Light Barrier Research Articles

The Factors Influencing Wildlife to Use Existing Bridges and Culverts in Giant Panda National Park

Roads, acting as barriers, hamper wildlife movements and disrupt habitat connectivity. Bridges and culverts are common structures on roads, and some of them can function to allow wildlife passage. This study investigated the effects of traffic, the surrounding landscape, human disturbance, and bridge and culvert structures on the utilization of bridges and culverts as dedicated passages by wildlife, using motion-activated infrared camera traps along a 64 km road in Giant Panda National Park, Sichuan, China. The results show that both species richness and counts of wildlife recorded at the bridge and culvert were significantly lower than those observed at sites distant from roads. No large-sized wildlife was recorded at the bridges and culverts. Human activities and traffic volume significantly and negatively affect medium-sized wildlife utilization of bridges and culverts. We conclude that bridges and culverts serve as wildlife crossings, but their efficacy is weak. This emphasizes the necessity of retrofitting bridges and culverts via mitigation facilities such as noise and light barriers, and vegetation restoration on both sides of the roads in Giant Panda National Park.

Pectin from plantain peels: Green recovery for transformation into reinforced packaging films

Plantain peels as agro-waste are generated in the millions of tons per year with no profitable management strategies. On the other hand, the excessive use of plastic packaging threatens the environment and human health. This research aimed to address both problems via a green approach. High-quality pectin was recovered from plantain peels via an enzyme-assisted and ethanol-recycling process. The yield and galacturonic acid (GalA) content of the recovered low methoxy pectin was 12.43% and 25.0%, respectively, when cellulase was added at 50 U per 5 g peel powder, with a significantly higher recovery rate and purity than the pectin products extracted with no cellulase (P ≤ 0.05). The recovered pectin was further integrated and reinforced with beeswax solid-lipid nanoparticles (BSLNs) to fabricate films as a potential alternative packaging material to single-use plastics. The reinforced pectin films showed improved light barrier, water resistance, mechanical, conformational, and morphological properties. This study presents a sustainable strategy to transform plantain peels into pectin products and pectin-based packaging films with broad applications.

SAVES US: Suppression of Airborne Viral Epidemic Spread by Ultraviolet light barriers

SAVES US: Suppression of Airborne Viral Epidemic Spread by Ultraviolet light barriers

Waste Orange Peels as a Source of Cellulose Nanocrystals and Their Use for the Development of Nanocomposite Films.

To date, approximately 30-50% of food is wasted from post-harvesting to consumer usage. Typical examples of food by-products are fruit peels and pomace, seeds, and others. A large part of these matrices is still discarded in landfills, while a small portion is valorized for bioprocessing. In this context, a feasible strategy to valorize food by-products consists of their use for the production of bioactive compounds and nanofillers, which can be further used to functionalize biobased packaging materials. The focus of this research was to create an efficient methodology for the extraction of cellulose from leftover orange peel after juice processing and for its conversion into cellulose nanocrystals (CNCs) for use in bionanocomposite films for packaging materials. Orange CNCs were characterized by TEM and XRD analyses and added as reinforcing agents into chitosan/hydroxypropyl methylcellulose (CS/HPMC) films enriched with lauroyl arginate ethyl (LAE®). It was evaluated how CNCs and LAE® affected the technical and functional characteristics of CS/HPMC films. CNCs revealed needle-like shapes with an aspect ratio of 12.5, and average length and width of 500 nm and 40 nm, respectively. Scanning electron microscopy and infrared spectroscopy confirmed the high compatibility of the CS/HPMC blend with CNCs and LAE®. The inclusion of CNCs increased the films' tensile strength, light barrier, and water vapor barrier properties while reducing their water solubility. The addition of LAE® improved the films' flexibility and gave them biocidal efficacy against the main bacterial pathogens that cause foodborne illness, such as Escherichia coli, Pseudomonas fluorescens, Listeria monocytogenes, and Salmonella enterica.

