Steady and dynamic shear rheology of starches from different oat cultivars in relation to their physicochemical and structural properties

Effect of ultrasound geometry on the production efficiency of damaged starch: Determining rheology parameters, and non-isothermal reaction kinetics

Present study investigates the effects of probe size geometry on thermodynamic kinetics, rheology, and microstructure of wheat and tapioca starch. Ultrasound treatment using different probe diameters (20 mm and 100 mm) significantly influenced the gelatinization process. Results showed reduced enthalpy (ΔH) and Gibbs energy (ΔG), indicating enhanced gelatinization efficiency. According to the results, using a 20 mm and 100 mm probe leads to a reduction of 52.7 % and 68.6 % in reaction enthalpy for wheat starch compared to native starch, respectively. Microstructure analysis revealed structural changes, with ultrasound treatment leading to granular fractures and a sheet-like structure with air bubbles. The rheological behavior of the starches is found to exhibit shear thinning behavior, with the Casson model providing the best fit for the experimental data. Moreover, rheology modeling using Herschel-Bulkley and power law models showed increased viscosity and shear stress in larger probes. Numerical simulation data demonstrated that probe size influenced ultrasonic pressure, sound pressure level, and thermal power dissipation density, affecting fluid motion and velocity field components. Moreover, the maximum dissipated power decreases from 8.43 to 0.655 mW/m3 with an increase in probe diameter from 20 to 100 mm. The average yield shear stress values are calculated as 3.36 and 3.14 for wheat and tapioca starches, respectively. The larger probe diameter leads to greater entropy increases, with tapioca starch showing a 4.72 % increase and wheat starch a 4.97 % increase, compared to 2.56 % and 3.11 %, respectively, with the smaller probe. Additionally, the Keller-Miksis model provided insights into bubble dynamics, revealing increased pressure and temperature with higher pressure amplitudes.

Starch nanoparticles with predictable size prepared by alternate treatments of ball milling and ultrasonication

In this study, starch nanoparticles (SNPs) were prepared by alternate treatments of liquid nitrogen ball milling and ultrasonication. The impact, shear and friction forces produced by ball milling, and acoustic cavitation and shear effects generated by ultrasonication disrupted starch granules to prepare SNPs. The SNPs possessed narrow particle size distribution (46.91-210.52 nm) and low polydispersity index (0.28-0.45). Additionally, the SNPs exhibited the irregular fragments with good uniformity. The relative crystallinity decreased from 34.91 % (waxy corn starch, WCS) to 0-25.91 % (SNPs), and the absorbance ratios of R1047/1022 decreased from 0.81 (WCS) to 0.60-0.76 (SNPs). The SNPs had lower thermal stability than that of WCS, characterized by a decrease in Td (temperature at maximum weight loss) from 309.39 °C (WCS) to 300.39-305.75 °C (SNPs). Furthermore, the SNPs exhibited excellent swelling power (3.48-28.02 %) and solubility (0.34-0.97 g/g). Notably, oil absorption capacity of the SNPs (9.77-15.67 g/g) was rather greater than that of WCS (1.33 g/g). Furthermore, the SNPs possessed the lower storage modulus (G'), loss modulus (G″) and viscosity than that of WCS. The SNPs with predictable size and high dispersion capability prepared in this study lay a foundation for expanding the application of SNPs.

Effect of tertiary processing on physical, optical, phytochemical as well as rheological properties of high-protein rice

The first high-protein rice variety of India, CR Dhan 310, developed at ICAR-NRRI, Cuttack is being selected for the study. It contains 10.1% protein in milled rice as compared to 6-7% protein content in the milled rice of any other normal variety. It has intermediate amylose content (25.1%), medium bold grains rich in protein (10.1%) The significant changes in properties of raw and parboiled rice on processing were studied at statistical differences of p ≤ 0.05. These properties included physical, optical, antioxidant and rheological properties which changed with different processing techniques. All the three processes namely, puffing, popping and flaking increased the dimensions as compared to the raw rice. Peak viscosity measurements demonstrated the breakdown of starch molecules, with white rice having the greatest value (4145 cP) and popped rice having the lowest value (2017 cP) as a result of the starch granules being gelatinized during the production of popped rice. Highest anthocyanin content (2.93 mg/100 g) was observed in puffed rice, phenolic content (347.93 mg/100 g) was highest in popped rice and flaked/flattened rice showed highest flavonoid content (127.12 mg/100 g) indicating that tertiary processing of rice obtained higher values of phytochemicals when compared to the plain high-protein rice. This indicates that the processed products of rice can be consumed directly as ready-to-eat or can be used in preparation of other functional foods to combat malnutrition and build nutritional security. The study indicates that processing could improve the nutritional quality of the rice products.

