsorption, water adsorption improved. MB adsorption behavior of modified cassava starch closely followed a pseudo-second-order kinetics model and the Langmuir isotherm equation. These findings could help to understand the relationship between the structure and properties of modified starch, and guide its application in the field of adsorption.

Radio frequency regulates the multi‐scale structure and functional properties of starch from different genotypes of corn

SummaryThe purpose of this study was to investigate the multi‐scale structures, thermal, pasting, and textural properties of starch from different genotypes (dent and flint) of corn with varying moisture content (MC) (0.20, 0.25, and 0.30 kg kg−1 in dry basis) following radio frequency (RF) electromagnetic fields. As the MC increased, the amylose content in dent and flint corn starch rose from 14.60% to 19.70% and 14.80% to 24.63%, respectively, after the hot air (HA)‐RF treatment. With the increase in MC, the enhancement of starch–protein interaction and the change in starch molecule structure caused decreases in the crystallinity, short–range order structure, and enthalpy, while there were increases in the gelatinisation temperature, pasting viscosity, and textural properties of starch. The results showed that the RF treatment is an effective method for improving the processing performance of starch. Our data provide a foundation to expand the application of radio frequency in the food industry.

Effects of different pretreatment methods on the degree of substitution, structure, and physicochemical properties of synthesized malic acid sweet potato starch ester.

The preparation of malic acid starch ester (MSE) is mostly carried out using a high temperature method, but there are problems such as high energy consumption, long preparation time, and uneven heating. Microwave technology can be used to overcome these limitations. The semi-crystalline structure of starch granules hinders the modifier's access to the matrix, thus limiting the esterification reaction. Physical techniques can act on the interior of the starch to create a number of active sites, thereby facilitating the reaction of the starch with esterification reagents. Therefore, this study investigated the effect of starch pretreatment by microwave, heat-moisture, and ultrasonic techniques on the degree of substitution (DS), structure, and physicochemical properties of MSE synthesized by the microwave method. The DS of MSE was increased after pretreatments. The modified starch obtained by different pretreatment methods did not show new characteristic peaks, while the MSE synthesized showed new absorption peaks near 1735 cm-1. The granular structure and morphology of the modified starch obtained by microwave and heat-moisture pretreatment were gelatinized and aggregated, while some of the starch particles of the modified starch obtained by ultrasonic pretreatment appeared pore-sized. The relative crystallinity and gelatinization enthalpy of the MSE were reduced, but the crystallization pattern remained as A-type. Overall, the results suggest that various pretreatment methods can enhance the DS of MSE by disrupting the structure of starch. The findings of this study provide theoretical support for improving the DS of esterified starch. © 2024 Society of Chemical Industry.

Non-invasive exploration of malting barley (Hordeum vulgare) in vitro germination and varietal effects using short wave infrared spectral imaging and ANOVA simultaneous component analysis

ANOVA-simultaneous component analysis (ASCA) was applied to short-wave infrared spectral fingerprints of 5 malting barley varieties collected using a hyperspectral imaging system to determine the effect of germination, the influence of time and the influence of barley by means of a full factorial experimental design. ASCA indicated that there was a significant (p < 0.0001) effect of the germination status, the germination time and interaction on the spectral data for all varieties. The biochemical and physiological modification of the samples were characterised by visualisation of the longitudinal scores obtained from simultaneous component analysis for the germination time factor. This resulted in the visualisation and explanation of biochemical change over the course of barley germination as a factor of time. The relevant loadings indicated a significant change to the proteome, lipid and starch structure as driven by the uptake of water over time. The ASCA model were extrapolated to include the effect of barley variety to the already mentioned germination status and germination time factors, resulting once again in all the effects being significant (p < 0.0001). Here it was shown that all the barley varieties are significantly different from one another pre- and post-modification, based on the molecular vibrations observed in the short wave-infrared (SWIR) spectra, suggesting that the detection of biotic stress factors, such as pre-harvest germination, also differ for each variety, by indicating that the germination profile of each barley variety varies as a function of germination time. Thus, also the malting performance, germinative energy and chemical profile of each barley variety tested will vary before, during and after imbibition and germination – indicating the importance of malting commercial barley malt true to variety. These results indicate that (SWIR) spectral imaging instrumentation can possibly be used to monitor controlled germination of barley grain. Due to the shown ability of SWIR spectral imaging to detect small biochemical changes over time of barley grain during germination.

Ultrasonication: An Efficient Alternative for the Physical Modification of Starches, Flours and Grains.

