Wheat Gluten Matrix Research Articles

The effects of maltodextrin/starch in soy protein isolate–wheat gluten on the thermal stability of high-moisture extrudates

This study aimed to investigate the interaction between maltodextrin/starch of different molecular weight distributions and soy protein isolate (SPI)–wheat gluten (WG) matrix during high-moisture extrusion. Two maltodextrins (dextrose equivalent (DE): 10 and 20) and wheat starch were extruded with SPI–WG blend in a system of 65, 70, and 75% moisture to investigate their effects on texture and thermal stability. Incorporating 5% maltodextrin (DE10) in the SPI–WG matrix improved the fiber structure and thermal stability. When wheat starch was thoroughly gelatinized during subsequent sterilization, the fiber structure and thermal stability were also improved. It was found that the plasticization caused by small-molecular weight saccharides and enhanced phase separation caused by large-molecular weight saccharides changed the melting temperature of blends and significantly improved the texture and thermal stability of extrudates.

Wheat gluten hydrolysates with embedded Ag-nanoparticles; a structure-function assessment for potential applications as wound sorbents with antimicrobial properties

Numerous approaches have been used to prevent bacterial infection from injured skin, such as bandages and topical creams. However, the higher level of reactive oxygen species, bacterial infections, and excess wound exudates remain the major challenges for wound healing. In this study, we have tailored the structure of wheat gluten hydrolysates (WGH) as a continuous matrix by compositing it with a minimal amount of PVA, PVP, and PEG as polymer crosslinkers (0.5 wt%) to provide film structure integrity. Silver nanoparticles (AgNPs) were impregnated into the WGH to develop a control release matrix of the AgNPs. Scanning electron microscopy, X-ray diffractogram, and functional group patterns of WG and AgNPs indicate a successful integration of AgNPs into the wheat gluten matrix. The swelling capacity of the films was tested at acidic, neutral, and basic pH and was found to be highest in WG/PEG/Ag at pH 9 with 389%. The gradual release of Ag+/AgNPs from the films significantly scavenged free radicals and increased the antibacterial activity with up to a 12 mm inhibition zone against Pseudomonas aeruginosa. According to these findings, WGH with AgNPs has been successfully cast in films with increased absorption capacity, free radicals scavenging, oxidant quenching, and antibacterial capabilities, along with the sustained release of silver ions. The results, therefore, show the potential of the developed films in biomedical applications such as wound dressing.

Research on a prolonged release system of urea powder potentially applied in sustainable agriculture

<p>A prolonged release system (SLIP) of urea powder encapsulated in a wheat gluten matrix was investigated as a sustainable substitute for use in agriculture with the goal of lowering nitrogen losses in the soil. Thermogravimetry (TGA), Fourier Transform Infrared Spectroscopy (FT-IR), and Scanning Electron Microscopy (SEM) were the methods used to characterize SLIP. The urea release kinetics in water were then assessed. Very porous structures were produced, the thermal stability of SLIP was noted, and interactions between urea and gluten proteins through hydrogen bonds were verified. According to the kinetics, urea was released at a high rate (38%) in the first ten minutes and reached the diffusion equilibrium (86.35%) after 36 hours. There is a chance that urea SLIP will be employed as a sustainable substitute in agriculture.</p>

Utilization of brown alga (Sargassum plagiophyllum) as an efficient reinforcement material for application in wheat gluten biocomposites

AbstractIn this work, brown alga (Sargassum plagiophyllum) was utilized as a reinforcement material to produce wheat gluten (WG) biocomposites. The effect of brown alga powder (BP) content and sonication treatments of BP on the properties of the obtained WG biocomposites were characterized. Adding 1 wt% BP to WG increased the tensile strength by 77% compared to neat WG and could delay the degradation process of the WG biocomposites due to the good interaction between BP and the WG matrix. When the time and amplitude of BP sonication was increased, the tensile strength of the obtained WG biocomposites slightly decreased, but still remained higher than the tensile strength of the neat WG. Therefore, this work presents an efficient reinforcement material and a potential treatment process to produce promising alternative biocomposites for the production of environment friendly materials.

Superabsorbent and Fully Biobased Protein Foams with a Natural Cross-Linker and Cellulose Nanofibers.

