The effects of ultrasonic/microwave assisted treatment on the properties of soy protein isolate/titanium dioxide films

Assessment of the impact of quinoa protein modification on silver carp surimi gel quality and its utilization in 3D printing

This study aims to investigate the effects of different modified quinoa proteins (MQP) on the gel quality of silver carp surimi, as well as to explore their feasibility for three-dimensional (3D) printing. Five different methods were employed to modify quinoa protein, water bath (WB), microwave (MW), ultrasonic (US), microwave followed by ultrasonic (M-U), and ultrasonic followed by microwave (U-M), to prepare compound surimi gels (MQPs). The results showed that the addition of quinoa protein improved the gel quality of surimi, while the MQP had an even better effect on enhancing the gel quality. Among them, QP modified by US exhibited a smoother surface, with an expressible water content of 9.78%, gel strength of 22.26 N·mm, and hardness of 27.59 N. The addition of all MQP reduced the cooking loss of surimi, promoted the formation of bound water, and enhanced the G' and G″ values of MQPs. The characterization of MQP based on molecular driving force revealed that the addition of MQP enhanced the hydrophobic interactions within the surimi gel. This improvement is attributed to the structural changes in quinoa protein induced by the modification process, where the exposure of a large number of hydrophobic groups to water facilitated the formation of a more uniform network structure among the surimi proteins. Additionally, feasibility research on 3D printing of compound products was conducted, revealing that all MQPs exhibited good support and surface smoothness, making them suitable for applications in the field of food 3D printing. PRACTICAL APPLICATION: This study investigated the effects of quinoa protein addition on the physical properties and mechanism of silver carp surimi under different modification methods, as well as the feasibility of 3D printing. The results demonstrated that incorporating modified quinoa protein improved the quality of the surimi gel. This research expands the range of surimi products and provides a theoretical foundation for the development and production of plant protein-surimi compound products. Additionally, it contributes theoretical insights into the characteristic application of quinoa protein.

Soy Protein/Polyvinyl-Alcohol (PVA)-Based Packaging Films Reinforced by Nano-TiO2

This work was investigated to prepare a reinforcing composite packaging film composited of soy protein/polyvinyl alcohol (PVA) and nano-TiO2. First, different film compositions were designed by the particle size of nano-TiO2, concentration of nano-TiO2, concentration of polyvinylpyrrolidone (PVP, a dispersing agent for nano-TiO2), and pH of film casting solution. Then, the film composition that yielded the optimal physical properties was identified using orthogonal array design single-factor experiments, considering its physical properties, including tensile strength, elongation, water absorption, water vapor transmission, oxygen permeation, thermal property, and film morphology. The results displayed that the optimal film composition was (1) soy protein/PVA film with 2.5 wt% nano-TiO2, (2) 30 nm nano-TiO2 particle size, (3) 1.5 wt% PVP, and (4) pH 6.0 of film-forming solution. It yielded tensile strength of 6.77 MPa, elongation at break rate of 58.91%, and water absorption of 44.89%. Last, the films were characterized by scanning electron microscope (SEM) and differential scanning calorimetry (DSC). SEM analysis showed that compared with the film without TiO2, the film containing TiO2 has a smoother surface, and DSC determined that adding nano-TiO2 can improve the thermostability of soy protein/PVA film. Therefore, the film prepared in this paper is expected to provide a new theoretical basis for use in the packaging industry.

Effects of the geometry of reinforcement on physical properties of sodium caseinate/TiO2 nanocomposite films for applications in food packaging

Plastic materials for food packaging are being replaced by biodegradable films based on biopolymers due to the adverse effects they have had on animal life and the environment. In this study, nanocomposite films containing 2.5 wt% sodium caseinate and 2 wt% glycerol were reinforced with 0.1 or 0.2 wt% nano TiO₂ prepared in two forms: spheres (P25) and tubes. The effects of nanoreinforcement geometry on mechanical, tensile, barrier, thermogravimetric, and optical properties, and distribution of nanoparticles were described. The interactions among film components were analyzed by Fourier transform infrared spectroscopy (FTIR). Addition of nanotubes significantly increased E' (341 wt%) and E" (395 wt%) moduli, the Young modulus E (660 wt%), the residual mass at 500°C (38 wt%), and color change (6.78) compared to control film. The compositional mapping studies showed that P25 nanoparticles were homogeneously distributed between the surfaces of the film while nanotubes were found on the bottom surface. The changes in position of the FTIR spectra signals as compared to pure protein signals indicated strong matrix/reinforcement interactions. In addition, the changes in intensity in 1100, 1033, and 1638 cm^-1 FTIR signals suggested formation of a protein/Tween 20 ester. The geometry of reinforcement was highly relevant regarding physical properties, showing nanotubes as being very successful for enhancing tensile properties.

