Fresh Food Packaging Research Articles

Recent progress in properties and application of antibacterial food packaging materials based on polyvinyl alcohol

Abstract Polyvinyl alcohol (PVA) is well-known for its excellent mechanical properties and eco-friendliness in food packaging. Recently, PVA has gained significant attention in research due to its potential as antibacterial substrates. However, because of its high hydrophilicity, practical application of pure PVA film has been limited by low water resistance and rapid bacterial growth in humid conditions. Diverse effective strategies have been developed to decrease hydrophilicity and endow films with antibacterial properties. This review provides an overview of universal antibacterial agents and their functions in PVA-based packaging films. It also introduces the changes in the mechanical and physical properties of PVA-based films after adding antibacterial agents. Additionally, the release behavior of antibacterial agents in PVA-based film materials and their practical applications in the food industry is discussed in fresh food packaging. Biodegradability of PVA-based films is also mentioned, with a promising future for more effective and eco-friendly food packaging materials.

Active packaging films based on poly(butylene succinate) films reinforced with alkaline halloysite nanotubes: Production, properties, and fruit packaging applications

Alkaline treated halloysite nanotubes (aHal) were introduced into poly(butylene succinate) (PBS) matrix using melt blending and solvent casting techniques to enhance the functional properties. The films were characterized for morphological, thermal, mechanical, antibacterial, barrier, and ethylene scavenging properties for their fresh food packaging use. The films exhibited ethylene scavenging performance because of the increased lumen diameter of aHal. The highest ethylene scavenging performance was achieved at 5 wt% aHal (5-aHal) loading for both production methods. The amount of ethylene in the gas-tight container decreased by 80% and 75% in the presence of extruded and solvent-cast 5-aHal, respectively. While PBS/aHal films have mechanical properties comparable to other films recommended for food packaging, extruded films were more flexible and durable than solvent-cast films. In addition, extruded films were found to have a higher water vapor barrier. A packaging test has also been carried out on sliced tomatoes and apples stored at room conditions for 7 days. 5-aHal films showed the best performance in extending the fruit's shelf life. Considering all the results, the melt blending films offer superior performance. Bio-based PBS/aHal films have the capability to contribute significantly to the food safety by serving as eco-friendly, active food packaging materials.

Eco-Friendly packaging film with integrated functions of High-Efficiency radiation cooling and Sustained-Release antimicrobial activity

The storage temperature and microbial contamination typically have significant impact on the deterioration rate and postharvest lifespan of fresh food. To meet the critical requirements of fresh food packaging, a hybrid functional packaging coating is developed by combing tannic acid (TA) as a binder, chitin nanofibers (CNF) as a crosslinker, and acidified halloysite nanotubes containing Apigenin (CA@e-HNTs) as an antimicrobial/cooling agent. The functional coating was sprayed on a poly(butylene adipate-co-terephthalate) (PBAT) substrate, integrating both radiative cooling capabilities and sustained antimicrobial properties. The hybrid film achieved subambient cooling through a high solar reflectance (90.5 %) and high mid-infrared emittance (94.0 %), resulting in a temperature of 6.2 ℃ below ambient under intense sunlight. When used for fresh food packaging, the hybrid functional film outperformed other commercially available food packaging materials in maintaining the quality of Agaricus bisporus and extending the storage time of fresh strawberries to 9 days. Moreover, the film exhibited excellent antibacterial and antioxidant properties. This zero-energy cooling technology with sustained antimicrobial characteristics has enormous potential for application in the preservation of fresh food, offering a more sustainable way to extend the shelf life of fresh produce and reduce food waste.