The development of fully natural wheat gluten foams showing rapid and high uptake of water, sheep blood, and saline solution, while maintaining high mechanical stability in the swollen state, is presented. Genipin was added as a natural and polar cross-linker to increase the polarity of the protein chains, whereas cellulose nanofibers (CNFs) were added as a reinforcement/stiffener of the foams, alone or in combination with the genipin. The presence of only genipin resulted in a foam that absorbed up to 25 g of water per gram of foam and a more than 15 g uptake in only 8 min. In contrast, with CNF alone, it was not possible to maintain the mechanical stability of the foam during the water uptake and the protein foam disintegrated. The combination of CNF and genipin yielded a material with the best mechanical stability of the tested samples. In the latter case, the foam could be compressed repeatedly more than 80% without displaying any structural damage. The results revealed that a strong network had formed between the wheat gluten matrix, genipin, and cellulose in the foam structure. A unique feature of the absorbent/foam, in contrast to commercial superabsorbents, was that it was able to rapidly absorb nonpolar liquids (here, n-heptane) due to the open-cell structure. The capillary-driven absorption due to the open-cell structure, the high liquid absorption in the cell walls, and the mechanical properties (both in dry and swollen states) of these natural foams make them interesting as a sustainable replacement for a range of petroleum-based foam materials, including absorbent hygiene products such as sanitary pads.

Surface-treated oil palm empty fruit bunch fiber improved tensile strength and water resistance of wheat gluten-based bioplastic

This study evaluated the morphology, chemical composition and color parameters of oil palm empty fruit bunch (OPEFB) fiber after surface treatment with hot water (90 °C) and alkali treatments (1 w/v% and 5 w/v% NaOH). Treatment of the fiber with a 5 w/v% solution of NaOH more effectively eliminated residual surface contaminants than hot water treatment and alkaline treatment with 1 w/v% NaOH. However, color parameters were slightly reduced. The tensile strength and water absorption of composites of wheat gluten and surface-modified fiber were compared with the same properties of composites loaded with unmodified fiber. The highest tensile strength and lowest water absorption were obtained with a composite of wheat gluten and 15 wt% OPEFB fiber treated with 5 w/v% NaOH. The good adhesion between the fiber and the wheat gluten matrix enabled a more effective transfer of stress from the wheat gluten matrix to the fiber and also reduced water absorption into the wheat gluten matrix. Therefore, composites of wheat gluten and oil palm empty fruit bunch fiber have potential to be developed for use as green composite materials.

Effect of kaolin content and sonication on the properties of wheat gluten composites

Wheat gluten composites with kaolin were prepared using compression molding, in the presence of glycerol as a plasticizer. The influences of kaolin content (0, 2.5, 5.0, 7.5, 10, 12.5 and 15.0 wt%) and probe sonication on the water resistance, degradation, mechanical, thermal and morphological properties of a wheat gluten-based bioplastic was investigate. The results showed that the mechanical properties of the wheat gluten-based bioplastic were significantly improved by the incorporation of kaolin. Scanning electron microscope (SEM) images revealed that, in comparison with a wheat gluten composite containing the same amount of non-sonicated kaolin, sonication effectively improved the dispersion of kaolin in the wheat gluten matrix, increasing tensile strength, thermal stability and water resistance. Also, sonicated kaolin could delay the degradation process of the wheat gluten-based bioplastic, indicating the potential agricultural application of these composites in the controlled release of the active contents of fertilizers.

Effect of adding a reactive plasticizer on the mechanical, thermal, and morphology properties of nylon toughened wheat gluten materials