Microwave-Treated Physically Cross-Linked Sodium Alginate and Sodium Carboxymethyl Cellulose Blend Polymer Film for Open Incision Wound Healing in Diabetic Animals-A Novel Perspective for Skin Tissue Regeneration Application

This study aimed at developing the microwave-treated, physically cross-linked polymer blend film, optimizing the microwave treatment time, and testing for physicochemical attributes and wound healing potential in diabetic animals. Microwave-treated and untreated films were prepared by the solution casting method and characterized for various attributes required by a wound healing platform. The optimized formulation was tested for skin regeneration potential in the diabetes-induced open-incision animal model. The results indicated that the optimized polymer film formulation (MB-3) has significantly enhanced physicochemical properties such as high moisture adsorption (154.6 ± 4.23%), decreased the water vapor transmission rate (WVTR) value of (53.0 ± 2.8 g/m²/h) and water vapor permeability (WVP) value (1.74 ± 0.08 g mm/h/m²), delayed erosion (18.69 ± 4.74%), high water uptake, smooth and homogenous surface morphology, higher tensile strength (56.84 ± 1.19 MPa), and increased glass transition temperature and enthalpy (through polymer hydrophilic functional groups depicting efficient cross-linking). The in vivo data on day 16 of post-wounding indicated that the wound healing occurred faster with significantly increased percent re-epithelialization and enhanced collagen deposition with optimized MB-3 film application compared with the untreated group. The study concluded that the microwave-treated polymer blend films have sufficiently enhanced physical properties, making them an effective candidate for ameliorating the diabetic wound healing process and hastening skin tissue regeneration.

Effect of Non-Thermal Food Processing Techniques on Selected Packaging Materials

In the last decade both scientific and industrial community focuses on food with the highest nutritional and organoleptic quality, together with appropriate safety. Accordingly, strong efforts have been made in finding appropriate emerging technologies for food processing and packaging. Parallel to this, an enormous effort is also made to decrease the negative impact of synthetic polymers not only on food products (migration issues) but on the entire environment (pollution). The science of packaging is also subjected to changes, resulting in development of novel biomaterials, biodegradable or not, with active, smart, edible and intelligent properties. Combining non-thermal processing with new materials opens completely new interdisciplinary area of interest for both food and material scientists. The aim of this review article is to give an insight in the latest research data about synergies between non-thermal processing technologies and selected packaging materials/concepts.

Ultrasonication effects on physicochemical properties of biopolymer-based films: A comprehensive review

Biopolymeric films manufactured from materials such as starch, cellulose, protein, chitosan, gelatin, and polyvinyl alcohol are widely applied due to their complete biodegradability. While biopolymer-based films exhibit good gas barriers and optical properties when used in packaging, poor moisture resistance and mechanical properties limit their further application. Ultrasonication is a promising, effective technology for resolving these shortcomings, with its high efficiency, environmentally friendly nature, and safety. This review briefly introduces basic ultrasonication principles and their main effects on mechanical properties, transparency, color, microstructure, water vapor permeability, and oxygen resistance. We also describe the thermal performance of biopolymeric films. While ultrasonication has many positive effects on the physicochemical properties of biopolymeric films, many factors influence their behavior during film preparation, including power density, amplitude, treatment time, frequency, and the inherent properties of the source materials. This review focuses on biopolymers as film-forming materials and comprehensively discusses the promotional effects of ultrasonication on their physicochemical properties.

High-performance soy protein-based films from cellulose nanofibers and graphene oxide constructed synergistically via hydrogen and chemical bonding

Soybean protein isolate (SPI) shows a broad application prospect in the food and packaging industry. However, its inferior mechanical properties and water resistance limit its application. In this work, a series of SPI-based composite films were prepared by combining with cellulose nanofiber (CNF), graphene oxide (GO), GO/CNF, ethylene glycol diglycidyl ether (EDGE) or GO/CNF/EGDE. The results show that by adding a small amount of reinforced materials (3%), the water resistance, hydrophilicity, mechanical properties and thermal stability of composite films were improved. The filling effect and hydrogen bonding of the reinforcing materials contribute to the formation of film structure. EGDE cross-link SPI with CNF and GO build a chemical network to improve the properties of the film. In addition, they could make a synergistic effect to better enhance the performance of a protein film. Therefore, the tensile strength and elastic modulus of the SGCE film reached 469.21% and 367.58%, respectively.

Soybean protein isolate (SPI) shows a broad application prospect in the food and packaging industry.