Ultrasonic (USC) treatments have been applied to starches, flours and grains to modify their physicochemical properties and improve their industrial applicability. The extent of the modification caused by USC treatment depends on the treatment conditions and the natural characteristics of the treated matter. Cavitation leads to structural damage and fragmentation and partial depolymerization of starch components. The amorphous regions are more susceptible to being disrupted by ultrasonication, while the crystalline regions require extended USC exposure to be affected. The increased surface area in USC-treated samples has a higher interaction with water, resulting in modification of the swelling power, solubility, apparent viscosity, pasting properties and gel rheological and textural properties. Starch digestibility has been reported to be modified by ultrasonication to different extents depending on the power applied. The most important treatment variables leading to more pronounced modifications in USC treatments are the botanical origin of the treated matter, USC power, time, concentration and temperature. The interaction between these factors also has a significant impact on the damage caused by the treatment. The molecular rearrangement and destruction of starch structures occur simultaneously during the USC treatment and the final properties of the modified matrix will depend on the array of treatment parameters. This review summarizes the known effects of ultrasonic treatments in modifying starches, flours and grains.

Improvement in Storage Stability and Physicochemical Properties of Whole-Grain Highland Barley Pulp Prepared by a Novel Industry-Scale Microfluidizer System in Comparison with Colloid Milling.

The aim of this study was to assess the advantages of an industry-scale microfluidizer system (ISMS) to prepare whole-grain highland barley pulp (WHBP) compared with colloid milling. Storage stability was evaluated by particle size, gravity separation stability, and rheological properties, as well as the microstructure observation by scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLMS). The results showed that colloid milling failed to effectively homogenize the material, while ISMS sample surfaces were compact and smooth at higher pressures according to visual observation and SEM. The Turbiscan stability index of WHBP by ISMS was much lower as a result of colloid milling, demonstrating ISMS can improve WHBP stability. WHBP by colloid milling displayed a three-peak particle size distribution pattern, while a single-peak pattern was evident after ISMS treatment. A higher shear rate decreased the apparent viscosity, suggesting that WHBP was a shear-thinning fluid. According to CLMS, ISMS can successfully improve homogenization by disrupting the structures of oil bodies, proteins, and starches. The WHBP prepared by ISMS exhibited a higher β-glucan level than that prepared by colloid milling, and showed a significant increase in β-glucan level with ISMS pressure. These findings indicate that using ISMS to produce WHBP is viable for enhancing its storage stability and nutritional value.

Effect of ultrasound/CaCl2 co-treatment on the microstructure, gelatinization, and film-forming properties of high amylose corn starch

The effect of ultrasound/CaCl2 co-treatment on aggregation structure, thermal stability, rheological, and film properties of high amylose corn starch (HACS) was investigated. The scanning electron microscopy (SEM) images revealed the number of starch fragments and malformed starch granules increased after co-treatment. The differential scanning calorimetry (DSC) results showed the co-treated HACS got a lower gelatinization temperature (92.65 ± 0.495 °C) and enthalpy values (ΔH, 4.14 ± 0.192 J/g). The optical microscope images indicated that lesser Maltase crosses were observed in co-treated HACS. The results of X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) indicated ultrasound influenced the compactness of amorphous zone and CaCl2 damaged the crystalline region of HACS granules. Additionally, the rheology properties of HACS dispersion demonstrated the apparent viscosity of co-treated dispersion increased as the ultrasound time prolonged. The mechanical strength and structural compactness of HACS films were improved after ultrasound treatment. The mechanism of ultrasound/CaCl2 co-treatment improved the gelatinization and film-forming ability of HACS was that (i) ultrasound wave loosened the HACS granules shell, promoted the treatment of CaCl2 on HACS granules, and (ii) ultrasound wave improved the uniform distribution of HACS dispersion, increased the interaction between CaCl2 and starch chains during the process of film-forming.

Effect of wheat TaDOF6 overexpression on the molecular structure and physicochemical properties of grain starch and resistant starch

This study examined the effects of overexpressing the DOF (DNA binding with one finger protein) transcription factor gene, TaDOF6, on wheat grain native starch and Ⅲ-type resistant starch (RS3). Overexpression of TaDOF6 in the endosperm resulted in a significant increase in amylopectin content, particularly in long-branched chains, as well as larger starch particle size. Additionally, there was an increase in both rapidly and slowly digestible starches, along with an elevated level of native resistant starch. The enhanced crystallinity and orderliness of native starch, along with improved pasting properties, were also observed. However, TaDOF6 overexpression negatively impacted RS3 by reducing its crystal order, thermal stability, and pasting performance. Principal component analysis highlighted the substantial role of amylopectin in determining the crystal structure and physicochemical properties of starch. Moreover, a significant correlation was found between the particle size of RS3 and its physicochemical characteristics. Overall, these findings demonstrate that TaDOF6 overexpression alters the composition of grain starch, leading to improvements in its molecular structure and physicochemical properties.