Antioxidant and ammonia-sensitive films based on starch, κ-carrageenan and Oxalis triangularis extract as visual indicator of beef meat spoilage

In this study, we first investigated the rheological property of sweet potato starch (SPS), κ-carrageenan (KC) and Oxalis triangularis extract (OTE) blends and found that the blends exhibited high apparent viscosity with an apparent shear thinning behavior. And then films based on SPS, KC and OTE were developed and their structural and functional properties were studied. The physico-chemical test results showed that OTE exhibited different colors in solutions with different pH values and the incorporation with OTE and KC could significantly increase the thickness, water vapor permeability, light barrier ability, tensile strength and elongation at break as well as the pH- and ammonia-sensitive properties of the SPS film. The structural property test results showed that some intermolecular interactions between OTE and SPS/KC occurred in SPS-KC-OTE films. Finally, the functional properties of SPS-KC-OTE films were examined and SPS-KC-OTE films showed significant DPPH radical scavenging activity as well as a visible color change in response to changes in beef meat freshness. Our results suggested that the SPS-KC-OTE films could be used as an active and intelligent food packaging material in food industry.

Development of active packaging films based on collagen/gallic acid-grafted chitosan incorporating with ε-polylysine for pork preservation

Active packaging films (CCG/PL) based on collagen, functionalized chitosan with gallic acid (GA), and ε-polylysine (ε-PL) (different amount of 2.5, 5, and 10 wt%, respectively) were developed to prolong the shelf life of pork stored at 4 °C. Fourier transform infrared analysis indicated that hydrogen bonds had formed between collagen molecules and GA moieties, and there were no strong interactions between polymers and ε-PL. SEM images showed that the cross-sections of CCG/PL films were compact but aggregation of ε-PL occurred when ε-PL content reached 10 wt%. CCG/PL films possessed strong light barrier properties with the UV light transmittance lower than 4% in the range of 200–350 nm. Compared with CC film, the DPPH free radical scavenging rate was significantly increased by 84.35% due to the synergistic effect of GA and ε-PL on antioxidant activity. CCG/PL film containing 5 wt% ε-PL had excellent antimicrobial activity against S. aureus as well as good tensile strength (65.34 MPa). The wrapping of CCG/PL film with 5 wt% ε-PL effectively retarded the lipid oxidation of pork and inhibited the growth of bacterium during the storage time, and the shelf life of pork was prolonged by approximately 5 days than that of pork in polyethylene film.

An Electromagnetic-Driven Microshutter Array in a Field-of-View Gated Image System for All-Time Star Sensors

Aiming at the application requirements of a field of view (FOV) gated imaging system for all-time star sensors, a key device of a microshutter array with large unit size, high duty cycle, and fast response speed based on the electromagnetic actuation is designed. The proposed microshutter array adopts the principle that the current-carrying coil is subjected to the magnetic force in the magnetic field. The coil element is deflected by the loading current and acts as a light barrier in realizing the optical switch function. The effects of the coil element parameters on the magnetic force torque, torsion beam resistance torque, and switch response time are analyzed, and the structural parameters of the coil element are determined. A sample of the proposed microshutter array based on the electromagnetic actuation with a 4-mm period and a 2.8-mm aperture is fabricated and tested. The test results demonstrate the good switching function of the proposed microshutter array and show that the switch response time of the microshutter element is approximately 2.5 ms. This proposed microshutter array is used to gate an instantaneous small FOV to suppress the sky's background radiation and make a FOV-gated imaging system realize the multi-stars detection by switching the gated FOV rapidly. This will solve the problem that only one star can be detected within the FOV by a traditional all-time star tracker and promote the all-time star sensor to realize star pattern recognition and autonomous astronomical navigation in the daytime.

Counting in the dark: estimating population size and trends of bat assemblages at hibernacula using infrared light barriers

AbstractAccurate population estimates are crucial to developing successful conservation policy, but the underlying data remain difficult to collect for many taxa. This is especially true for elusive species, such as temperate‐zone bats, where visual counts in hibernacula underestimate their population to an unknown extent. Infrared light barriers that count all entering and exiting bats at the entrance of a hibernaculum could offer a more accurate alternative for bat population monitoring. We used infrared video recordings to quantify light barrier accuracy (i.e., concordance between light barrier and video registration of entries and exits) at five hibernacula over 30 weeks during autumn and spring. Subsequently, we developed a standardized methodology to estimate light barrier‐based population sizes based on the number of emerging bats in spring, and compared these estimates to visual counts at 12 sites. Finally, we calculated confidence intervals around the estimated population sizes, and used these to evaluate population trends using 6‐year‐long light barrier datasets from four sites. Light barrier accuracy varied based on the model and precise location of the installation, with the best combination achieving near‐perfect accuracy across the entire emergence phase. When compared to the resulting light barrier‐based population estimates, winter hibernation counts markedly underestimated population totals, recovering less than 10% of the bats at the most complex sites. Moreover, light barrier‐based population trends showed regional patterns of growth and decline, which were not evident in the visual counts. This study demonstrates that light barriers can estimate the population size and trends of bat assemblages with unprecedented accuracy, even at large, complex, or inaccessible hibernacula that cannot be precisely assessed with visual hibernation counts. Installing light barriers at a representative network of sites, where their installation does not require large‐scale entrance modifications, has the potential to revolutionize bat monitoring and contribute to data‐driven conservation.

