Preparation of oxidized corn starch in dry method assisted by kneader

In this study, oxidized starch (OCS) with different carboxyl content was prepared by the dry method, with H2O2 as the oxidant and CuCl2 as the catalyst. The optimum conditions were obtained by an orthogonal experiment, under the carboxyl and carbonyl content of 0.6813 and 1.0416% respectively. Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction and gel permeation chromatography characterized the structures of OCS, and the thermal, gelatinization, viscosity property and its viscosity stability were measured. The results demonstrated that the crystallinity decreased slightly and the A-type crystal remained unchanged after oxidation, and the molecular weight of OCS decreased greatly. The thermal decomposition temperature, apparent viscosity and setback viscosity also decreased. With the increase of carboxyl content in OCS, the cold-water solubility and paste transparency of OCS paste increased gradually, while the viscosity of OCS paste decreased, and the viscosity stability displayed a trend of first increasing and then reducing. The OCS obtained by a kneader had low solution viscosity and high viscosity stability, suitable for sizing high count warp yarns.

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Activation of Corn Starch and Effect of the Activation on its Reactivity

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.549.183 ◽

2012 ◽

Vol 549 ◽

pp. 183-187 ◽

Cited By ~ 1

Author(s):

Yan Wang ◽

Jia Ying Xin ◽

Tie Liu ◽

Kai Lin ◽

Chao Yue Zhang ◽

...

Keyword(s):

Particle Size ◽

Water Solubility ◽

Corn Starch ◽

Cold Water ◽

Molecular Level ◽

Chemical Reactivity ◽

Level Structure ◽

Average Particle Size ◽

Average Particle ◽

Structure And Morphology

Native corn starch (NS) was activated by treatment with NaOH /Urea /H2O solution at low temperature to improve its chemical reactivity. Effects of the activation on the molecular level structure and morphology of the corn starch were investigated by mean of SEM. It was found that the average particle size of activated corn starch (AS) decreased to nanometer level, smaller than those of NS. The cold water solubility (CWS) has been increased from 0.45% to 96.4%. Effects of the activation on reactivity of the corn starches were investigated by analyzing the influences of the activation on degrees of substitutions (DS) of the esterifications. The DS of AS was higher than that of NS, from 0 to 0.1578, which indicated that NaOH/urea activation enhanced the chemical reaction activity of corn starch.

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Preparation and characterization of corn starch/PVA/glycerol composite films incorporated with ε-polylysine as a novel antimicrobial packaging material

e-Polymers ◽

10.1515/epoly-2020-0019 ◽

2020 ◽

Vol 20 (1) ◽

pp. 154-161 ◽

Cited By ~ 2

Author(s):

Gao Yurong ◽

Li Dapeng

Keyword(s):

Water Solubility ◽

Corn Starch ◽

Composite Films ◽

Antimicrobial Properties ◽

Xrd Analysis ◽

Sem Analysis ◽

Packaging Material ◽

Hydroxyl Group ◽

Electron Microscopic ◽

Antimicrobial Packaging

AbstractCorn starch/polyvinyl alcohol (PVA)/glycerol composite films incorporated with ε-polylysine were prepared, and their properties were investigated. The Fourier-transform infrared (FTIR) spectroscopy indicated that the interactions happened between the amino group of ε-polylysine and hydroxyl group starch/PVA composite films. X-ray diffraction (XRD) analysis showed that the addition of ε-polylysine decreased the intensity of all crystal peaks. Thermogravimetric (TGA) analysis suggested that ε-polylysine improved the thermal stability of composite films. Scanning electron microscopic (SEM) analysis showed that the upper surface of composite films incorporated with ε-polylysine presented more compact and flat surface. The antimicrobial activity of the composite film progressively increased with the increasing of ε-polylysine concentration (P < 0.05). The tensile strength, elongation at break and water absorption significantly increased, whereas water solubility decreased with the increasing of ε-polylysine concentration (P < 0.05). Therefore, the corn starch/PVA/glycerol composite films incorporated with ε-polylysine had good mechanical, physical and antimicrobial properties and could have potential application as a novel antimicrobial packaging material.

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Cold-water solubility, oil-adsorption and enzymolysis properties of amorphous granular starches

Food Hydrocolloids ◽

10.1016/j.foodhyd.2021.106669 ◽

2021 ◽

Vol 117 ◽

pp. 106669

Author(s):

Chenlu Fang ◽

Junrong Huang ◽

Huayin Pu ◽

Qi Yang ◽

Zhiguang Chen ◽

...

