scholarly journals Investigation of Ultrasonic Treatment on Physicochemical, Structural and Morphological Properties of Sodium Alginate/AgNPs/Apple Polyphenol Films and Its Preservation Effect on Strawberry

Polymers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2096
Author(s):  
Wenting Lan ◽  
Siying Li ◽  
Shiti Shama ◽  
Yuqing Zhao ◽  
Dur E. Sameen ◽  
...  

An antibacterial and anti-oxidation composite film was prepared by a casting method using sodium alginate (SA) and apple polyphenols (APPs) as the base material and glycerol as the plasticizer. Silver nanoparticles (AgNPs) were deposited by ultrasonic-assisted electrospray method. The degree of influence of the addition ratio of SA and AgNPs and different ultrasonic time on the mechanical properties, barrier properties, optical properties, and hydrophilicity of the composite film was explored. The composite films were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that the SA: AgNPs ratio of 7:3 and the ultrasonic time for 30 min have the best comprehensive performance, and SA/AgNPs/APP films showed the lowest water vapor permeability value of 0.75 × 10−11 g/m·s·Pa. The composite film has good strength and softness, with tensile strength (TS) and elongation at break (E) at 23.94 MPa and 29.18%, respectively. SEM images showed that the surface of the composite film was smooth and the AgNPs’ distribution was uniform. The composite film showed broad antibacterial activity, and the antibacterial activity of Escherichia coli (92.01%) was higher than that of Staphylococcus aureus (91.26%). However, due to the addition of APP, its antioxidant activity can reach 98.39%, which has a synergistic effect on antibacterial activity. For strawberry as a model, the results showed that this composite film can prolong the shelf life of strawberries for about 8 days at 4 °C, effectively maintaining their storage quality. Compared with the commonly used PE(Polyethylene film) film on the market, it has a greater fresh-keeping effect and can be used as an active food packaging material.

2020 ◽  
pp. 089270572096215 ◽  
Author(s):  
Sajed Amjadi ◽  
Saghar Nouri ◽  
Roghieh Ashrafi Yorghanlou ◽  
Leila Roufegarinejad

The present study aimed to fabrication and characterization the hydroxypropyl methylcellulose (HPMC) films containing different concentrations of sodium alginate (0.5, 1, and 3% v/v) and Dracocephalum moldavica L. essential oil (DEO; 1, 3 and 5% v/v) as a biodegradable active packaging system. FTIR analysis confirmed the interaction of alginate groups with the hydroxyl group of HPMC. SEM images indicated that the addition of alginate decreased the size and number of the cracks. As a result, the incorporation of alginate and DEO significantly (p < 0.05) improved the water barrier properties of films and the lowest values of water vapor permeability (.38 × 10−10 g/m·h·Pa), moisture content (6.30 ± 0.08%) and water solubility (29.49 ± 0.04%) were related to the sample containing 1.5% alginate and 5% DEO. Additionally, blending with alginate significantly (p < 0.05) improved the mechanical properties of the films and the blended film sample with 0.5% alginate showed the highest tensile strength (16.13 MPa). The blend films showed high thickness and whiteness Index. Also, the antioxidant activity of the films was enhanced by incorporation DEO and the highest DPPH scavenging activity (74.58 ± 2.31%) was attributed to the samples incorporated with 5% DEO. In conclusion, the fabricated blend film showed considerable potential for active food packaging.


Membranes ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 18
Author(s):  
Guanghui Shen ◽  
Guoxian Yu ◽  
Hejun Wu ◽  
Shanshan Li ◽  
Xiaoyan Hou ◽  
...  