Innovative design of bio-functional Persian gum-based edible films by incorporating crocin and cinnamaldehyde: Free versus single and double emulsion fabrication techniques

The objective of this research was to fabricate a new generation of bio-functional Persian gum-based films via the co-delivery of crocin and cinnamaldehyde. Different loading strategies using single W/O and O/W emulsions and W 1 /O/W 2 double emulsions were used to find how the distribution of bioactives in the film suspension can modify their physicochemical and biological properties compared to those prepared with the free forms of bioactives. The incorporation of emulsion structures significantly decreased the surface tension of film-forming solutions, but their viscosity remained relatively constant. The good compatibility between Persian gum and cinnamaldehyde/crocin was confirmed by FTIR and XRD. The optical, mechanical, and microstructural attributes of the films were more affected by the incorporation of the free form of bioactives. The UV–Vis light barrier property and hydrophobicity of the film were improved after incorporating single and double emulsions. However, the greater stability of bioactives within double emulsion against different pH (2 and 7) and temperatures (25 and 75 °C) produced more superior antibacterial and antioxidant activities. Furthermore, the homogenous distribution of double emulsion in the film matrix led to more resistant and extensible films. • Persian gum-based film was fortified with co-delivery of crocin and cinnamaldehyde. • Comparison was made between free and single and double emulsions loading techniques. • Mechanical and optical properties were more affected by free forms of bioactives. • Double emulsion strategy led to superior antibacterial and antioxidant activities. • Emulsion-based films were transparent but with high UV/Vis barrier properties.

Edible composite films based on chitosan/guar gum with ZnO[sbnd]NPs and roselle calyx extract for active food packaging

The present study aimed to prepare and characterize edible composite films. The edible composite films were made from a mixture of guar gum/chitosan with the loading of zinc oxide nanoparticles (ZnONPs) and roselle calyx extract (RCEx). The incorporation of RCEx and ZnONPs improved the antioxidant and mechanical properties of films. Based on yield of bioactive compounds obtained by the UAE method was used for the development of ZnONPs and the edible composite film. The Cross-section microstructure of the films showed that the films were dense and compact. Although the incorporation of RCEx decreased the transparency of the films, it enhanced the UV–Vis light barrier properties. The tensile strength, elongation at break, and solubility of CS/GG film, CS/GG/RCEx and, CS/GG/RCEx/ZnONPs film was found to be (35.74 MPa, 54.24 MPa and, 69.42 MPa), (15.56%, 12.27% and, 9.69%), and (67.23%, 59.41%, and 61.35%) respectively. Water vapor permeability (WVP) of the films was decreased from 4.68 to 4.06 (g /m2.day.kPa) after the addition of zinc oxide nanoparticles into the films, respectively. RCEx and ZnONPs incorporated films showed the higher antioxidant activity than control film, 11.52%, 42.55% and, 68.15% respectively. This study showed edible composite films incorporated ZnONPs and RCEx have promising potential for applications in active food packaging in the future.

A double-layer smart film based on gellan gum/modified anthocyanin and sodium carboxymethyl cellulose/starch/Nisin for application in chicken breast