Closing the Perception-Reality Gap for Sustainable Fresh Food Plastic Packaging

The global discourse surrounding plastics has been marked by a profound perceptual schism, also for plastic packaging in the fresh food industry. The public opinion expresses mounting concerns in terms of such plastic packaging solutions. However, in many cases the unique material properties and the well-established methodology of Life Cycle Assessment (LCA) actually demonstrate the environmental advantage of plastics for food packaging. This paper delves into the chasm between the two perspectives, leveraging empirical evidence to resolve the divide.While performing both a consumer analysis and LCA, this paper underscores the potential for innovative, yet practical design solutions to harmonise the public opinion with counterintuitive positive environmental impacts. A transformative design solution that centres around the concept of shape and material renewal is proposed. It demonstrates how a simple, yet effective redesign can enhance both the environmental impact and consumer acceptance in the industry for mass-produced fresh food packaging. It emphasises the role of LCE in design, with a focus on the pre-consumer phase. The findings provide a practical approach, emphasising the need to reconcile theory with consumer desires, to forge a sustainable path forward in packaging design.

Humidity-adjustable functional gelatin hydrogel/ethyl cellulose bilayer films for active food packaging application

A sustainable functional bilayer film composed of gelatin hydrogel/ethyl cellulose was fabricated using a simple LBL casting method. The outer layer was hydrophobic ethyl cellulose (EC), while the inner layer was hydrophilic gelatin (GEL) hydrogel. Tannic acid (TA) served as a green cross-linker for GEL hydrogel preparation and as a reductant for AgNPs synthesis in-situ within the hydrogel network. Physicochemical and functional properties of the bilayer films containing different TA content were studied. When 3 wt% TA was added, the AgNPs@GT-3/EC bilayer film exhibited superior UV-light barrier, possessed desirable humidity-adjustable capability and oxygen barrier due to denser hydrogel network structure, and effectively inactivated foodborne pathogens S. aureus and E. coli with bacteriostatic rates of 99 %. The application results indicated that this bilayer film effectively maintained the postharvest quality of white button mushrooms and prolonged their shelf-life to 7 days under ambient storage, demonstrating its promising potential for fresh food packaging.

Questioning the disposability of plastic packaging: Consumer challenges to fresh food packaging market devices and their afterlives

ABSTRACT Disposable plastic packaging has been conceptualised as a market device that has effects on the functioning of economic markets. It is particularly influential in food retail environments but also has significant environmental consequences. Consumers are aware of these issues, and this paper addresses their questions and objections to the packaging market device for fresh food. Drawing on empirical insights from 28 interviews and 25 completed research diaries conducted as part of the ‘Reducing plastic packaging and food waste through product innovation simulation’ project, these contestations are explored in a number of ways. Firstly, it explores how such objections become possible and the role of unintended consequences of marketing arrangements. Secondly, conflicting ontologies of freshness are examined, as they also create the potential for objections. Thirdly, the paper engages with the role of responsibility, looking at how municipal recycling systems and packaging design enable contestations. Exploring these contestations contributes to an understanding of how we can address non-market effects of market devices, once they have left the physical spaces associated with market activity and moved into other spheres of activity. It also holds several contributions for debates concerning consumer engagement and acceptance of plastic packaging and plastics policy discourses more broadly.

Environmental Consequences of Shelf Life Extension: Conventional versus Active Packaging for Fresh-Cut Salads

The use of active coatings in fresh food packaging is an innovative technique that optimizes the functional properties of films, resulting in a longer product shelf life and reduced food waste. But, which is more sustainable, active packaging (AP) or conventional packaging (CP) for the packaging of fresh-cut products? To answer this research question, this study analyzes the environmental performance of AP during its life cycle for packaging a minimally processed fresh salad mix compared with CP, in terms of its manufacture and use. The AP is a bag that includes a bioactive component, oregano essential oil (OEO), which is an inhibitor of microbial growth, incorporated into an ethylene vinyl alcohol copolymer (EVOH) coating on a conventional polypropylene (PP) film. To this end, a Life Cycle Assessment (LCA) was carried out based on ISO 14040 and 14044, using the ReCiPe methodology. The results showed that using active packaging has a beneficial affect, reducing the amount of produced food by 30% compared with conventional packaging over the same period. The reductions in the studied impact categories were greater than 50% in most of them, with a 62% reduction in global warming. The proposed sensitivity analysis showed the difference between the disposal or treatment of waste generated by the packaging production process and the packaged product, indicating that this step is of great importance for the environmental impacts and sustainability of this process. In 80% of the scenarios analyzed, the AP achieved better results than the CP in terms of damage categories.