Keyword(s):

Water Solubility ◽

Cold Water ◽

Oil Adsorption

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Alternative Tanning Agent for Leather Industry from a Sustainable Source

Journal of the American Leather Chemists Association ◽

10.34314/jalca.v116i3.4249 ◽

2021 ◽

Vol 116 (3) ◽

Author(s):

Cigdem Kilicarislan Ozkan ◽

Hasan Ozgunay

Keyword(s):

Molecular Weight ◽

Corn Starch ◽

Periodate Oxidation ◽

Gel Permeation Chromatography ◽

Proton Nuclear Magnetic Resonance ◽

Resonance Spectroscopy ◽

Leather Industry ◽

Sodium Metaperiodate ◽

Gel Permeation ◽

Aldehyde Content

Dialdehyde starches with different aldehyde content from native corn starch were prepared by sodium periodate oxidation to be used as a tanning agent in leather making. For this purpose, native corn starch was oxidized with sodium metaperiodate in different molar ratios. After oxidation processes, the yields, solubility in water and aldehyde contents of the obtained dialdehyde starches were determined as well as structure characterizations by Proton Nuclear Magnetic Resonance Spectroscopy, Fourier Transform Infrared Spectroscopy and Gel Permeation Chromatography. Evaluating the gel permeation chromatography data, the dialdehyde starch samples which were thought to be in appropriate molecular weight/size to penetrate into skin fibers were selected to be used in the tanning process. Their tanning abilities were evaluated by investigating hydrothermal stabilities, filling and fiber isolation characteristics and physical properties determined by mechanical tests and organoleptically. From the evaluation of the results, it was revealed that sodium metaperiodate oxidized starches which have appropriate molecular weight and adequate aldehyde content has a remarkable tanning effect and can be utilized as a tanning agent with the advantages of not necessitating pickling process which means saving time and simplifying the production but more importantly offering an important advantage from an environmental point of view.

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Poly(2,6-diphenyl-1,4-phenyl oxide): Characterization by gel-permeation chromatography, light scattering, and solution viscosity

Journal of Polymer Science Part A-2 Polymer Physics ◽

10.1002/pol.1972.160100207 ◽

1972 ◽

Vol 10 (2) ◽

pp. 273-282 ◽

Cited By ~ 2

Author(s):

A. R. Shultz ◽

A. L. Bridgman ◽

E. M. Hadsell ◽

C. R. McCullough

Keyword(s):

Light Scattering ◽

Gel Permeation Chromatography ◽

Solution Viscosity ◽

Gel Permeation

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Preparation of starch phosphate carbamides and its application for improvement of noodle quality

Czech Journal of Food Sciences ◽

10.17221/159/2019-cjfs ◽

2019 ◽

Vol 37 (No. 6) ◽

pp. 456-462 ◽

Cited By ~ 5

Author(s):

Yaojun Sun ◽

Shengru Yang ◽

Guanglei Li ◽

Mengxing Li

Keyword(s):

Corn Starch ◽

High Viscosity ◽

Pasting Properties ◽

Gelatinization Temperature ◽

Dry Process ◽

Starch Derivatives ◽

Major Factors ◽

Phosphate Salts ◽

Quadratic Models ◽

Viscosity Stability

Phosphorylated corn starch derivatives show improved pasting properties compared to native corn starch. In this study, starch phosphate carbamides (SPC) were prepared through a dry process reaction of starch with urea and phosphate salts. The effects of major factors on SPC pasting properties were studied by response surface methodology. Validation results showed that the polynomial quadratic models were adequate for predicting SPC pasting properties. Fourier transform infrared spectroscopy (FTIR) and a Rapid Visco Analyzer (RVA) were used to characterize SPC. RVA results showed SPC had higher peak viscosity, trough, breakdown, setback and final viscosities and lower gelatinization temperature compared to native starch. FTIR showed the characteristic absorption of the ester phosphate group in SPC at 1244/cm. SPC with high viscosity stability were applied to replace part of wheat flour used for making noodles. The best quality noodles were obtained with 12% SPC substitution.