This work evaluated the improvement effects of lipids incorporation on water resistance of composite biodegradable film prepared with wheat bran cellulose/wheat gluten (WBC/WG) using an alkaline–ethanol film forming system. Four types of lipids, paraffin wax (PW), beeswax (BW), paraffin oil (PO), and oleic acid (OA), were tested. We found that PW, BW, and PO incorporation at 5–20% improved water vapor permeability (WVP) and surface hydrophobicity of prepared films. Particularly, incorporation of 15% BW could best improve the water resistance properties of the film, with the lowest WVP of 0.76 × 10−12 g/cm·s·Pa and largest water contact angle (WCA) of 86.18°. Incorporation of OA led to the decline in moisture barrier properties. SEM images revealed that different lipids incorporation changed the morphology and of the composite film, and cross-sectional morphology indicated BW-incorporated film obtained more uniform and compact structures compared to other films. Moreover, Fourier transform infrared spectra indicated that the incorporation of PW or BW enhanced the molecular interactions between the film components, confirmed by the chemical shift of characteristic peaks at 3277 and 1026 cm−1. Differential scanning calorimetry results revealed that incorporation of PW, BW, and PO increased films’ melting point, decomposition temperatures, and enthalpy values. Furthermore, the presence of most lipids decreased tensile strength and elongation at the break of the film. Overall, the composite film containing 15% BW obtained the most promising water resistance performance and acceptable mechanical properties, and it thus most suitable as a hydrophobic biodegradable material for food packaging.


Nanomaterials ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 930 ◽  
Author(s):  
Siying Tang ◽  
Zhe Wang ◽  
Penghui Li ◽  
Wan Li ◽  
Chengyong Li ◽  
...  

A degradable and antibacterial sodium alginate film containing functional Au-TiO2 nanocomposites for food packaging was successfully developed. The Au-TiO2 nanocomposites are synthesized hydrothermally and mixed with the alginate solution to form the film by a casting method. The Au-TiO2 nanocomposites enable the film with excellent visible light absorption and transfer ability with the light absorption rang covering UV–visible wavelength (300–800 nm) and induce the increase of the film water contact angle from 40° to 74°, which contributes to the film shape stability. Furthermore, compared to the TiO2 nanoparticle-incorporated film, the antibacterial ability of Au-TiO2/sodium alginate composite film is improved approximately by 60% and 50% against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), respectively, in light conditions. The antibacterial property of the film arises from the increased production of reactive oxygen species (ROS) induced by the surface plasmonic resonance of Au nanoparticles. The degradable and antibacterial properties render the composite film of great application potential in food packaging industry.


2013 ◽  
Vol 706-708 ◽  
pp. 197-200 ◽  
Author(s):  
Zhi Hong Zhang ◽  
Yu Yue Qin ◽  
Jian Fan ◽  
Tian Rui Zhao ◽  
Chun Sheng Cheng

Chitosan-based films containing lavender essential oil (LEO) (0, 0.5%, 1.0%, 1.5% (v/v)) were prepared to evaluate their physical and antibacterial activities. In order to study the impact of the incorporation of LEO into chitosan matrix, the solubility, mechanical property, water vapor permeability, and antibacterial activity of the films were investigated. Fourier transform infrared chromatography (FTIR) was carried out to explain structure–property relationships. Results showed that the solubility and water vapor permeability of the chitosan-based film decreased by LEO incorporation. Films containing LEO showed better mechanical property. FTIR spectra demonstrated good interaction between functional groups of chitosan with LEO. With the concentration of LEO increased from 0 to 1.5 %, the inhibitory zone of four bacterial strains (Escherichia coli, Staphylococcus aurous, Bacillus magaterium, Bacillus subtilis) increased. It can be concluded that chitosan films containing LEO can be used for development of active food packaging materials.


Polymers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 200
Author(s):  
Celeste Cottet ◽  
Andrés G. Salvay ◽  
Mercedes A. Peltzer ◽  
Marta Fernández-García

Poly(itaconic acid) (PIA) was synthesized via conventional radical polymerization. Then, functionalization of PIA was carried out by an esterification reaction with the heterocyclic groups of 1,3-thiazole and posterior quaternization by N-alkylation reaction with iodomethane. The modifications were confirmed by Fourier transform infrared (FTIR) and proton nuclear magnetic resonance (1H-NMR), as well as ζ-potential measurements. Their antimicrobial activity was tested against different Gram-negative and Gram-positive bacteria. After characterization, the resulting polymers were incorporated into gelatin with oxidized starch and glycerol as film adjuvants, and dopamine as crosslinking agent, to develop antimicrobial-active films. The addition of quaternized polymers not only improved the mechanical properties of gelatin formulations, but also decreased the solution absorption capacity during the swelling process. However, the incorporation of synthesized polymers increased the deformation at break values and the water vapor permeability of films. The antioxidant capacity of films was confirmed by radical scavenging ability and, additionally, those films exhibited antimicrobial activity. Therefore, these films can be considered as good candidates for active packaging, ensuring a constant concentration of the active compound on the surface of the food, increasing products’ shelf-life and reducing the environmental impact generated by plastics of petrochemical origin.