MOF-Based Active Packaging Materials for Extending Post-Harvest Shelf-Life of Fruits and Vegetables.

Active packaging that can extend the shelf-life of fresh fruits and vegetables after picking can assure food quality and avoid food waste. Such packaging can prevent the growth of microbial and bacterial pathogens or delay the production of ethylene, which accelerates the ripening of fruits and vegetables after harvesting. Proposed technologies include packaging that enables the degradation of ethylene, modified atmosphere packaging, and bioactive packaging. Packaging that can efficiently adsorb/desorb ethylene, and thus control its concentration, is particularly promising. However, there are still large challenges around toxicity, low selectivity, and consumer acceptability. Metal-organic framework (MOF) materials are porous, have a specific surface area, and have excellent gas adsorption/desorption performance. They can encapsulate and release ethylene and are thus good candidates for use in ethylene-adjusting packaging. This review focuses on MOF-based active-packaging materials and their applications in post-harvest fruit and vegetable packaging. The fabrication and characterization of MOF-based materials and the ethylene adsorption/desorption mechanism of MOF-based packaging and its role in fruit and vegetable preservation are described. The design of MOF-based packaging and its applications are reviewed. Finally, the potential future uses of MOF-based active materials in fresh food packaging are considered.

Optimization of stretch film former of fresh food packaging machine

Current research on fresh food packaging machines focuses on vertical and horizontal sealing. Compared with the conventional pillow packaging machine, the fresh food packaging machine still presents deficiencies regarding the feeding and forming ability of stretch film. This paper presents a step former for the stretch film to integrate the existing forming mechanism. First, by analyzing the movement diagram of the stretch film on the support plate, the optimal inclination angle of the stretch film during the process of feeding on the upper part of the support plate, and the center position of the second directional wheel on the upper part of the support plate was found, it can ensure that the stretch film in the process of feeding and forming has the minimum tension and not be broken. In addition, based on the above-mentioned, the support plate and the directional wheel were simulated in software. The 2 mm 304 stainless steel support plate and different plastic combinations of directional wheels were the optimal choices.

Characterization and application of active films based on commercial polysaccharides incorporating ZnONPs

In the face of the environmental problems caused by using food packaging composed of non-renewable sources, the aim of this study was producing a new antimicrobial film, biodegradable and with UV barrier based on commercial κ-carrageenan/starch polysaccharides loaded zinc oxide nanoparticles (ZnONPs) for the first time by casting method. Different formulations of κ-carrageenan/starch/ZnONPs were extensively characterized. The X-ray patterns displayed diffraction peaks characteristics of the crystallographic plane of ZnONPs. The formation of the material composite was confirmed by specific signals in the FTIR spectrums and endothermic peak shift after ZnONPs addition. The ZnONPs (1.5 and 2 %) produce a more resistant material. The analysis of SEM (cracks remotion of film surface), mechanical properties (higher elongation at rupture and tensile strength), and opacity (low transparency) confirm this. Still, ZnONPs at 2 % produce a hydrophobic surface, justified by lower moisture content, water solubility, and higher WCA. The ZnONPs promoted UV barrier and antimicrobial activity against Escherichia coli, Salmonella Typhimurium, and Staphylococcus aureus microorganisms. Thus, the new active material was applied as a coating on fresh strawberries and delayed the ripening of the fruit, extending its shelf life. Therefore, we produced, characterized, and applied an active material with potential application in fresh food packaging.

