Native Corn Starch Research Articles

Effect of starch categories and mass ratio of TA/starch on the emulsifying performance and stability of emulsions stabilized by tannic acid-starch complexes

This study compounded natural corn starch (CS), mung bean starch (MBS) and potato starch (PS) with tannic acid (TA) to stabilize O/W Pickering emulsion. The effect of TA/starch mass ratio (0–0.25) and three starch categories on particle properties, emulsifying properties, lipid oxidation, freeze-thaw stability, emulsion powder and digestive properties were comprehensibly investigated. In detail, the TA/starch complexes size increased gradually (91.14 nm–200.87 nm) and the hydrophobicity first increased and then decreased (TA/CS > TA/MBS > TA/PS) with increasing TA/starch mass ratio. In addition, the emulsifying ability of TA/starch complexes also increased first and then decreased with increasing mass ratio, especially TA/CS system was the best, which was the same as the hydrophobicity conclusion (θow = 80.46°). Moreover, four starch-based emulsion application characteristics were further evaluated to reveal interface structure. Compared to CS and PS system, TA/MBS emulsion had stronger ability to resist the oil oxidation (TBA = 2.54 μg/mL), destruction of ice crystal (whiter emulsion powder) and digestive enzymes (FFAs = 75.33 %). It mainly attributed to the crosslinking network structure and the highest surface load of TA/MBS complexes. This study would provide new ideas for the design and application of emulsifying properties and emulsion stability.

Improvement of pasting behavior and retrogradation inhibition of normal corn starch treated with phytic acid and malic acid

Phytic acid (PA) and malic acid (MA), as environmentally friendly, plant-based water-soluble acids, were applied to normal corn starch during dry heating at mildly acidic pH to improve its gelatinization and retrogradation behaviors. A significant increase in peak viscosity (5011–6338 mPa·s) was observed in starch treated with MA compared to native corn starch (1162 mPa·s). The treatment with PA and MA further increased the peak viscosity (8140–8621 mPa·s). The interactions of PA and MA with starch were analyzed using ICP-OES, FTIR, and 13C CP/MAS NMR. Swelling power and solubility increased in MA and PA + MA starches. After storage at 4 °C for 14 d, MA and PA + MA starches produced transparent and fluid gels without forming B-type crystals, which indicated inhibition of starch retrogradation by PA and MA treatments. In conclusion, dry heating with PA and MA produced starch with remarkably superior paste viscosity, swelling, and inhibition of retrogradation.

Solvent-free synthesis of starch citrate via dry heat reaction: An in-depth analysis on structural and physicochemical properties

The main objective of this study was to determine the feasibility and validity of the solvent-free dry heat reaction by investigating the structural and physicochemical properties of the starch citrates. Initially, a solid blend of native corn starch (NCS) and citric acid (CA) was heated in a preheated oven followed by further heating under continuous stirring to facilitate the reaction. The presence of ester bonds in the starch citrates was confirmed using Fourier Transform Infrared Spectroscopy (FTIR), which revealed a new absorption peak at 1738 cm−1. The starch citrates (SC) showed an increased thermally stable resistant starch (RS) content, with a thermally stable RS content of 74.37% and enhanced solubility. The solid-phase prepared starch citrates demonstrated reduced relative crystallinity, decreased swelling power, and lower pasting viscosities than native corn starch. Overall, these findings suggest that the solvent-free method of dry heat reaction between corn starch and citric acid is a viable technique for green preparing starch citrates.

Fractionation of debranched starch with different degree of polymerization and its effect of epigallocatechin gallate

Herein, five distinct degrees of polymerization (DP n‾) of debranched starch (DBS) were separated from native corn starch based on their differential solubility in aqueous/ethanol solutions of different volumetric ratios (1:1.5 and 1:3). Compared with the DBSP (DP n‾ 24.53 and DP n‾ 19.36), DBSs (DP n‾ 8.85 and DP n‾ 7.32) were found to have an amorphous crystal structure, resulting in lower thermal stability and an inability to form a complex with iodine. Furthermore, the proportion of rapidly digestible starch (RDS) in DBSP decreased, while the proportions of slow-digestible starch (SDS) and resistant starch (RS) increased. Additionally, the starch microparticles (SMPs) self-assembled from DBSp exhibit a larger particle size and a more regular shape than those formed by DBSs. Moreover, DBS-based SMPs (DBS-SMPs) with the maximum encapsulation efficiency and loading capacity of epigallocatechin gallate (EGCG) in DBSP3.0 (20) reached 88.67% and 22.35%, respectively. The EGCG loaded in EGCG@DBS-SMPs exhibited excellent radical scavenging activity.