ABSTRACTBlends of wheat gluten (WG) with up to 30% aliphatic nylon were prepared by mixing in 70% aqueous ethanol solution at 110 °C in a sealed reactor. After solvent removal and mechanical milling, rigid plaques were compression molded from the powdered blends. The microstructure of the molded plaques was studied via scanning electron microscopy. All compositions showed a phase separated morphology with seemingly poor compatibility between the two components. Up to 10% addition, the nylon was dispersed within the gluten matrix as discrete particles with an average diameter >10 μm. At higher nylon volume fractions there was evidence for the presence of gluten sub‐inclusions within the nylon phases. The dispersion of particles in a blend containing 10% nylon was improved and the particle size was decreased to roughly 5 μm by addition of an epoxy functionalized ethylene glycol oligomer. The additive simultaneously lowered the modulus of the WG matrix and appeared to improve the interfacial bonding between the gluten and the nylon. In cross‐sections of the ternary blends, fine filaments were observed spanning the gluten/nylon phases at the phase boundary. The compression molded plaques continued to exhibit brittle failure in mechanical bending tests characteristic of glassy gluten materials, however, the mechanical toughness was boosted to almost three times that of reference gluten plaques by the combined addition of the nylon and reactive plasticizer. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45931.

Preparation and properties of wheat gluten based bioplastics with fish scale

The objective of this study was to prepare the wheat gluten based bioplastics with fish scale (FS) through compression molding. The tensile strength of the wheat gluten/FS composites (the range of 6.5–7.5 MPa) was higher than that of the neat wheat gluten-based bioplastic (3.40 MPa). There was a good dispersion of the fish scale powder embedded within the wheat gluten matrix. Dynamic mechanical analysis results showed that the tan delta max peak height and storage modulus of the wheat gluten-based bioplasic was reduced by adding the fish scale. Moreover, the addition of the fish scale caused a weight loss and the surface of the wheat gluten based bioplastic after 120 h of accelerated weathering were differed from the neat wheat gluten based bioplastic. These results may help to find a new applications for fish scale waste to control the degradation rate of a wheat gluten based bioplastic in the agricultural field.

Structure and properties of biodegradable wheat gluten bionanocomposites containing lignin nanoparticles

Lignin nanoparticles (LNPs), prepared through precipitation from an ethylene glycol solution by using diluteacidic aqueous solutions, were obtained. Fourier transform infrared spectroscopy confirmed the removal of hemicelluloses from pristine lignin by acidolysis, while the TGA analysis revealed a retained thermal stability of the nanoparticles with respect of pristine lignin. The lignin nanoparticles presented a uniform size distribution and good stability at various aqueous pH mediums. Wheat gluten (WG) bionanocomposites filled with 0, 1 and 3% wt. of LNPs were produced and thermally and mechanically characterized by means of TGA, modulated DSC and DMTA analysis. UV–Vis spectroscopy and water sensitivity measurements were also performed, in order to fully characterize the produced materials. The results indicated that LNPs could also effectively absorb ultraviolet spectrum and improve the water sensitivity of WG bionanocomposites. Moreover, even if the addition of LNPs reduced the transparency at the two different weight contents, it enhanced the mechanical behavior and thermal stability of resulted bionanocomposites. A strong interaction between LNPs and WG matrix, as well as homogeneous distribution of LNPs within the WG matrix, was confirmed by FESEM investigation and mechanical characterization. The reduction of absorbed water as well as the increase in glass transition suggested that LNPs can be beneficial to enlarge the potential applications for WG based materials and confirmed the great potential of using these novel nanofiller in bio-based matrices.

Thermomechanical and Morphological Properties of Nanocomposite Films from Wheat Gluten Matrix and Cellulose Nanofibrils

The aim of this investigation was the optimization of preparing gluten film containing cellulose nanofibrils (CNF). An optimization procedure using central composite design (CCD) with three factors (CNF, glycerol, and sodium dodecyl sulfate (SDS) concentrations) was used in order to investigate the effect of these parameters on the mechanical (tensile strength--TS, elongation at break--ε(b)) and thermal properties of gluten films and to establish a formulation to depict the relationship between the mentioned factors and mechanical properties. Through regression analysis, it was found that TS and ε(b) well fitted by quadratic polynomial equations (R² = 0.99 and 0.98, respectively) and the glycerol concentration was the most significant factor influencing them. The optimization was based on maximizing TS and ε(b). The optimum conditions determined using response surface methodology (RSM) were defined as: CNF concentration, 11.129 g/100 g, glycerol concentration, 35.440 g/100 g and SDS concentration, 6.259 g/100 g. The predicted responses for these film preparation conditions were a TS of 3.630 MPa and ε(b) of 86.033%. The verification experiments were conducted under optimal conditions to compare predicted and actual values of dependent variables. This experiment indicated that both predicted and actual values (TS of 3.721 MPa and ε(b) of 88.935%) almost coincide each other and therefore the estimated models were reasonable and of high accuracy to predict dependent variables values. The scanning electron microscopy (SEM) images showed non-agglomerated and well dispersed CNF in the gluten matrix. Differential scanning calorimetry (DSC) results indicated that there is not any significant difference (P > 0.05) between the glass transition temperature (T(g)) of optimum nanocomposite (-29.12 °C) and control film (-29.64 °C) and their thermogravimetric analysis (TGA) thermograms showed similar degradation behavior.