White Ginger Nanocellulose as Effective Reinforcement and Antimicrobial Polyvinyl Alcohol/ZnO Hybrid Biocomposite Films Additive for Food Packaging Applications

Polyvinyl alcohol (PVA) has been used in packaging applications due to its biocompatibility and biodegradability. However, this non-toxic synthetic material belonging to a highly hydrophilic polymer has poor resistance to wet environments, no antibacterial activity, and low tensile and thermal properties. This study aims to prepare and characterize a PVA-based biocomposite film mixed with antimicrobial white ginger nanocellulose (GCNF) and zinc oxide (ZnO) nanoparticles. The film was processed using GCNF (0.1 g) or/and ZnO nanoparticles (0.5 g). The results confirm that the GCNF/ZnO/PVA-based film presents the strongest antimicrobial activity and the highest thermal resistance. This film also had the best value in tensile strength (19.7 MPa) and modulus (253.1 MPa); 63.9% and 117.9%, respectively higher than purce PVA. Its elongation at break was 56.6%, not statistically significantly different from the pure PVA film. Thus, this PVA-based hybrid biocomposite film reinforced by GCNF and ZnO has excellent potential for fresh food packaging in industrial applications.

Effect of plasma treatment on improving liquid retention capacity of capillary recesses for food packaging applications

Liquid residue is a major issue in fresh food packaging, especially for meat products. This work investigates capillary recesses directly integrated into PET packaging film, with targeted plasma treatment of the recesses to enhance their liquid retention capacity. Localised oxygen plasma treatment (oxygen flow rate: 80 cm3/min, pressure: 0.14 mbar, power: 240 W) of PET recesses introduced polar oxygen groups onto their surface and increased their wettability. It is proposed that the difference in wetting characteristics of the recesses and rest of the packaging surface enhanced the capillary valve effect, which dramatically increased the liquid retention capacity. Untreated recess samples (diameter: 9 mm) had retention capacity of around 0.70 g, which increased to 1.50 g after localised O2 plasma treatment. Even after aging of over 60 days, the plasma-treated recesses maintained the enhanced retention capabilities. The estimated resulting retention capacity of recesses of diameter 9 mm was 2972 ± 62 mL/m2, which is comparable with conventional absorbent pads (3000 mL/m2). This demonstrated the viability of applying plasma treatment in food packaging to effectively isolate any excessive exudate using only the packaging film.

Design and simulation of key mechanism for transverse sealing of fresh food packaging machine

In order to improve the freshness and safety of fresh food, packaging is necessary for the processing industry of agricultural products. At present, the packaging of fresh food in China is mainly manual packaging, which has high labor intensity and low production efficiency. In response to this situation, this study focused on the transverse sealing device of the fresh food packaging machine. The device completed the transverse sealing operation through the cooperation of two main mechanisms, including an up wind box and an anthropomorphic hand folding mechanism. The anthropomorphic hand folding mechanism was composed of roller, cylinder and lower wind box. This paper makes a study of design and simulation of key mechanism for transverse sealing of fresh food packaging machine, improving the completion of the transverse sealing of the packaging machine. The experiment showed that the designed structure basically satisfied the functional requirements of the fresh food packaging machine for the sealing operation of the transverse sealing device. And the optimal parameter of the air outlet of the up wind box was 640 mm2, the lower wind box of anthropomorphic hand folding mechanism was 19 air outlets with a diameter of 2 mm.

Development of polyvinyl alcohol/β-cyclodextrin antimicrobial nanofibers for fresh mushroom packaging

Under the optimal conditions, a crosslinked electrospun polyvinyl alcohol/cinnamon essential oil/β-cyclodextrin (CPVA-CEO-β-CD) nanofibrous films for sustained release of antimicrobials were successfully prepared. Cinnamon essential oil (CEO) can be sustainably released due to CPVA-CEO-β-CD nanofibers complex delivery systems. The chemical crosslinking and physical welding achieved simultaneously by glutaraldehyde atomization fumigation, making fibers more suitable for fresh food packaging. Nanofibrous films were characterized in terms of SEM, ATR-FTIR, DSC, water contact angle analysis and antibacterial trials. ATR-FTIR and DSC data indicated that CEO was encapsulated in a β-CD cavity and they coexisted in PVA nanofibers. The water contact angle of the crosslinked PVA nanofibrous films increased with CEO and the values were always below 90°. Crosslinked nanofibers possessed fine properties in vitro antibacterial against Staphylococcus aureus and Escherichia coli. Furthermore, CPVA/β-CD/CEO nanofibrous films delayed decay of mushroom during storage, indicating their potential implementation in active food packaging.