Coatings ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 280
Author(s):  
Rui Lu ◽  
Dur E. Sameen ◽  
Wen Qin ◽  
Dingtao Wu ◽  
Jianwu Dai ◽  
...  

Selenium is a natural element which exists in the human body and plays an important role in metabolism. Along with this, selenium also possesses antibacterial and antioxidant properties. Using selenium microparticles (SeMPs) in food packaging films is exceptional. In this experiment, a solution casting method was used to make film. For this purpose, we used polylactic acid (PLA) as a substrate for the formation of a film membrane while SeMPs were added with certain ratios to attain antibacterial and antioxidant properties. The effects of SeMPs on the PLA film and the value of SeMPs in food packaging film production were investigated. The effects of the SeMPs contents on the features of the film, such as its mechanical property, solubility, swelling capacity, water vapor permeability, antioxidant activity, and the antibacterial activity of the composite membrane against Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative) strains, were studied. The results manifest that the PLA/SeMPs films showed higher water resistance, UV resistance, antioxidant activity, and antibacterial activity than pure PLA film. When the concentration of SeMPs was 1.5 wt%, the composite membrane showed the best comprehensive performance. Although the tensile strength and elongation at break of the membrane were slightly reduced by the addition of SeMPs, the results show that PLA/SeMPs films are still suitable for food packaging and would be a very promising material for food packaging.


Foods ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 1117
Author(s):  
Shubham Sharma ◽  
Sandra Barkauskaite ◽  
Brendan Duffy ◽  
Amit K. Jaiswal ◽  
Swarna Jaiswal

Bioactive packaging contains natural antimicrobial agents, which inhibit the growth of microorganisms and increase the food shelf life. Solvent casting method was used to prepare the Poly (lactide)-Poly (butylene adipate-co-terephthalate) (PLA-PBAT) film incorporated with the thyme oil and clove oil in various concentrations (1 wt%, 5 wt% and 10 wt%). The clove oil composite films depicted less green and more yellow as compared to thyme oil composite films. Clove oil composite film has shown an 80% increase in the UV blocking efficiency. The tensile strength (TS) of thyme oil and clove oil composite film decreases from 1.35 MPs (control film) to 0.96 MPa and 0.79, respectively. A complete killing of S. aureus that is a reduction from 6.5 log CFU/mL to 0 log CFU/mL was observed on the 10 wt% clove oil incorporated composite film. Clove oil and thyme oil composite film had inhibited E. coli biofilm by 93.43% and 82.30%, respectively. Clove oil composite film had exhibited UV blocking properties, strong antimicrobial activity and has high potential to be used as an active food packaging.


2014 ◽  
Vol 884-885 ◽  
pp. 481-484 ◽  
Author(s):  
Yan Wu ◽  
Ming Wei Yuan ◽  
Ji Yi Yang ◽  
Yu Yue Qin ◽  
Ming Long Yuan ◽  
...  

Thymol (TH), which has antimicrobial effect on many food pathogens, was incorporated as antimicrobial agent into composite poly (lactic acid)/poly (trimethylene carbonate)(PLA-PTMC) films. Antimicrobial active films based on PLA-PTMC were prepared by incorporating thymol at five different concentrations: 0, 3, 6, 9 and 12 %(w/w). The mechanical characterization, water vapor permeability (WVP), and antimicrobial activity of all formulations composite film were carried out. A decrease in elastic modulus was obtained for the active composite film compared with neat PLA-PTMC film. The presence of thymol decreased water vapor permeability, with a significant antimicrobial activity. Antimicrobial activities of films were tested against Escherichia coli, Staphylococcus aurous, Listeria, Bacillus subtilis, and Salmonella. Increasing amount of the thymol in the film caused a significant increase in inhibitory zones. These results suggest that thymol incorporated PLA-PTMC films have a prospectively potential in antimicrobial food packaging.


2017 ◽  
Vol 42 ◽  
pp. 101-108 ◽  
Author(s):  
Lidan Zhang ◽  
Hualin Wang ◽  
Chongyang Jin ◽  
Ru Zhang ◽  
Linlin Li ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document