Structure and Digestibility of Spray‐Dried Corn Starch: Influence of Post‐Treatments

AbstractResistant starch (RS) has being attracted attention due to its health benefits. In this study, combination of spray drying and post‐treatments is adopted to prepare post‐treated spray‐dried corn starch (PSDCS) with high content of RS. Effect of post‐treatment conditions on structural and digestive properties of the PSDCS is investigated. Relative humidity can alter the ordered structures of the PSDCSs due to changes in equilibrium moisture content. When fixing relative humidity at 33%, improvements in short‐range structure and long‐range crystalline structure of the PSDCS obtained at alternant temperature of 4/30 °C (12 h/12 h) are better than those of the PSDCSs obtained at other temperatures. The highest content of RS (29.97%) is found in the PSDCS obtained at 4/30 °C, which is approximately 3.3 times of native corn starch and 5.6 times of spray‐dried corn starch. These findings demonstrate feasibility of preparation of starch products with lower digestibility using spray drying combined with post‐treatments and lay the groundwork for the production and application of products with high content of RS.

A new dietary low-fat custard formulation made by waxy corn starch and xylitol: Rheological, sensory and in vitro digestibility investigation

Custard is a dairy starch-based dessert, in which presence of milk increases its nutritional value and sensitivity to freezing, pH, and storage. Producing a custard with less phase separation during storage and improving its functionality is challenging. The present study has investigated the effect of starch type (native corn starch and waxy corn starch), fat content (2.67% & 0.1%) and sucrose-xylitol ratio (1:0, 1:1, 0:1) on rheological, textural, enzyme digestibility and sensory properties of custard desserts. The back extrusion test showed a significant increase in consistency (40.60 mJ) by using xylitol and decreasing fat content compared to the control sample (2.16 mJ). Also, applying waxy corn starch diminished hardness (1.66 N) compared to the control (13.55 N), which was accompanied by a decrease of syneresis after five days of storage from 10.29% to 0.02% and improvement of sensory properties of creaminess, smoothness and taste intensity. Accordingly, low-fat custard formulation containing waxy corn starch and xylitol indicated high creaming stability (98.08%), adhesiveness (9.45 mJ), viscosity at a constant shear rate of 50 s−1 (3.58 Pa s), and water holding capacity after five days of storage at 4 °C (99.99%) and thickness (9.53). Also, xylitol reduced custards’ glucose release after amylase objection.

Characterization of Physicochemical Properties of Annealed Corn Flour and Starch: A Verification of Meta‐Analysis

AbstractThis study examines the effects of annealing process (temperature 50 °C, moisture content of 80%, for 20 h) on physicochemical characteristics (proximate composition, content of resistant starch (RS) and amylose, degree of starch digestibility, shape and size of starch granules, crystallinity, and starch gelatinization profile) of corn flour and corn starch. Two stages of experiment are as follows: 1) verifying the results of the meta‐analysis of corn starch and flour modification by annealing method and 2) analyzing their physicochemical properties. As a result, annealing significantly improves RS content in both groups, reaching 14.18% in annealed corn flour (AF) (compared to 3.27% in native corn flour (NF)) and 21.87% in annealed corn starch (AS) (compared to 3.82% in native corn starch (NS)). The present work also confirms that the treatment unaltered birefringence properties of all samples. Moreover, pasting properties of corn starch and flour demonstrate remarkable changes. The peak viscosity of AS and NS is higher than AF and NF. In addition, gelatinization seems to occur at similar temperature, but needs extra time for starting gelatinization. XRD analysis reveals A‐type crystalline for all samples, while FTIR analysis evidenced that annealing process alters the regions of amorphous and crystalline.