Molecular morphology & interactions, functional properties, rheology and in vitro digestibility of ultrasonically modified pearl millet and sorghum starches

The present research investigated to study the effect of ultrasound treatment on isolated pearl millet starch (PMS) and sorghum starch (SS). Ultrasonication was applied to PMS and SS for 10, 15, and 20 min. Ultrasonically modified pearl millet and sorghum starches evaluated for their techno-functionality, pasting profile, morphology, in vitro starch digestibility, XRD, and molecular interactions. Ultrasound treatment increased water and oil absorption capacity, swelling power, and solubility with treatment time. For ultrasonicated PMS and SS, a significant increase (p < 0.05) in paste clarity (PC) (70.05 % and 67.23 %), freeze-thawing stability (FTS), gel consistency (GC) (25.05 mm and 32.95 mm), and in vitro starch digestibility were observed (57.70 g/100 g and 50.29 g/100 g), whereas no significant changes were recorded for the color values after the ultrasound treatment. Variations in pasting property were also observed in ultrasonicated starches with treatment duration. SEM images confirmed ultrasonication mainly forms pores and indentations on starch granule surface. FTIR spectra and X-ray diffractogram for ultrasonicated starches revealed a slight decrease in the peak intensity and A-type X-ray pattern with lower relative crystallinity (RC) than the native starches. G' > G″ value, indicating the elastic behavior and lower tan δ value, depicting viscous behavior and high gel strength.

The influence of cooperative fermentation on the structure, crystallinity, and rheological properties of buckwheat starch

The effects of co-fermentation of yeast and Lactiplantibacillus plantarum 104 on buckwheat starch physical properties were investigated by various analytical techniques. To investigate the regulations of starch modification during fermentation and to provide a foundation for improving the performance of modified properties of buckwheat starch food. The pasting properties were decreased by co-fermentation also resulted in a reduction in the relative crystallinity. Scanning electron microscopy (SEM) demonstrated that more holes and a relatively rough granule surface were seen in the co-fermentation group. Fourier transform-infrared spectroscopy (FT-IR) results suggested that co-fermentation fermentation decreased the degree of short-range order (DO) and degree of t1he double helix (DD). The results demonstrated that co-fermentation altered these properties more rapidly than spontaneous fermentation. In conclusion, Lactiplantibacillus plantarum 104 could be used for buckwheat fermentation to improve food quality.

Influence of chemical modifications on dynamic rheological behaviour, thermal techno-functionalities, morpho-structural characteristics and prebiotic activity of banana starches

Banana starch is explored for its use in food and pharmaceutical applications. In this study, in order to improve the techno-functional properties of native banana starch (NS), different chemical modifications namely acid thinning (AT), oxidation (OX), sodium-trimetaphosphate method (STMP), cross linking phosphorylation (CLP), hydroxypropylation (HYP) were employed. Among the modified starches, amylose content was higher in CLP starch and the least was observed in AT. Resistant starch (RS) of HYP (65.38 %) and CLP starches (62.76 %) were significantly higher than other modified starches. Lesser amylose, higher water solubility and lower swelling of AT starch resulted in inferior paste clarity and inability to make a firm gel. Non-Newtonian behaviour of starch gels were observed from static viscosity observations. The dynamic rheological behaviour of the starch gels affirmed the higher gel strength of STMP (0.46) and CLP (0.56) starches. Imperfection and exo-corrosion in starch morphology was observed through SEM and influence of chemicals on the starch structure was elucidated through FTIR and XRD analyses. Except AT starch, modified starches with higher RS resulted in lowering glycemic index (57-69 %). STMP starches recorded highest prebiotic activity score of 0.88. Chemical modifications enable to enhance the functionalities of banana starch and offers potential industrial uses.