In order to overcome this challenge of poor stability of natural anthocyanins in intelligent packaging materials, roselle anthocyanin (RA) was first modified by acetic acid, and then a double-layer smart indication antimicrobial film was developed using modified roselle anthocyanin (MRA)-gellan gum (GG) as the inner layer and sodium carboxymethyl cellulose (CMC)-starch (ST)-Nisin as the outer layer. UV spectra revealed that acetic acid was successfully grafted onto RA, which dramatically improved their thermal stability, antioxidant capabilities, photostability, and pH stability. The bilayer films were successfully prepared, as revealed by scanning electron microscopy, Fourier-transform infrared spectroscopy, and X-ray diffraction measurements. In comparison to GG-MRA and CMC-ST-Nisin films, the water content, water solubility, mechanical characteristics, water vapor barrier, oxygen barrier, and hydrophobicity of GG-MRA@CMC-ST-Nisin films were significantly enhanced. The presence of the outer layer films significantly enhanced the UV–vis light barrier, opacity, antioxidant and antibacterial properties of the inner layer films. When the films were applied to chicken breast, it was found that the indicator films not only monitored the freshness of the chicken in real-time but also that the GG-MRA film and the double-layer film were effective in extending the shelf life of the chicken by 1 and 2 days, respectively, compared to the control group.

Food packaging composite film based on chitosan, natural kaolinite clay, and Ficus. carica leaves extract for fresh-cut apple slices preservation

The problem of environmental plastic contamination is one of the most serious issues facing our world today. The majority of the packaging materials used to preserve food are made of plastic which is considered an environmental issue. Natural kaolinite clay (KC) and Ficus leaf extract (FLE) were combined with chitosan in this work to create a novel antioxidant and biodegradable food packaging film. Chitosan/KC/FLE film was compared to chitosan film, Chitosan/KC, and Chitosan/FLE films in terms of structural, physical, and functional aspects. The addition of FLE and/or KC significantly improved the light and moisture barrier characteristics, mechanical properties, and antioxidant capabilities of chitosan film. Moreover, KC addition had a remarkable impact on the water vapor permeability and the biodegradability of the chitosan film. Because of the synergistic action of FLE and KC, the Chitosan/KC/FLE film delivered strong barrier and antioxidant capabilities. Furthermore, Chitosan/KC/FLE film was tested as packaging material on fresh-cut apple slices and demonstrated good food preservation regarding the weight loss, browning index, and total phenolic content of the fruit. According to our findings, Chitosan/KC/FLE film might be employed as a possible food packaging material in the food industry.

Incorporation of oxidized debranched starch/chitosan nanoparticles for enhanced hydrophobicity of corn starch films

Starch films have superior advantages owing to the renewability and low cost of starch; however, their strong inherent hydrophilic character greatly limits their practical application. This study aimed to improve the hydrophobicity of corn starch films by adding a new type of covalently formed, oxidized debranched starch/chitosan nanoparticles (SC-NPs). SC-NPs were obtained by a Schiff-base crosslinking reaction between the aldehyde group of dialdehyde debranched starch and the amino group of chitosan. Corn starch films reinforced with SC-NPs were obtained using a casting method. A mass ratio of dialdehyde debranched starch and chitosan of 3–5 yielded mainly spherical nanoparticles ranging from 50 to 150 nm in diameter determined by transmission electron microscopy. The water contact angle (WCA) of the pure starch film was only 19.4°, whereas the WCA values of the films reinforced with 3 % SC-NPs were greater than 70°, indicating that SC-NPs efficiently improved the hydrophobicity of corn starch films. The ultraviolet and visible light barrier property of starch films with 3 % SC-NPs were significantly enhanced in comparison with pure starch film. The water vapor permeability, water solubility, and swelling ratio were markedly lower in films with 3 % SC-NPs than in neat starch films.

Effects of purple passion fruit peel extracts on characteristics of Pouteria campechiana seed starch films and the application in discernible detection of shrimp freshness

In this work, the film-forming potential of Pouteria campechiana seed starch (PCSS) and the effects of purple passion fruit (Passiflora edulis) peel extracts (PPPAEs) on the properties of films were examined for the first time. The structural analyses showed that PPPAEs had great compatibility with PCSS without altering the chemical structure of PCSS films. The addition of PPPAEs meaningfully enhanced the ultraviolet–visible light barrier properties. The mechanical properties of the PCSS films were also remarkably influenced due to the introduction of PPPAEs, as confirmed by the increased elongation at break and decreased tensile strength. Moreover, the introduction of PPPAEs endowed the PCSS films with great antioxidant properties, as well as noticeable color change when subjected to the ammonia environment and pH alternation. The PCSS/9 PPPAEs films were utilized to monitor shrimp freshness, and obvious color changes from light pinkish brown to green could be observed as shrimp freshness was reduced during storage. The PCSS-based films presented great biodegradability, as confirmed by the test result that all systems have wholly integrated into the soil and nearly disappeared after 14 days of burial. In summary, PPPAEs were capable of bestowing PCSS films with desirable properties, and the fabricated PCSS/PPPAEs composite films could potentially be used for the visible detection of the freshness of meat and aquatic products rich in proteins.