Effect of soybean polysaccharide and soybean oil on gelatinization and retrogradation properties of corn starch

This investigation stems from the wide interest in mitigating starch retrogradation, which profoundly impacts the quality of starch-based food, garnering significant attention in the contemporary food industry. Our study delves into the intricate dynamics of soluble soybean polysaccharide (SSPS) and soybean oil (SO) when added individually or in combination to native corn starch (NCS), offering insights into the gelatinization and retrogradation phenomena. We observed that SSPS (0.5 %, w/w) hindered starch swelling, leading to an elevated gelatinization enthalpy change (∆H) value, while SO (0.5 %, w/w) increased ∆H due to its hydrophobicity. Adding SSPS and/or SO concurrently reduced the viscosity and storage modulus (G′) of starch matrix. For the starch gel (8 %, w/v) after refrigeration, SSPS magnified water-holding capacity (WHC) and decreased hardness through hydrogen bonding with starch, while SO increased hardness with limited water retention. Crucially, the combination of SSPS and SO maximized WHC, minimized hardness, and significantly inhibited starch retrogradation. The specific ratio of SSPS to SO was found to significantly influence the starch properties, with a 1:1 ratio resulting in the most desirable quality for application in starch-based foods. This study offers insights for utilizing polysaccharides and lipids in starch-based food products to extend shelf life.

Comparative Evaluation of the Physico-Chemical Characterization of Native and Modified Starches from Jackfruit, Corn and Cassava as Potential Additives in Drilling Fluid

The physicochemical properties of starches determine their industrial application, and modification have shown further improvement on the properties of starch. Hence, the physicochemical properties of modified starches obtained from jackfruit were analyzed and compared with native jackfruit (JF), corn (MN) and cassava (CN) starches to determine their usability as additives in drilling fluid formulation. Starch from jackfruit pulp was chemically modified with two carboxymethylation methods (JC1 & JC2) and acetylation method (JA). The physicochemical properties were assessed using Scanning Electron Microscopy, Differential Scanning Calorimetry, Fourier transform infrared spectroscopy and Thermogravimetric analysis to determine their effectiveness to improve JF properties. The results revealed that at 90 °C, JC2 was found to have the highest swelling power and water holding capacity when compared with other modified and native starches. The result of the thermal properties of the starches showed that JC2 produced better thermal properties with the peak gelatinization temperature in the decreasing trend JC2>JC1>JF>MN>JA>CN. The SEM result showed that modification reduced the particle size of the starches thereby increasing the surface area of the starches for better reactivity than the native jackfruit, corn and cassava starches. The thermal stability of the starches showed that modification by carboxymethylation (JC1 and JC2) improved the stability of the starches while the reverse was the case for JA. In comparison with corn and cassava, the modified starches JC1 and JC2, performed excellently in all the properties analyzed. The possession of the highest swelling power, highest water holding capacity, highest thermal stability and excellent gelatinization temperature of 90 ℃ (Tp) places JC2 above other modification methods thereby making it a potential replacement for corn and cassava as an additive in drilling fluid formulation.

Effect of ultrasound-ethanol immersion, microwave and starch-blanching pretreatments on drying kinetics, rehydration, and quality properties of beetroot chips

Abstract For the first time, the impact of ultrasound-ethanol immersion as a non-thermal pretreatment (NTPT) and coating-blanching in starch solutions as a thermal pretreatment (TP) on the convective drying of beetroot was evaluated. The beetroot was exposed to ethanol immersion (E), ultrasound (U), and ultrasound-ethanol immersion (UE). Besides, TP pretreatment was performed by blanching the beetroot at steam (SB), water (WB), starch-coating solutions, and microwave (M). The hot air drying was conducted at 90 °C and air velocity of 1.2 m/s. The maximum decreases in the drying time were observed at UE30 (64.29 %) and the sample blanched at native corn starch solution (60.17 %). Moisture diffusion coefficients ranged from 0.851 to 2.312 × 10−9 m2/s. The friction drag force, convective heat, and mass transfer coefficients were 2.840 × 10−6 N, 59.368 W/m2 K, and 0.0492 m/s, respectively. The thermal conductivity, specific heat, and density ranged from 0.464 to 0.615 W/m. K, 3164–4071 J/kg. K, and 798.9 to 1055.9 kg/m3, respectively. The maximum values of rehydration ratio at non-thermal (NTPT) and thermal pretreatments (TP) were observed at U30 and the sample blanched at the modified starch solution (MCS), respectively. The total phenolic contents of the NTP sample decreased while those for the TP samples increased due to boosted polyphenol synthesis at high temperatures. Both U and E samples caused a decrease in the total antioxidant activity, while they increased the anthocyanin content of beetroot samples. Pretreatments reduced the hardness owing to changes in the microstructure of the sample. U, E, and M pretreatments increased the brightness of samples, and the minimum color change compared with control samples was observed by UE30 pretreatment. The UE and blanching at a starch solution could be selected for improving the drying characteristics of beetroots at an industrial scale.

