Food Packaging Applications Research Articles

Preparation and characterization of a chitosan-gentamicin derivative and its effect on tropical fruit preservation

Applications of chitosan (CS) are hindered by its weak antimicrobial ability, poor solubility in basic and neutral solutions, structural modification is needed to improve its functional properties. Herein, a new chitosan-gentamicin derivative (CS-GT) was successfully synthesized via protection, regioselective bromination, nucleophile substitution reaction, and deprotection. Characterization techniques confirmed the successful introduction of GT onto the C-6 position of CS with a grafting rate of 76.19%. The additional amino groups provided by GT decreased the crystallinity and thermal stability of CS-GT, while enhancing its solubility in neutral and alkaline solutions. Compared to CS, CS-GT exhibited 2.50 and 2.41 times higher antibacterial activities against Escherichia coli and Staphylococcus aureus, respectively. Besides, an active packaging coating was develop by incorporating glycerol into CS-GT. The hydrogen bond networks formed within coatings endowed them good thermal stability and tightly uniform morphology. Furthermore, increasing CS-GT from 1% to 3% improved the coating's ultraviolet resistance and flexibility, but reduced its waterproof performance, visual appearance, and water barrier properties. Preservation experiments with papaya and litchi showed that CS-GT coatings effectively inhibited microbial growth and maintained quality and appearance up to 16 and 8 days of storage, respectively. In conclusion, CS-GT show promising potential for applications in food packaging.

Preparation, characterization, antimicrobial evaluation, and grape preservation applications of polyvinyl alcohol/gelatin composite films containing zinc oxide@quaternized chitosan nanoparticles

This study employed a precipitation method to synthesize zinc oxide@quaternised chitosan nanoparticles (ZnO@QAC NPs) containing different concentrations of zinc oxide, namely ZnO@QAC-2, ZnO@QAC-4, and ZnO@QAC-6. Subsequently, these nanoparticles were incorporated into matrices consisting of gelatine (Gn) and polyvinyl alcohol (PVA) separately, which were prepared by casting to form a biodegradable film. We assessed the physicochemical properties of ZnO@QAC NPs and physicochemical characteristics, antioxidant properties, antimicrobial activity and grape preservation efficacy of the film. Compared to the control group, the films showed a reduction in water vapor permeability by >9.38 %, an increase in tensile strength by over 51.95 %, over 70 % scavenging of ABTS free radicals, and good biocompatibility. Additionally, the antimicrobial activity of the films containing ZnO@QAC-6 increased by 37.6 %. In the grape preservation experiment, the weight loss of grapes wrapped in ZnO@QAC-2 film was reduced by 40.13 % on day 15 compared to unwrapped grapes. These results demonstrate that ZnO@QAC/PVA/Gn films have considerable potential for food packaging applications.

Bio-inspired fabrication of thin films via surface amidation of TEMPO-oxidized cellulose nanocrystals for improved UV-shielding properties

Ultraviolet (UV) radiation impacts various aspects of human beings, and there has been significant interest in membrane materials with UV shielding. However, conventional ultraviolet shielding materials are typically petroleum-based polymers like polyethylene, which pose challenges in terms of degradation and reusability, leading to environmental pollution and other issues. The development of environmentally friendly bio-based UV shielding film materials from wood fiber raw materials holds immense importance for sustainable development. In this study, TEMPO-oxidized cellulose nanocellulose crystals (TOCNC) were utilized as the starting material to obtain modified nanocellulose suspension through amination with aniline and acetamide. Subsequently, nanocellulose films were prepared and characterized for their morphology and structure analysis. With the presence of carboxyl groups on TOCNC along with the incorporation of functional groups such as benzene rings, the absorption rate of the TOCNC composite film reaches 93.2 % across the entire ultraviolet absorption spectrum, significantly enhancing its UV shielding performance. The proposed film exhibits great potential for applications in UV-sensitive food packaging, electronic product packaging materials, plastic films, etc.

Characterization of zein nanofiber mats encapsulated with Foeniculum vulgare and Carum carvi essential oils as active packaging materials