Effect of Kaolin clay and Ficus carica mediated silver nanoparticles on chitosan food packaging film for fresh apple slice preservation

In this work, a novel antioxidant, antibacterial, and biodegradable food packaging film was elaborated, by incorporating natural kaolin clay (KC) and Ficus carica mediated silver nanoparticles (AgNPs) into Chitosan (Cht). A comparison of the physico-chemical and functional characteristics of the Cht/KC/AgNPs film was performed with those of Cht, Cht/KC, and Cht/AgNPs. SEM analysis showed a rough surface in the composite films containing KC particles because of their large diameter (50–120 μm) compared to AgNPs (20–80 nm). The FTIR analysis suggested that the interactions between Cht and AgNPs were stronger than those between Cht and KC. The tensile strength of Cht film increased from 16 MPa to ∼24 MPa in Cht/KC/AgNPs film. The introduction of KC and/or AgNPs considerably improved the light and moisture barrier capacity of the Cht film. The UV light transmittance decreased by 50 % for Cht film when incorporated by KC and AgNPs. Moreover, Cht/AgNPs was better in terms of antioxidant, antibacterial, and mechanical compared to Cht/KC, which was superior in biodegradability and water vapor barrier capacity. In particular, the Cht/KC/AgNPs film presented good barrier, antioxidants, antibacterial, mechanical, and biodegradable properties, owing to the synergistic effect between KC and AgNPs. For the packaging properties, all the films were tested for their ability to keep the freshness of apple slices as wrapping material. The films exhibited good results, and the Cht/KC/AgNPs showed promising performance regarding the moisture loss, browning index, total phenolic compound, and antioxidant activity of the apple slices. Moreover, the Cht/KC/AgNPs film exhibited a migration of silver meeting the standards set by EFSA and ECHA, which makes this film safe for food packaging.

Influence mechanism of wheat bran cellulose and cellulose nanocrystals on the storage stability of soy protein isolate films: Conformation modification and molecular interaction perspective

This study aims to elucidate the changes and corresponding mechanisms of storage stability of soy protein isolate (SPI) films strengthened via wheat bran cellulose (WBC) and cellulose nanocrystals (CNC). The incorporation of WBC and CNC improved the mechanical strength, water resistance, water vapor and visible light barrier abilities of stored SPI-based films to varying degrees. Higher crystallinity and lower water mobility were observed in the composite films. WBC molecules reduced the irregular pores and cracks within the internal structure of the film through physical filling and non-covalent interactions, involving hydrogen bond and van der Waals force. In contrast, uniformly distributed CNC cross-linked with amino acid residues at specific binding sites under non-covalent forces. Furthermore, CNC induced the secondary conformation of proteins to transform from α-helix to β-sheet and enhanced the hydrophobic interaction, which promoted the establishment of a stable network structure and thus extended the storage stability of SPI-based films.

Developments of pH responsive biodegradable monitoring film based on poly(vinyl alcohol) incorporated with Sappan heartwood extract for food packaging applications

<abstract> <p>The major problem leading to substantial waste in the food industry is the spoilage of food products during transportation and storage periods. Consequently, the scope of this research focuses on the development and preparation a pH responsive monitoring films based on biodegradable materials of poly(vinyl alcohol) (PVA) and natural colorant extract from <italic>Caesalpinia sappan</italic> L. heartwood (SP). These monitoring films were prepared by a solution casting method and the film stability was improved by crosslinking with citric acid (CA). The red tone of monitoring film without CA was observed, while the crosslinked monitoring film showed a yellow color, which occurs from the structural change of brazilin (structure presenting in SP) to brazilein under acidic conditions. From the SEM and FTIR results, the monitoring film showed high compatibility between phases, improvements in light barrier properties and good WVTR performance. The tensile strength and elongation at break were slightly increased. For pH responsive properties, the monitoring films showed a high response with NH<sub>3</sub> gas detection with the change in color from a yellow tone to a red tone. These results indicated that the monitoring films have potential to be applied as food packaging for meat, fish, pork, chicken, and other foods that generate ammonium gas during spoilage. Therefore, these high stable, and non-toxic biodegradable PVA films that incorporated with SP extract and crosslinked by CA have the potential to be used for food spoilage detection in packaging.</p> </abstract>