Protein–TiO2: A Functional Hybrid Composite with Diversified Applications

Functionalization of protein-based materials by incorporation of organic and inorganic compounds has emerged as an active research area due to their improved properties and diversified applications. The present review provides an overview of the functionalization of protein-based materials by incorporating TiO2 nanoparticles. Their effects on technological (mechanical, thermal, adsorptive, gas-barrier, and water-related) and functional (antimicrobial, photodegradation, ultraviolet (UV)-protective, wound-healing, and biocompatibility) properties are also discussed. In general, protein–TiO2 hybrid materials are biodegradable and exhibit improved tensile strength, elasticity, thermal stability, oxygen and water resistance in a TiO2 concentration-dependent response. Nonetheless, they showed enhanced antimicrobial and UV-protective effects with good biocompatibility on different cell lines. The main applications of protein–TiO2 are focused on the development of eco-friendly and active packaging materials, biomedical (tissue engineering, bone regeneration, biosensors, implantable human motion devices, and wound-healing membranes), food preservation (meat, fruits, and fish oil), pharmaceutical (empty capsule shell), environmental remediation (removal and degradation of diverse water pollutants), anti-corrosion, and textiles. According to the evidence, protein–TiO2 hybrid composites exhibited potential applications; however, standardized protocols for their preparation are needed for industrial-scale implementation.

Development of starch based intelligent films by incorporating anthocyanins of butterfly pea flower and TiO2 and their applicability as freshness sensors for prawns during storage

Intelligent pH sensitive starch films were developed by incorporation of anthocyanin pigment extracted from butterfly pea flower (BPE) and nanosized TiO2 using the method of solution casting. This research work evaluated the influence of BPE and TiO2 on the physical and structural properties of starch films. The physical properties of the starch films could be significantly altered by the addition of BPE and or TiO2. The starch films S/BPE and S/BPE/TiO2 exhibited higher barrier properties against water vapour as compared to the control films. Incorporation of BPE and TiO2 could decrease the thickness and moisture content of films. S, S/BPE starch films were transparent and, S/TiO2 and S/BPE/TiO2 films were opaque. Control starch films were colourless, whereas S/BPE films have purple colour. Owing to the inclusion of BPE and TiO2 particles, structural characterization by X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) did not show any major changes in polymer structure. Thermogravimetric analysis revealed that the addition of TiO2 enhanced the thermal stability of starch films to a significant extent. The color of different starch-based films was determined using the CIE Lab scale under different pH conditions and compared with the control. The fabricated (S/BPE and S/BPE/TiO2) films exhibited visually perceptible colour changes in the pH range between 1 and 12. Consequently these films could be used as intelligent pH indicators for monitoring the freshness of prawn seafood samples. During the storage of prawn food samples for 6 days, the color of the film changed from light pink to green which is a clear indication of spoilage of food material.

The Effects of Novel Thermal and Nonthermal Technologies on the Properties of Edible Food Packaging

Edible packaging is influenced by factors such as formulation, production technology, and solvent and additive properties. With the increase in the request for coating and film quality, appropriate form, and high product safety and storage period, various technologies such as high hydrostatic pressure, irradiation, ultrasound, high-pressure homogenization, cold plasma, and microwave have been reviewed. The present study states definitions and mechanisms of novel technologies. The experimental condition, packaging matrix, and the results pertaining to the effects of these technologies on various types of edible packaging is also discussed. The most of the matrix used for packaging was whey protein, soy protein isolate, chitosan, and gelatin. The technologies conditions such as power, frequency, time, temperature, dose, pressure, and voltage can have a significant influence on the application of them in film and coating. Therefore, finding the optimum point for the features of the technologies is important because improper use of them reduces the properties of the edible packaging.

Preparation and Characterization of Soy Protein Isolate Films Incorporating Modified Nano-TiO2

Antimicrobial films were prepared by incorporating nano-titanium dioxide (TiO2) modified by silane into soy protein isolate (SPI) films. The effects of different concentrations of modified nano-TiO2 (TiO2-NM) on the physical properties, antimicrobial properties, and microstructure of the SPI-based films were investigated. Attenuated total reflectance Fourier-transform infrared spectroscopy indicated that the interaction between the SPI and TiO2-NM was via hydrogen bonds. Scanning electron microscopy and atomic force microscopy both showed that the microstructure of SPI-based films with TiO2-NM was compact. Moreover, as the content of TiO2-NM increased from 0 to 1.5 g/100 mL, the water vapor permeability and oxygen permeability were decreased from 5.43 to 4.62 g· mm/m2d· kPa and 0.470 to 0.110 g· cm−2· d−1, respectively. An increase from 6.67 MPa to 14.56 MPa in tensile strength and a decrease from 36.53% to 27.62% in elongation at break indicate the optimal mechanical properties of all groups. TiO2-NM films had excellent UV barrier properties, with a whiter surface with increasing TiO2-NM content. In addition, the SPI-based films with TiO2-NM showed antimicrobial activity, as evidenced by an inhibitory zone increasing from 0 to 27.34 mm. Therefore, TiO2-NM can be used as an antimicrobial agent in packaging films.