Toughened wheat gluten and treated coconut fiber composite

The aim of the present work is to fabricate a biodegradable composite with improved mechanical properties and high work to failure by combining toughened wheat gluten matrix with 15 mass% surface treated, highly ductile coconut fiber. Matrix cracking at a flexural stress of 46MPa in wheat gluten was delayed until nearly 71MPa in the composite, with ultimate stress greater than 105MPa. Flexural stiffness was improved from roughly 4GPa in the wheat gluten to 5.4GPa in the composite. The work to failure was improved from 0.26MJ/m3 in wheat gluten to 1.45MJ/m3 with the toughened wheat gluten, and finally to 4.94MJ/m3 for the composite. The toughening additive for the wheat gluten was shown to “erase” aging effects in the wheat gluten but also appeared to change the interfacial characteristics.

Green composites based on wheat gluten matrix andposidonia oceanicawaste fibers as reinforcements

In this work, green composites from renewable resources were manufactured and characterized. A fibrous material derived from Posidonia oceanica wastes with high cellulose content (close to 90 wt% o ...

Nanostructured Silica/Wheat Gluten Hybrid Materials Prepared by Catalytic Sol–Gel Chemistry

AbstractThe main physicochemical properties of nanostructured silica/wheat gluten hybrid composites are presented. The extraction experiments suggest that the protein phase is intimately encased within the silica matrix, with silica–protein interactions driven by hydrogen bonding, as indicated by IR spectra. Spectroscopic results also show that silica induces a higher degree of constraint of the wheat gluten matrix, despite less aggregation. Moisture diffusion properties of the hybrid materials are investigated by a combined “desorption/sorption” approach. While the reduction of the moisture diffusivity in the presence of silica can be described by the geometrical impedance of a “sintered” porous solid, a time‐dependent relaxation/restructuring of the composite apparently occurs during the sorption‐desorption cycle.magnified image

Investigating the biodegradation pattern of an ecofriendly pesticide delivery system based on wheat gluten and organically modified montmorillonites

An organically modified montmorillonite (C30B) was introduced within a wheat gluten (WG)-based formulation containing ethofumesate (as model pesticide) with the aim to enhance its slow release properties by modulating both biodegradation and release properties. For this purpose, biodegradation pattern in soil and release properties in model system have been investigated for ethofumesate alone, WG-ethofumesate and WG-C30B-ethofumesate formulations. Respirometric experiments undertaken with ethofumesate in soil have evidenced a non-biodegradable behavior whereas the incorporation of 0.26% of ethofumesate in WG-based formulation did not affect the final biodegradability of WG-based material in spite of a slight but significant delayed biodegradation pattern. This delaying effect, attributed to the ecotoxic effect of ethofumesate, was shown to disappear when introducing C30B in the formulation. The use of WG-based materials to formulate ethofumesate also resulted in a slow release effect (in water) that could be significantly enhanced by adding organoclays in the materials in spite of a very poor dispersion of the nanoclays within the matrix. Indeed, the presence of clay aggregates evidenced by TEM in the WG matrix would result in the entrapment of ethofumesate taking into account the huge affinity of this pesticide for this nanoclay. This hypothesis appeared fully consistent with the assumption that ethofumesate would be less available to reduce microorganisms respiration and also potentially less subjected to transport mechanisms. As a result, WG-based formulations appeared as a suitable ecofriendly strategy to design slow release delivery system for pesticides with the objective to reduce pesticide leaching in the environment.