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Drum drying process of jabuticaba pulp using corn starch as an additive

BRAZILIAN JOURNAL OF FOOD TECHNOLOGY ◽

10.1590/1981-6723.16619 ◽

2020 ◽

Vol 23 ◽

Author(s):

Larissa Peixoto Nunes ◽

Cristhiane Caroline Ferrari ◽

Danielle Ito ◽

Elaine de Cássia Guerreiro Souza ◽

Silvia Pimentel Marconi Germer

Keyword(s):

Sorption Isotherm ◽

Water Solubility ◽

Corn Starch ◽

Gravimetric Method ◽

Storage Condition ◽

Good Alternative ◽

Total Phenolic ◽

Drum Drying ◽

Monolayer Moisture ◽

Drying Conditions

Abstract Jabuticaba is a fruit native to Brazil, appreciated for its flavor and is also very nutritious, but it is a seasonal fruit and highly perishable. Therefore, drying is a good alternative for its conservation. The purpose of this work was to use drum drying to obtain jabuticaba flakes using corn starch as the main carrier agent. The sorption isotherm of the flakes at 25 °C was also studied, as well as the determination of the critical storage condition and the estimation of product shelf life through the permeability of different packages to the water vapor using mathematical models. The drum drying conditions were: temperature of 144 °C; residence time of 18 seconds; addition of 20% (dry basis) of corn starch and 0.5% (d.b.) of glyceryl monostearate. The final product was analyzed with respect to its physicochemical and technological properties. The sorption isotherm of the flakes was determined at 25 °C, using the gravimetric method with saturated solutions (0.11 ≤ aw ≤ 0.84). After the process, the flakes presented good retention of anthocyanins and total phenolic compounds, besides a high antioxidant activity. The water solubility of the product was around 70% and the hygroscopicity was approximately 24%. The equilibrium experimental points of the isotherm were better adjusted by the GAB model, with a monolayer moisture value of 12.74% (w.b) and a critical aw of 0.432.

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Photonic crystals obtained by soap-free emulsion terpolymerization

Open Chemistry ◽

10.2478/s11532-013-0356-7 ◽

2014 ◽

Vol 12 (1) ◽

pp. 126-130

Author(s):

Edina Rusen ◽

Aurel Diacon ◽

Alexandra Mocanu

Keyword(s):

Homogeneous Nucleation ◽

Water Solubility ◽

Gel Permeation Chromatography ◽

Nucleation Mechanism ◽

Hydroxyethyl Methacrylate ◽

System A ◽

Vis Spectroscopy ◽

Gel Permeation ◽

Nucleation Mechanisms ◽

Generating System

AbstractThis paper presents the use of soap-free emulsion terpolymerization to obtainphotonic crystals (PCs). Monodisperse latexes resulted from the polymerization of styrene (ST) with 2-hydroxyethyl methacrylate (HEMA) and acrylic acid (AA) at different compositions defined as system A, B and C respectively. The water solubility of the macroradicals determined different nucleation mechanisms in all three cases. The micellar nucleation mechanism was more predominant for generating system A, whereas the homogeneous nucleation was specific for system C. For system B, both nucleation mechanisms werepossible with the same probability. The latexes and the resulted PCs were characterized by optical microscopy (OM), dynamic light scattering (DLS), gel permeation chromatography (GPC) and UV-VIS spectroscopy.

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Reinforcement of Thermoplastic Corn Starch with Crosslinked Starch/Chitosan Microparticles

Polymers ◽

10.3390/polym10090985 ◽

2018 ◽

Vol 10 (9) ◽

pp. 985 ◽

Cited By ~ 7

Author(s):

Diana Paiva ◽

André Pereira ◽

Ana Pires ◽

Jorge Martins ◽

Luísa Carvalho ◽

...

Keyword(s):

Water Solubility ◽

Corn Starch ◽

Polymer Network ◽

Xrd Analysis ◽

Thermoplastic Starch ◽

Interpenetrating Polymer Network ◽

Melt Mixing ◽

Chitosan Microparticles ◽

Polysaccharide Composition ◽

Low Solubility

Microparticles of corn starch and chitosan crosslinked with glutaraldehyde, produced by the solvent exchange technique, are studied as reinforcement fillers for thermoplastic corn starch plasticized with glycerol. The presence of 10% w/w chitosan in the microparticles is shown to be essential to guaranteeing effective crosslinking, as demonstrated by water solubility assays. Crosslinked chitosan forms an interpenetrating polymer network with starch chains, producing microparticles with a very low solubility. The thermal stability of the microparticles is in agreement with their polysaccharide composition. An XRD analysis showed that they have crystalline fraction of 32% with Va-type structure, and have no tendency to undergo retrogradation. The tensile strength, Young’s modulus, and toughness of thermoplastic starch increased by the incorporation of the crosslinked starch/chitosan microparticles by melt-mixing. Toughness increased 360% in relation to unfilled thermoplastic starch.

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