An attributional Life Cycle Assessment application experience to highlight environmental hotspots in the production of foamy polylactic acid trays for fresh-food packaging usage

Food packaging systems mainly serve to contain and protect foods during their shelf-lives. However, it is well known that a package is responsible for several environmental impacts associated with its entire life-cycle. Therefore, package design should be developed taking into account not only cost, food shelf-life and safety, as well as user-friendliness, but also environmental sustainability. To address and improve this latter issue, environmental evaluation methodologies need to be applied: Life Cycle Assessment (LCA) is one amongst them, and can be considered a valid tool for this purpose. Indeed, it has been long applied in the food packaging field to highlight both environmental hotspots and improvement potentials for more eco-friendly products.In this context, this paper reports upon an LCA application experience in the production of foamy Polylactic Acid (PLA) trays for fresh-food packaging applications.The study highlighted that the highest environmental impacts come from the production and transport of the granules, so remarking the need to search for alternative biopolymers. In this regard, the results of this study will form the base for another one regarding the assessment of second-generation PLA granules, namely those produced by processing both wastes and wastewaters from starchy crop cultivation systems and processing plants.

Polylactic acid trays for fresh-food packaging: A Carbon Footprint assessment

This paper discusses application of Carbon Footprint (CF) for quantification of the 100-year Global Warming Potential (GWP100) associated with the life cycle of polylactic acid (PLA) trays for packaging of fresh foods. A comparison with polystyrene (PS)-based trays was done considering two different transport system scenarios for PLA-granule supply to the tray production firm: a transoceanic freight vessel and an intercontinental freight aircraft. Doing so enabled estimation of the influence of the transportation phase on the GHG-emission rate associated with the PLA-trays' life cycle. From the assessment, the GWP100 resulted to be mainly due to PLA-granulate production and to its transportation to the tray manufacturing facility. Also, the study documented that, depending upon the transport system considered, the CF associated with the life cycle of the PLA trays can worsen so much that the latter are no longer GHG-emission saving as they are expected to be compared to the PS ones. Therefore, based upon the findings of the study, it was possible for the authors to understand the importance and the need of accounting for the transport-related issues in the design of PLA-based products, thus preserving their environmental soundness compared to traditional petroleum-based products.In this context, the study could be used as the base to reconsider the merits of PLA usage for product manufacturing, especially when high distances are implied, as in this analysed case. So, the authors believe that new research and policy frameworks should be designed and implemented for both development and promotion of more globally sustainable options.

Bio‐based multilayer barrier films by extrusion, dispersion coating and atomic layer deposition

ABSTRACTA single biopolymer film rarely has a competitive edge against synthetic films. One solution is to combine several layers with different properties into multilayer structures. In this way, for example, the barrier properties of bio‐based materials can be improved. In this study, the multilayer films are produced by combining three different techniques/materials: 1) dispersion coating (cellulose nanofibrils, CNF), 2) atomic layer deposition (Al2O3; aluminum oxide), and 3) extrusion coating (polyglycolic acid, PGA). Especially the CNF and PGA‐containing multilayer films show promising oxygen barrier improvements at different humidities. Thin inorganic coatings are brittle and sensitive toward stresses during converting, which may limit their use in such specific multilayer structures. The developed bio‐based films largely fulfill the barrier requirements of fresh food packaging. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42260.