How the biodegradability of wheat gluten-based agromaterial can be modulated by adding nanoclays

The objective of this work was to investigate the influence of clay nanoparticles on the biodegradability of wheat gluten-based materials through a better understanding of multi-scale relationships between biodegradability, water transfer properties and structure of wheat gluten/clay materials. Wheat gluten/clay (nano)composites materials were prepared via bi-vis extrusion by using an unmodified sodium montmorillonite (MMT) and an organically modified MMT. Respirometric experiments showed that the rate of biodegradation of wheat gluten-based materials could be slowed down by adding unmodified MMT (HPS) without affecting the final biodegradation level whereas the presence of an organically modified MMT (C30B) did not significantly influence the biodegradation pattern. Based on the evaluation of the water sensitivity and a multi-scale characterization of material structure, three hypotheses have been proposed to account for the underlying mechanisms. The molecular/macromolecular affinity between the clay layers and the wheat gluten matrix, i.e. the ability of both components to establish interactions appeared as the key parameter governing the nanostructure, the water sensitivity and, as a result, the overall biodegradation process.

Biopolymer composites of wheat gluten with silica and alumina

Two composite systems were explored to assess the effect of particle dispersion on the properties of filled wheat gluten composites. Nanosilica particles and micro-alumina particles were combined with several silane coupling agents by various methods to perform a broad brush survey of chemical and physical interactions. Thermo-gravimetric analysis (TGA) was used to assess surface coverage on coated particles. Electron microscopy (scanning and transmission) techniques were used to assess particle dispersion and surface interactions. Producing the silica particles in the wheat gluten matrix led to better physical properties, as measured by 3-point bending, than producing the silica particles first, and then mixing them into the wheat gluten. Similarly, coating the alumina particles with silane coupling agents in the wheat gluten matrix led to better mechanical properties than first coating the alumina with silane and then mixing the coated particles into the wheat gluten.

Influence of processing temperature on the water vapour transport properties of wheat gluten based agromaterials

The influence of processing conditions (thermoforming temperature) on water vapour transport properties (permeability, sorption and diffusion) of wheat gluten-based films was studied in relation to structural properties (cross-linking degree of the wheat gluten matrix). Increasing temperature from 80°C to 120°C led to a significant decrease in material swelling in high moisture environment and a WVP reduction mainly due to a decrease in diffusivity but without important effect on the moisture sorption isotherms. This was attributed to a higher cross-linking degree of protein network for film thermoformed at 120°C, with a limited mobility and less possibilities of rearrangement in high moisture conditions.

A Comparison Study of Wheat Gluten Composites Filled with Dialdehyde Starch and Native Starch

Environmentally friendly green composites were prepared by blending Wheat gluten (WG) as matrix, dialdehyde starch (DAS) as filler and glycerol as plasticizer followed by compression molding of the mixture at 110 °C. The properties of the WG/DAS composite are compared with those of the WG/native wheat starch (NWS) composites. While tensile strength and strain at break decrease with increasing NWS content in the WG/NWS composites, a small content of DAS could improve tensile strength and strain at break simultaneously in the WG/DAS composites. The WG/DAS composites exhibit reduced moisture absorption in comparison with the WG/NEW composites. Formation of chemical bonding between DAS and WG is beneficial for the dispersion of DAS in the WG matrix and WG/DAS composites exhibit improved mechanical properties and reduced moisture absorption over the WG/NWS composites.

Wheat gluten-based renewable and biodegradable polymer materials with enhanced hydrophobicity by using epoxidized soybean oil as a modifier

Epoxidized soybean oil (ESO) was applied as an additive for wheat gluten (WG) to modify the properties of the renewable and biodegradable natural polymer materials. Optimum intermolecular interactions and crosslinking between ESO chains and the WG matrix were achieved under alkaline conditions. The WGESO materials were heterogeneous on a scale of 20–30 nm, but the homogeneity was improved upon increasing the amount of glycerol as a plasticizer in the materials. The combination of plasticization and crosslinking effects derived from ESO resulted in good retention in mechanical strength for the plasticized WGESO materials as compared to those without 10 wt % of mobile ESO additives. The hydrophobicity of the plasticized WG materials was also enhanced significantly by using the ESO additives.