Structure and physicochemical properties of cross-linked and acetylated tapioca starches affected by oil modification

This work investigated the structure and physicochemical properties of cross-linked tapioca starch (CTS), acetylated tapioca starch (ATS) and their counterparts (Oil-CTS and Oil-ATS). The results showed oil on the interface of starch granules promoted granule agglomeration after oil modification. Besides, oil modification could increase granule size and destroy the crystalline structure but did not affect the molecular structure of starch. Meanwhile, oil-modified starches did not form the V-type structure like amylose-fatty acid complex, suggesting that oil could not enter the helical cavity of amylose to form complex. Furthermore, compared with CTS and ATS, oil-modified starches had higher shear resistance, lower viscosity and gelatinization enthalpy. Notably, Oil-CTS possessed excellent emulsion stability, with the potential application as an emulsion stabilizer. This study revealed oil modification as an innovative method to endow starch with high shear resistance, low gelatinization enthalpy and excellent emulsion stability to meet the demands of food industries.

Current trends in the preparation, characterization and applications of oat starch - A review

Worldwide consumption of oats is gaining popularity due to its composition and multifunctional benefits of individual components. Oat starch being the major component accounts up to 60% of the dry weight of kernel, possess small granule size and high lipid content. Properties of starch substantially affect the quality of the product. Modification and characterization of starch is important for their specific applications that increase the utilization of oat starch. Different modification techniques greatly affect the functional, pasting, gelatinisation, textural, rheological, retrogradation properties and enzymatic digestibility of oat starches in comparison to native starch. Modified oat starch competes against other abundant and inexpensive cereal starches (rice and corn) that are available in modified forms in the market. This review summarises the current knowledge of physicochemical, morphological, pasting, functional, rheological and gelatinization properties, developments in the extraction and modification (physical, chemical and enzymatic) and applications of oat starch. Thus, this review will upgrade the scientific basis on oat starch being a unique source of starch for variety of applications.

Enhanced delivery of engineered Fe-Mn binary oxides in heterogeneous porous media for efficient arsenic stabilization

Heterogeneity in sediment and aquifer is universal, resulting in preferential flows of injected materials in the high permeability regions and forming flow by-passed zones in the low permeability regions during in-situ subsurface remediation. This adverse effect can considerably delay the completion of remedial operations and significantly increase the cost. Column experiments were designed and conducted to study the transport of starch- and starch-xanthan gum modified Fe-Mn binary oxide particles (SFM and SXFM) in saturated heterogeneous porous media and to reveal the particles' arsenic (As) stabilization performance. Fine-in-Coarse (FIC) and Coarse-in-Fine (CIF) patterns of heterogeneous packings were set up in the columns. Testing results demonstrated that starch-xanthan gum dual treatment on Fe-Mn binary oxides successfully improved the particles' migration capability in heterogeneous porous media and their distribution uniformity attributed to the profound shear thinning behavior of xanthan gum solution. The addition of xanthan gum to the system increased the viscosity and shear thinning property of the SXFM suspension, making it a better candidate for delivery. Both SFM and SXFM stabilized As in heterogeneously packed sediment collected from a contaminated site, with SXFM showing better stabilization performance than SFM. The stabilization effects of SXFM were 90.7-97.0%, compared to 82.0-95.2% of SFM.

Effect of dual modification sequence on physicochemical, pasting, rheological and digestibility properties of cassava starch modified by acetic acid and ultrasound

Dual modification of cassava starch was carried out using ultrasonication and acetylation by acetic acid by altering the sequence. The results revealed that the type of modification and sequence of modification for dual modified starches significantly affected the properties of starch. The swelling decreased for all the modified starches whereas solubility decreased for ultrasonicated starches but increased for acetylated starch and dual modified starch where acetylation was done after ultrasonication. The paste viscosities of all the modified starches were found to be significantly lower compared to native starch and the lowest viscosities were observed for dual modified starch where ultrasonication was done after acetylation. The resistant starch and slowly digestible starch content of the modified starches were significantly higher than in native starch, and the type of modification and sequence of modification for dual modified starches seemed to affect the digestibility of starches.