Mechanical and moisture barrier properties of corn distarch phosphate film influenced by modified microcry stalline corn straw cellulose

BACKGROUND

In this paper, a novel modified microcrystalline corn straw cellulose (MMCSC) was prepared by ultrasonic/microwave-assisted treatment. Effective incorporation of MMCSC into corn distarch phosphate (CDP)-based composite films was investigated.

RESULTS

As the proportion of MMCSC was increased, tensile strength increased initially before decreasing, and the elongation at break always decreased. The composite film of MMCSC20 showed the lowest water vapor permeability (2.917 × 10^-7 g m^-1 h^-1 Pa^-1 ). The measurement of surface color showed that by the increasing of the MMCSC proportion in composite films, the L^* and b^* values and the total color difference (ΔE^* ) increased, while a^* values decreased. Fourier transform infrared spectroscopy and X-ray diffraction analysis indicated that, with the incorporation of MMCSC, the stable structure of the films was enhanced through cross-linking and the crystallinity was increased. A scanning electron microscopy study revealed the surface microstructure of films (MMCSC0-MMCSC30) was smooth and homogeneous, and there was no distinct separation in the matrix of composite films.

CONCLUSION

The incorporation of suitable MMCSC could improve the properties of composite films. The CDP-MMCSC films, which are completely biodegradable and environmental friendly, have a high potential to be used for food packaging. © 2018 Society of Chemical Industry.

Fabrication, properties and applications of soy-protein-based materials: A review

The environmental crisis caused by the use of petroleum-based nondegradable polymers and the impending petroleum finite resources have directly threatened human being's sustainable development. Therefore, ecofriendly polymers based on natural renewable resources are attracting more and more attention. As the byproducts of soy oil industries, soy protein, is regarded as a viable alternative for petroleum-based polymeric products. In order to improve the physical properties, especially the mechanical properties and water resistance that limit their extensive applications, different modifications were adopted. Among these efforts, incorporating nanoparticles and blending with other polymers are proved to be effective ways. The properties of the resulting materials are highly dependent on the processing methods, nature of the components, dispersion status and the compatibility. This review intends to provide a clear overview on preparation, properties, and applications of soy-protein-based materials. These biodegradable materials will find more and more potential applications in biodegradable foams, edible films, packaging materials, biomedical materials, etc.

Effects of ultrasonic/microwave-assisted treatment on the properties of corn distarch phosphate/corn straw cellulose films and structure characterization

Edible films were casted using aqueous solutions of corn distarch phosphate (CDP, 3 wt%) and corn straw cellulose (CSC, 0.5 wt%). The effects of ultrasonic, microwave and ultrasonic/microwave-assisted treatment on mechanical properties and light transmittance, as well as the water vapour permeability (WVP) of edible films, were evaluated. It was found that corn distarch phosphate/corn straw cellulose (CDP/CSC) films treated using ultrasonic waves/microwaves for a certain condition has a distinct increase in tensile strength, elongation at break and light transmittance and a drastic decrease in WVP. Moreover, scanning electron microscopy demonstrated that the surface and cross-section morphology of CDP/CSC films after ultrasonic/microwave-assisted treatment were smoother, denser and without a notable phase separation compared with control films. The results of mechanical properties and barrier properties were in agreement with the changes in molecular interactions detected by Fourier transform infrared spectroscopy and X-ray diffraction analysis. These findings indicate that ultrasonic/microwave-assisted treatment can improve the application of biodegradable films.

Transesterification of soybean oil by using the synergistic microwave-ultrasonic irradiation

Microwave and ultrasound have been demonstrated to be outstanding process intensification techniques for transesterification of oil. According to their mechanisms, simultaneous effects can surely bring about better enhancement than sole microwave or ultrasound. Therefore, this study aimed to investigate the important factors and their suitable levels in the KOH-catalyzed transesterification of soybean oil with methanol by using synergistic assistance of microwave-ultrasound (CAMU). The feasibility of application of CAMU in transesterification of oil was demonstrated. When the dosage of methanol, soybean oil and KOH were 15.4g, 34.7g (with methanol-to-oil molar ratio of 12:1) and 1g, respectively, and the microwave power, ultrasonic power, ultrasonic mode, reaction temperature and reaction time were 700W, 800W, 1:0, 65°C and 6min, respectively, the transesterification reached 98.0% of yield, being the highest yield among all the results obtained; while by using 600W of microwave plus stirring instead of CAMU, only 57.4% of yield could be obtained. Compared with other reaction techniques, the transesterification by applying novel CAMU was found to have remarkable advantages. Furthermore, by monitoring the variation of real-time temperature and microwave power during transesterification reactions with different microwave operation time and by taking comparison of the corresponding yield, it was demonstrated that the main reason for the acceleration of microwave-assisted transesterification was the polarization and further activation of reactants caused by microwave irradiation, but not the factor of fast heating.