Pullulanase-assisted bamboo leaf flavonoids optimize the instant properties, in vitro digestibility, and underlying mechanism in yam flour

In this study, pullulanase-assisted bamboo leaf flavonoids (BLF) were employed to ameliorate limitations of fluidity and digestibility of cooked yam flour via physicochemical properties, digestion, structure and interaction analysis. The results showed that 1) Pullulanase-assisted BLF significantly increased the water solubility (9.02% → 69.38%) and inhibited the swelling (5.54 g/g → 2.29 g/g) during heating and cooling of yam flour, causing it to have liquid-like rheological properties (the tanδ tended to 1). 2) Pullulanase and BLF synergistically affected the anti-digestion of yam flour, reducing the estimated glycemic index to a lower level (58.27 → 48.26, dose-dependent of BLF). 3) Pullulanase-assisted BLF mainly interacted hydrophobic with various components, especially starch, increasing the short/long-range ordered structure of starch, changing the secondary structure of proteins, and forming a tight three-dimensional network structure. This study provided a theoretical foundation for the development of functional foods using yam flour and its potential application in liquid foods.

Differences in structure, physicochemical properties, and in vitro digestibility of three types of starch complexed with tannic acid

The structure of starch often influences its interaction mode and affinity with polyphenols, subsequently impacting the functional properties of starch-polyphenol complexes. This study delved into the multiscale structure, physicochemical properties, and digestive performance of complexes formed by tannic acid (TA) with starches of different polymorphisms (corn starch (CS), potato starch (PS), and pea starch (ES)). The results revealed that TA induced notable changes in the surface morphology and aggregation behavior of starch pastes, with the most pronounced effects observed in ES. Elevated gelatinization enthalpy change and decreased thermal stability were observed in ES-TA complexes, contrary to complexes formed with CS and PS. TA enhanced the crystallinity of three pre-gelatinized starches, facilitating the formation of long-range ordered structures but disrupting short-range ordered structures, with effects more pronounced and TA-concentration-dependent in CS and ES rather than PS. The viscoelasticity of PS gel was strengthened, while that of CS and ES gels was reduced by TA. Digestive outcomes demonstrated that TA increased the resistance to digestion in all three starches, with CS exhibiting the most significant effect, followed by ES and PS. This might be linked to the binding modes of TA with different crystalline starches. The observed variations in regulatory effects on structure and function of starches from different sources combined with TA enhanced our understanding of TA-starch interactions, providing insights into the interaction between polyphenols and starch of different crystalline types.

Preserving potato perfection: Optimizing innovative drying techniques for maintaining physicochemical attributes and starch structure

To address the limitations of conventional hot air drying (HAD) for potato dehydration, pulsed vacuum drying (PVD) and humidity-controlled HAD (HC-HAD) were proposed as innovative techniques. In PVD, varying vacuum pulse durations (6, 8, 10, 12, and 14 min) and atmospheric pulse durations (2, 3, 4, and 5 min) were investigated. Under HC-HAD, different humidity control scenarios (40,30+30,90+CF, 50,30+30,90+CF, 40,30+CF, and 50,30+CF) were examined. The study revealed that a 14:2 duration pulsing in PVD retained the color and achieved the highest total phenol content (TPC) and antioxidation activity (conserving 97.50 % and 84.67 % of their fresh values, respectively) but had the longest drying time (260.00 min) compared to HC-HAD and HAD (139.45 min). The 50,30+CF strategy of HC-HAD exhibited the quickest drying time (116.79 min), maintained the color, TPC (87.97 % of the fresh value), and antioxidation activity (71.40 % of the fresh value), and achieved the best potato microstructure and starch structure. Furthermore, Artificial Neural Network simulations for HC-HAD conditions demonstrated significant reliability. These findings provide valuable insights for potato researchers and producers seeking to enhance preservation techniques and prolong the shelf life of potatoes as a staple crop.