FUNCTIONAL AND TECHNOLOGICAL PROPERTIES OF COFFEE MUCILAGE (Coffea arabica) AND ITS APPLICATION IN EDIBLE FILMS

Brazil is the largest coffee producer in the world, and together with the millions of tons produced, millions of tons of residues are also generated. The generated residues are a source of environmental contamination depending on the chosen processing route. One of the main applications of food industry waste is in the production of raw materials to produce edible films and coatings. Coffee mucilage is a pectin-rich liquid residue from the coffee sector that can be used in the production of value-added products. Given this, the objective of this work was to characterize and evaluate the potential of functional and technological properties of coffee mucilage and your applicability in the production of edible films. The filmogenic mixture was obtained by casting from 10% (w/v) lyophilized coffee mucilage and solvent (water). The films produced from the coffee mucilage presented good homogeneity, continuity (absence of ruptures or fragile regions), flexibility, ease of detachment of the support and handling, without the need to add adjuvant to its formation. In addition, they presented uniformity in thickness, high light barrier and medium water vapor barrier. Thus, it can be concluded that mucilage is a potential product to be used in the cosmetic, pharmaceutical and food industries.

Antioxidant and antimicrobial packaging films developed based on the peel powder of different citrus fruits: A comparative study

Citrus is the largest fruit crop planted worldwide. However, the global citrus fruit processing byproducts have not been fully utilized up to now. Citrus peels contain valuable biopolymers and bioactive substances, which are suitable to develop food packaging films. In this study, active packaging films were prepared by directly utilizing citrus peels in their powder form. The films produced from the peel powder of four different citrus fruits (orange, lemon, pomelo and mandarin) were compared for their structural and functional properties. Results showed the four kinds of citrus peel powder contained 16.36%–23.80% pectin, 5.68%–8.23% protein, 3.17%–7.65% lipid, 2.88%–6.27% crude fiber and 11.45–15.47 mg GAE/g polyphenols. Four kinds of citrus peel powder based films exhibited rough surface and transverse with yellow or flesh color. These films had 0.124–0.157 mm of thickness, 18.16%–25.25% of moisture content, 51.98–121.64°of water contact angel, 1.34–1.92 × 10−10 g m−1 s−1 Pa−1 of water vapor permeability, 0.36–0.69 cm3 mm m−2 day−1 atm−1 of oxygen permeability, 8.26–9.14 MPa of tensile strength and 8.05%–17.18% of elongation at break. These films also showed strong antioxidant and antimicrobial activity, which retarded corn oil oxidation. Among the films, mandarin peel powder based film was most effective in retarding oil oxidation due to the excellent light and oxygen barrier capacity and antioxidant activity of the film. Results suggested mandarin peel powder based film was suitable for the active packaging of corn oil.

Effect of Repeated Contact to Food Simulants on the Chemical and Functional Properties of Nano ZnO Composited LDPE Films for Reusable Food Packaging

The effect of repeated contact with food simulants on the properties and functionality of zinc oxide (ZnO) in nanocomposite films was investigated to examine possible safety hazards from the point of view of long-term use as food packaging. Low-density polyethylene (LDPE) embedded with 5 wt% nano-ZnO was immersed in distilled water, 50% ethanol, 4% acetic acid, and n-heptane. The cycle of immersion-rinse-dry was repeated up to 40 times for same sample under constant condition. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray absorption spectroscopy (XAS), field emission-scanning electron microscopy (FE-SEM), and UV-Vis spectroscopy analyses were performed to identify the changes in the chemical and functional properties of the nanocomposite film. Acetic acid had the greatest impact on the LDPE-ZnO nanocomposite films, while other food simulants caused little change. A new carboxylate bond was formed by the reaction of ZnO with acetic acid, as evidenced by the FTIR spectra. In addition, XRD and XAS confirmed the phase changes of nano-ZnO into zinc salts such as zinc hydroxy acetate or zinc acetate dihydrate. Furthermore, the light barrier property of the nanocomposite film drastically decreased, owing to the change in the bandgap of ZnO and film morphology.