Effect of solution on starch structure: New separation approach of amylopectin fraction from gelatinized native corn starch

The complete dissolution of starch without degradation are necessary prerequisites for starch fractionation to obtain amylose or amylopectin (AP). With the recent, continuous progress in finding efficient and eco-friendly starch-dissolving solutions, applying new solvents for starch fractionation is important. In this study, the effects of dimethyl sulfoxide (DMSO), NaOH, and CaCl2 solutions on starch structure and AP product parameters during starch fractionation were compared with respect to the starch deconstruction effect. This study proved that the CaCl2 solution could effectively dissolve corn starch (50 °C, solubility of 98.96 %), and promote the regeneration of starch into uniform and fine particles. Furthermore, the three solvents (DMSO, NaOH, and CaCl2) changed the crystal structure of corn starch, but they were all non-derivatizing solvents. The effect of the CaCl2 solution on the molecular structure of corn starch was the least significant of the three solvents. Finally, the extraction rate of AP from the CaCl2 solution reached 69.45 %. In conclusion, this study presents a novel and effective method for AP extraction.

Characterization of methyltetrahydrophthalic anhydride esterified corn starch and their ability in stabilizing Pickering emulsion

Methyltetrahydrophthalic anhydride (MeTHPA) esterified corn starches (MeCS) with degrees of substitution (DS) of 0.0066–0.072 were prepared, characterized and applied to stabilize Pickering emulsion. Fourier transform infrared spectroscopy analysis revealed the presence of a new ester group in MeCS. MeTHPA modification damaged the crystal structure of the corn starch, made its surface structure rough and irregular, and increased its contact angle. These changes were positively correlated with the DS of MeCS. Compared to native corn starch, the particle size of MeCS increased first and then decreased with an increase in DS, the lowest value (4.67 ± 0.08 μm) was observed for MeCS with highest DS (0.072). The stability of Pickering emulsions stabilized by MeCS with a DS of 0.072 was better than those stabilized by MeCS with lower DS (0.0066–0.019), which may attribute to their smaller particle size and higher viscosity. MeCS (DS 0.072) as emulsifiers at a concentration of 3% (w/v) could keep the emulsion stable even after 50 days of storage. This research suggested that MeCS at proper DS and concentration levels may serve as effective particle stabilizers for Pickering emulsions.

Preparation and characterization of biopolymer-based adsorbents and their application for methylene blue removal from wastewater

In the present study, four biopolymer-based materials consisting of native corn starch (CS), phosphate corn starch (PS), starch nanocrystals (SNCs), and phosphate corn starch nanocrystals (PSNCs) were synthesized and used for methylene blue (MB) removal as a function of various parameters, including initial MB concentration (C0, 10–500 mg L−1), adsorbent dosage (Cs, 0.02–0.15 g), contact time (t, 5–15 min), solution pH (2–11), and temperature (25–45 °C). The removal percentage of MB increased dramatically upon increasing the biopolymer dosage, temperature, and pH; while it decreased upon increasing the initial MB concentration. The adsorption behavior of biopolymer-based materials towards MB was found to be accurately described by the pseudo-second-order kinetic and Langmuir isotherm models. According to the Langmuir model, the maximum adsorption capacities of the adsorbents were ordered as follows: PSNCs (88.53 mg g−1) > SNCs (79.55 mg g−1) > PS (73.17 mg g−1) > CS (63.02 mg g−1). PSNCs was able to remove 96.8% and 76.5% of 20 mg L−1 MB in greywater and petrochemical wastewater, respectively, at an optimum pH of 9 and retained 86.42% of its usability even after five adsorption–desorption cycles. The analysis of the surface charge of the adsorbents before and after MB adsorption, combined with the FTIR spectrum of MB-saturated biopolymer-based materials, provided evidence that electrostatic interactions was the primary mechanism involved in the adsorption of MB. Meanwhile, hydrogen bonding and π–π interactions were found to have a minor contribution to the adsorption process. Based on the results, it can be inferred that PSNCs has promising potential as an adsorbent for the treatment of MB-containing wastewater, owing to its exceptional properties, which include high adsorption capacity, low cost, and applicability for multiple reuses.