Effects of heat‐moisture treatment on the multiscale structure and digestibility of sweet potato starch

SummaryThe effects of water content on the multi‐scale structure and digestibility of sweet potato starch (SPS) during heat‐moisture treatment (HMT) were studied, and the relationship between water content, starch structure and starch digestibility was analysed. The results showed that the surface of SPS granules changed after HMT, mainly in the form of depression, rupture and adhesion, and the change was more obvious with the increase of water content, and the crystalline structure changed from the original A‐type to A + V‐type. The relative crystallinity and double helix content decreased, the thickness of semi‐crystalline layered structure increased, and the peak intensity decreased. The molecular weight of SPS after HMT tended to be distributed in the low molecular weight range of 4 × 104 g mol−1 &lt; Mw &lt;4 × 105 g mol−1. These structural changes promoted the rearrangement of the intermolecular structure of SPS, which made amylase shield the original action site when acting on SPS, and converted part of rapidly digestible starch (RDS) content into slow digestible starch (SDS) and resistant starch (RS) content, resulting in the increase of SDS and RS content. Especially in HMT‐25, the RS content of SPS was the highest, which was 28.60%. The experimental data can provide theoretical support for broadening the application of SPS.

Analysis of starch content and multi-scale structure of reconstituted cut stems in tobacco

AbstractOn the basis of the relationship between the composition of the reconstituted cut stems and their functional positioning in the leaf formulation, this study improves the proportion of high-quality tobacco products by investigating the material basis of the effect of reconstituted cut stems on the quality of cigarette products, by characterizing the starch content, physicochemical properties, and characteristic structures of different components in tobacco products. The results showed that the starch content in reconstituted cut stems (4.93 ± 0.27%) was between high-quality tobacco leaves (4.48 ± 0.17%) and cut stems (5.13 ± 0.18%), indicating that the reduction of starch content during the processing of reconstituted cut stems is more conducive to the high-value treatment of reconstituted cut stems. At the same time, through the evaluation of the physico-chemical properties and multi-scale structural characteristics of starch particles, it was found that the starch of the reconstituted cut stems has a rock-like particle structure, and the short-range ordering on the surface increases, forming more ordered structural domains. In addition, the processed reconstituted cut stems increase the crystallinity of the starch. It also exhibits the typical B-type crystalline structure of starch, with stronger molecular chain interactions and high crystalline ordered arrangement. This study will provide technical guidance and theoretical support for improving the quality of reconstituted cut stems products, improving the bioavailability of tobacco products, reducing raw material costs, and effectively reducing the starch content of tobacco in the development of tobacco products.

Supramolecular structure and physiochemical properties of annealed maize starches: Effect of starch granule-associated surface and channel proteins

To investigate the effect of starch granule-associated surface and channel proteins (GSCP) on starch during annealing, normal maize starch (NMS) and waxy maize starch (WMS) were subjected to protease treatment then annealing for 0–36 h to study changes in structural and physicochemical properties. The removal of GSCP accelerated the rate of increase in granule size of NMS during annealing. XRD results showed that annealing initially decreases the crystalline order of starch granules, but with prolonged annealing, the relative crystallinity increases. Also, GSCP removal decreases the rate of reduction in relative crystallinity during annealing. The lamellar structure of starch becomes compact in the initial state of annealing. With extended annealing time, the rearrangement of the microcrystalline structure may result in a decrease in compactness. The dual treatment increased the thickness of crystalline lamellae (dc), and the removal of GSCP advanced the change of lamellar structure during annealing. From pasting results, the rigidity of swollen starch was reduced after GSCP removal, while it increased with annealing time for NMS. This study adopted a GSCP removal method that had minimal impact on the structure of starch granules, providing novel information about the role of GSCP in the annealing of maize starch.

Combined effects of nitrogen and sulfur fertilizers on chemical composition, structure and physicochemical properties of buckwheat starch

Buckwheat starch has attracted worldwide attention in the food industry as a valuable raw material or food additive. Nitrogen (N) and sulfur (S) are two nutrients essential to ensure grain quality. This study investigated the combined application of N fertilizer (0, 45 and 90 kg N ha−1) and S fertilizer (0 and 45 kg SO3 ha−1) on the chemical composition, structure and physicochemical properties of buckwheat starch. The results showed that increasing the fertilizer application decreased amylose content and starch granule size but increased light transmittance, water solubility and swelling power. The stability of the absorption peak positions and the decrease in short-range order degree suggested that fertilization influenced the molecular structure of buckwheat starch. In addition, increases in viscosity and gelatinization enthalpy as well as decreases in gelatinization temperatures and dynamic rheological properties indicated changes in the processing characteristics and product quality of buckwheat-based foods.