Fresh food packaging design: A requirement driven approach applied to strawberries and agro-based materials

To overcome the limitations of current trial and error approaches used to design food packaging, a requirement driven approach was adapted from the software and service industries to the field of fresh fruits and vegetable packaging. Based on 5 steps, it relies on the knowledge of produce needs and the use of modeling tools to turn produce requirements into packaging properties before designing the packaging. It was then successfully applied to dimension and design an active packaging, tailor made for optimal preservation of strawberries at 20 °C. The solution consisted in a PET punnet providing protection against physical damage and a lid ensuring both gas transfer for optimal atmosphere and release of an active agent acting against mold growth. This active lid was made of wheat gluten proteins containing 2-nonanone that was quickly released only in high RH conditions in an amount equal to the minimal inhibition dose for Botrytis cinerea. Design of packaging for fresh produce such as fruits and vegetables is still mainly based on a trial and error approach (often referred as “pack and pray”) that does not ensure conception of an optimal packaging for produce preservation. The non-optimal character of existing packaging is one of the main causes of fresh fruit and vegetable losses along the supply chain. This study proposes an alternative approach to design optimal packaging for fresh and respiring produce: the requirement driven approach. This approach was adapted from the field of software and service industries to the specificity of fresh produce packaging one. It takes into account the needs of the produce (e.g. physical protection, microbial protection or optimal atmosphere for preservation) from the very beginning of the conception process to reduce the risks of inadequacy between the packaging and the produce. In addition to knowledge of the produce physiology and needs, this approach relies on the use of modeling tools to turn produce requirements into packaging properties before designing the packaging. The efficiency of such method was demonstrated through a case study on strawberry packaging. Given the increasing quantity of data available on produce physiology and needs, and the online, free to use and user friendly character of recent MAP modeling tools such as Tailorpack (www.tailorpack.com), generalization of the requirement driven approach proposed in this study could be of major interest for the fresh fruits and vegetable packaging industry. It should help to design optimal packaging for specific produce and thus reduce risk of losses along the supply chain by improving preservation.

Carvacrol and Thymol for Fresh Food Packaging

Active packaging is becoming an emerging food technology to improve quality and safety of food products. One of the most common approaches is based on the release of antioxidant/antimicrobial compounds from the packaging material. In this work an antifungal active packaging system based on the release of carvacrol and thymol was optimized to increase the post-harvest shelf life of fresh strawberries and bread during storage. Thermal properties of the developed packaging material were determined by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Volatile compounds in food samples contained in active packaging systems were monitored by using headspace solid phase microextraction followed by gas chromatography analysis (HS-SPME- GC-MS) at controlled conditions. The obtained results provided evidences that exposure to carvacrol and thymol is an effective way to enlarge the quality of strawberries and bread samples during distribution and sale.

Structural Control of SiOx Coatings and their Migration-Resistance Properties

Diethylhexyl phthalate (DEHP) is a kind of plasticizers which is generally used in plastics packaging materials to provide the flexibility. Especially in PVC films, a large amount of DEHP used makes it possibility of the widespread usage of PVC in the fresh food packaging market. But recent researches proved that DEHP can be easily migration into food and food stimulant. It causes reproductive disorders, mutation, carcinogenicity, and other genetic toxicity to all mammals. Hence blocking the migration of DEHP from the plastic to the foods becomes very important issue for the food safety. In this work, the migration kinetics of DEHP was explored. We achieved that the migration of DEHP can be well controlled through coated nano-scale SiOxbarrier layer on the surface of PVC films, and the plasma enhanced chemical vapor deposition (PECVD) process is a very efficient way to prepare SiOxcoatings on the plastic surface. It is also noticed that there is a relationship between the migration-resistance properties and coating structure through Fourier transform infrared spectroscopy (FTIR) for the chemical composition analysis, scanning electron microscope (SEM) for the topography investigation of the coating surfaces, surface profilemeter for the thickness measurement of coatings, and high-performance liquid chromatography (HPLC) for the barrier property evaluation of coatings at last. We conclude that the coatings can perfectly block the migration of the DEHP from plastics to their contents. When the deposition conditions of SiOxcoatings were optimized, i.e. 50W of the discharge power, 4:1 of ratio of O2: HMDSO, and ca.100 nm thickness of SiOx, the 71.2% DEHP, compared to the control PVC film, was effectively barriered.