Adsorption properties of corn starch modified by malt amylases and crosslinking agents: A comparison between sodium trimetaphosphate and organic acids

In order to investigate the effects of different crosslinking agents on physicochemical properties and adsorption properties of porous starch. Native corn starch was hydrolyzed by maltase and crosslinked with different crosslinking agents. Sodium trimetaphosphate crosslinked porous starch (STMP-MPS), malic acid cross-linked porous starch (MA-MPS) and citric acid cross-linked porous starch (CA-MPS) were prepared. After crosslinking, MA-MPS and CA-MPS showed a new CO stretching absorption peak at 1738 cm−1, and the crosslinking degree was much higher than that of STMP-MPS. The surface area of MA-MPS was 36 % higher than that of STMP-MPS. Compared with the average pore size of 12.43 nm of STMP-MPS, CA-MPS (14.02 nm) and MA-MPS (14.79 nm) were increased more significantly. The degradation temperature of MA-MPS and CA-MPS was increased by the introduction of ester bond, which indicates that the organic acid cross-linking strengthens the starch granules and hence more energy is required for disruption. Compared with STMP-MPS, the water absorption of MA-MPS and CA-MPS increased by 64 % and 32 %, respectively. Furthermore, the adsorption capacity of MA-MPS to essential oil was the strongest, about 4 times that of STMP-MPS. Overall, it is feasible to modify porous starch by crosslinking reaction to improve its heat resistance and adsorption properties.

Effect of operating conditions on structure and digestibility of spray-dried corn starch

Spray drying has been widely applied in food industry due to its efficiency and low cost. Exploring feasibility to prepare resistant starch (RS) via spray drying could open up new route to produce starch-based products with low glycemic index efficiently. In this study, effects of spray drying operating conditions on the structure and digestibility of recrystallized spray-dried corn starch (RSDCS) were explored. Apparent amylose content (AAC) and swelling power (SP) of the RSDCSs increased after the spray drying and recrystallization. Particle size of the RSDCSs decreased significantly with increase of compressed air flow and decrease of starch suspension concentration. Furthermore, the short-range order, long-range order, and content of RS in the RSDCSs decreased with increase of compressed air flow and starch suspension concentration. The Pearson's correlation analysis showed that digestive properties of the RSDCSs were mainly related to the short-range ordered structure and crystalline structure. Moreover, Mantel analysis revealed that operating conditions changed the digestibility of the RSDCSs through impacting crystalline structure, AAC and SP. The highest content of RS in the RSDCSs (23.08%) was increased near 2.6 times comparing to that of native corn starch (9.02%).

Thermo-mechanical and baking properties of the gluten free zein - starch doughs

Thermo-mechanical properties of doughs based on zein and different types of starch (native corn starch, modified corn starch and tapioca) were investigated in this study. The physical properties of the gluten free breads, prepared using the model zein – starch mixtures, were additionally determined. The Mixolab parameters measured while running the Chopin+ protocol indicated that the dough exhibited viscoelastic properties at 39°C, and not at 30°C as in the case of gluten system dough. The type of starch used in admixture with zein to prepare the dough significantly influenced the viscoelastic properties of the samples. The lowest starch retrogradation was obtained for the zein-modified corn starch mixture (C5-C4 of 0.55 Nm), while in case of the samples with native corn starch and tapioca the C5-C4 values were close to 0.74-0.79 Nm. The zein-tapioca sample had the lowest breakdown (C3-C4) of 0.22 Nm, followed by the zein-native corn starch sample, with C5-C4 of 0.53 Nm. Bread samples prepared with zein and native or modified corn starch at high water absorption levels (77% and 85%, respectively) had the highest specific volume values of 3.18 cm3/g and 2.22 cm3/g, respectively. These results indicate that zein can be successfully combined with starch from various sources for obtaining gluten free products.

Structural and Functional Properties of Porous Corn Starch Obtained by Treating Raw Starch with AmyM.