Rheological Analysis of the Structuralisation Kinetics of Starch Gels

Using the method of dynamic–mechanical analysis, the structuralisation kinetics of condensed starch solutions, cooled down to the temperature of 20 °C, was investigated. A close correlation of spatial crosslinking with local processes of macromolecule associations was discovered. It was found that depending on the concentration intervals of starch solutions, equilibrium nodes of the spatial network assume the form of either single or double hexagonal structures made up of bispiral chain associates. The increase of gel crosslinking, together with the passage of time, is the result of increasing the node functionality of the spatial network.

Isolation, modification, and characterization of rice starch with emphasis on functional properties and industrial application: a review

Starch is one of the organic compounds after cellulose found most abundantly in nature. Starch significantly varies in their different properties like physical, chemical, thermal, morphological and functional. Therefore, starch is modified to increase the beneficial characteristics and remove the shortcomings issues of native starches. The modification methods can change the extremely flexible polymer of starch with their modified physical and chemical properties. These altered structural attributes are of great technological values which have a wide industrial potential in food and non-food. Among them, the production of novel starches is mainly one that evolves with new value-added and functional properties is on high industrial demands. This paper provides an overview of the rice starch components and their effect on the technological and physicochemical properties of obtained starch. Besides, the tuned techno-functional properties of the modified starches through chemical modification means are highlighted.HighlightsNative and modified starches varies largely in physicochemical and functional traits.Modified physical and chemical properties of starch can change the extremely flexible polymer of starch.Techno-functional properties of the modified starches through chemical modification means are highlighted.Dual modification improves the starch functionality and increases the industrial applications.Production of novel starches is on high industrial demands because it mainly evolves with new value added and functional properties.

Oat starch: Physico-chemical, morphological, rheological characteristics and its applications - A review

Oat starch is getting attention owing to its usefulness and potential in a number of food and non-food applications. Starch is by far the main component of oat grains and possesses some unique chemical, physical, and structural properties when compared with other cereal starches. Oat starch offers untypical properties such as small size of granules, well-developed granule surface and high lipid content. Variation in amylose and amylopectin proportion along with the properties associated with the amylopectin molecule makes diversity in composition of oat starch. The pasting and rheological properties of oat starches control food product quality. This review articles outlines the recent developments in understanding of the starch isolation, chemical composition, morphology, pasting, rheological and thermal characteristics and various application of oat starch. Potential applications of oat starches are also reviewed.

Sensory, rheological and chemical characteristics during storage of set type full fat yoghurt fortified with barley β-glucan

β-Glucan, is a soluble dietary fiber and is obtained from number of sources including cereals. It possesses the nutraceutical characteristics and acts as functional bioactive ingredient in the fermented dairy product including yoghurt. In this concern, β-glucan isolated from barley having purity of (91.52%) was incorporated in different proportions (0.5, 1, 1.5 and 2%, w/v) during the full fat yoghurt preparation. The analysis of β-glucan carried out initially, indicated that the viscosity, water binding capacity, swelling power and solubility values were 92 Pa s, 3.17 g/g, 18.50 g/g and 3%, respectively, whereas, the total antioxidant activity obtained in terms of DPPH free radical scavenging activity was 27%. Based on these characteristics β-glucan extract had been considered as the choicest material for set type products like yoghurt. Thereafter, physiochemical, rheological and sensory characteristics of β-glucan incorporated yoghurt were evaluated during 1st, 7th and 14th days of refrigerated storage. Addition of β-glucan significantly (p ≤ 0.05) improved whey separation (syneresis), viscosity, texture profile and sensory characteristics during storage. The TPA characteristics such as hardness, cohesiveness and resilience of yoghurt samples improved significantly during storage with the incorporation of β-glucan whereas, β-glucan added yoghurt obtained higher consistency coefficient (K), thus, indicated a thicker and compact texture. Sensory analysis of stored yoghurt indicated that yoghurt samples in the present study containing even higher (1.5-2%) β-glucan level had obtained the higher average overall acceptability (8.1 to 8.3 on 9-point scale) score as compared to a low fat yoghurt containing lower β-glucan level (0.5%) reported in the literature.