Porous starch is attracting considerable attention for its high surface area and shielding ability, properties which are useful in many food applications. In this study, native corn starch with 15, 25, and 45% degrees of hydrolysis (DH-15, DH-25, and DH-45) were prepared using a special raw starch-digesting amylase, AmyM, and their structural and functional properties were evaluated. DH-15, DH-25, and DH-45 exhibited porous surface morphologies, diverse pore size distributions and pore areas, and their adsorptive capacities were significantly enhanced by improved molecular interactions. Structural measures showed that the relative crystallinity decreased as the DH increased, while the depolymerization of starch double helix chains promoted interactions involving disordered chains, followed by chain rearrangement and the formation of sub-microcrystalline structures. In addition, DH-15, DH-25, and DH-45 displayed lower hydrolysis rates, and DH-45 showed a decreased C∞ value of 18.9% with higher resistant starch (RS) content and lower glucose release. Our results indicate that AmyM-mediated hydrolysis is an efficient pathway for the preparation of porous starches with different functionalities which can be used for a range of applications.

Thermoplastic starch (TPS)-based composite films for wastewater treatment: synthesis and fundamental characterization.

Modification of starch is a potential basic research aiming to improve its water barrier properties. The general purpose of this study is to manufacture cross-linked iodinated starch citrate (ISC) with a degree of substitution (DS) ≈ 0.1 by modifying native corn starch with citric acid in the presence of iodine as an oxidizing agent. Thermoplastic starch (TPS) was generated with urea as a plasticizer and blended with various concentrations of ISC of (2, 4, 6%) (wt/wt) to obtain (UTPS/ISC2, UTPS/ISC4, and UTPS/ISC6). Nanocomposite film was formed from UTPS/ISC2 in presence of stabilized iodinated cellulose nanocrystals UTPS/ISC2/SICNCs via gelatinization at a temperature of 80ºC. Water solubility and water vapor release were studied amongst the water barrier features. The fabricated starch-based composite films were evaluated utilizing Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electronic Microscope analysis (SEM), surface area, and tensile measurements. The adsorption of crystal violet (CV) dye onto produced samples was examined in an aqueous solution. The findings revealed that the UTPS/ISC2/ISCNCs has 83% crystal violet elimination effectiveness. Moreover, the adsorption isotherms were assessed and figured out to vary in the order of Langmuir > Temkin > Freundlich > Dubinin-Radushkevich.

Influence factors of starch nanoparticles formation and their application in Pickering emulsion

The native corn starch and corn amylose were used to prepared starch nanoparticles through two kinds of nanoprecipitation methods. The mainly property of these starch nanoparticles was the crystalline property, at the same time, the particle size, morphology, FT-IR spectra and contact angle of the starch nanoparticles were also investigated. Results showed that the mean size values of native corn starch nanoparticles were smaller than that of corn amylose nanoparticles prepared by the two methods. The nanoprecipitation methods had no significant difference on crystalline structure for all the starch nanoparticles, while the corn amylose nanoparticles prepared by dropping ethanol into the amylose paste had a higher crystallinity of 52.49%, and the water contact angle of which increased to 38.72° than that of corn amylose. Pickering emulsions stabilized by the above amylose nanoparticles showed a more concentrated particle size distribution and the nanoparticles could be well dispersed on the surface of the oil droplets. The results of this study demonstrated that corn amylose nanoparticles prepared by dropping ethanol into the amylose paste had a potential application in stabilizing Pickering emulsions.

Effect of ultrasound-microwave and microwave-ultrasound treatment on physicochemical properties of corn starch

Natural starch is an agricultural sourced biopolymer being low cost, biodegradable, high efficiently, renewable and easy available. Despite these advantages, phisochemical properties of native starch are limited for most industrial applications and must be modified. Ultrasound and microwave treatment have been widely applied separately for starch modification. Ultrasound treatment, with high efficiency and low cost, and microwave treatment, which produces homogeneous and high quality products, are short proceesing time technologies that can be used together to change the structure and properties of starches obtained from various plants. In this study the effects of ultrasound and microwave combined treatment on the physicochemical properties of natural corn starch were investigated. Corn starch was irritated using different combination of ultrasound-microwave and microwave-ultrasound treatment; using 90, 180, 360 and 600 W microwave power during 1, 2, 3 min, and using ultrasound at 35 °C constant temperature for 20, 30, 40 min. The structural changes of modified corn starches were determined by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) analyses. Nowadays, many physical methods are used for starch modification, but limited studies were on ultrasound-microwave and microwave-ultrasound combined treatment method. As a result of this study, it was observed that ultrasound and microwave combination is an efficient, fast and environmentally friendly method for natural corn starch modification.