This study aimed to encapsulate Foeniculum vulgare and Carum carvi essential oils (FVO and CCO) into the zein (ZN) nanofibers using an electrospinning technique and examine their application in retarding the growth of bacterial pathogens in ground beef meat during refrigerated storage conditions. The main fractions of FVO included trans-anethole (37.98%), α-fellandrene (15.09%), fenchone (10.58%), and tarragon (7.58%). CCO's major chemical compositions were also identified as α-terpinene (19.67%), α-terpinene-7-al (18.86%), p-menthatriene (16.90%), and cuminaldehyde (15.96%). The Fourier transform infrared spectroscopy analysis verified the molecular interaction between FVO/CCO and the ZN polymer. The thickness, tensile strength, elongation at break, and water vapor permeability of the nanofiber mats were in the range of 0.20–0.22 mm, 6.01–9.22 MPa, 5.57%–10.78%, and 1.05–2.72 × 10‾14 kg m/m2 s Pa, respectively. The initial count of 5 log CFU/g of Staphylococcus aureus, Listeria monocytogenes, and Yersinia enterocolitica in ground beef meat packaged with ZN + FVO 1 mL/100 mL + CCO 1 mL/100 mL nanofiber mats, as the best group, reached <1.00, 2.52, and 3.13 log CFU/g, respectively, at the end of the study (day 10), suggesting that the designated nanofiber mats can be utilized for antimicrobial food packaging applications.

Development of curcumin integrated smart pH indicator, antibacterial, and antioxidant waste derived Artocarpus lakoocha starch-based packaging film

Monitoring of food freshness is considered one of the crucial challenges for both customers/consumers and the food industries. In this study, we developed a curcumin-based starch film (F1) for pH-sensitive intelligent food packaging application. The starch was obtained from waste seeds of Artocarpus lakoocha (NS-MJF). The native starch underwent various physical and chemical modifications to yield modified starches (S1 [Autoclave heat treated], S2 [osmotic-pressure treated], S3 [citric acid treated]). The native starch was then used further for the formation of curcumin (2.5 % w/w)-based film (F1). We had analyzed these starches for solubility, colour analysis, biodegradability, oil absorption capacity, and moisture content, etc. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) revealed favourable microstructures. The addition of curcumin to the starch enhanced the contact angle and elongation at the break of the resulting films. Antioxidant and antimicrobial assays, along with real-time freshness monitoring of chicken fillets, were also conducted. Thus, our findings may contribute to the optimization of pH-responsive biopolymer-based films for intelligent poultry packaging, promising advancements in food preservation and safety.

Enhancing the Mechanical Strength and Thermal Stability of Polylactic Acid (PLA) with the Addition of Epoxidized Waste Cooking Oil (EWCO)

Polylactic Acid (PLA) comes from renewable resources, has a reasonable biodegradability rate, and is used in biomedical, food packaging, textiles, and agricultural applications. PLA offers high mechanical strength and the ability to compost, similar to polyethylene terephthalate (PET) and nylon. However, the brittleness of PLA has always limited its usage. Therefore, bio-based plasticizers in the biopolymer matrices can increase flexibility (elasticity), durability, and workability. This study aims to determine the optimal blending ratio for the PLA blended with epoxidized waste cooking oil (EWCO) to enhance the mechanical and thermal properties of PLA/EWCO. The mechanical strength test consists of the hardness test (N/mm&lt;sup&gt;2&lt;/sup&gt;), flexural strength (MPa), and impact energy (kJ/m&lt;sup&gt;&lt;/sup&gt;) adopted to evaluate the plasticizing characteristics. The thermal stability analysis involves glass transition temperature (T&lt;sub&gt;g&lt;/sub&gt;) (°C), cold-crystallization temperature (T&lt;sub&gt;cc&lt;/sub&gt;) (°C) and melting temperature (T&lt;sub&gt;m&lt;/sub&gt;) (°C). The blending ratio is 97.5PLA/2.5EWCO, 95PLA/5EWCO, 92.5PLA/7.5EWCO and 90PLA/10EWCO. As a result, 97.5:2.5 of PLA/EWCO reduces intermolecular interactions by stimulating more free volume in biopolymer chains’ mobility and enhancing the flexibility and elasticity of the PLA blends. Ultimately, the brittleness of PLA decreased with increasing EWCO bio-based plasticizer.

Preparation and characterisation of fish skin collagen–chitosan–cinnamon essential oil composite film

SummaryThe composite film with collagen as the main component has been widely used due to its characteristics of non‐toxicity, environmental protection and health. Fish skin, a by‐product of fish, is an excellent source of collagen. Thus, collagen was extracted from an under‐utilised species, Atlantic cod (Gadus morhua) skin, and the composite film of fish skin collagen–chitosan–cinnamon essential oil was prepared by casting. The effects of the ratio of collagen to chitosan (2:8, 4:6, 5:5, 6:4, 8:2) and the concentration of essential oil (0%, 0.1%, 0.2%, 0.3%, and 0.4% (v/v)) on the composite film were studied. The structures of the composite films were analysed using scanning electron microscopy (SEM), Fourier transforms infrared spectroscopy (FTIR), and X‐ray diffractometry (XRD). The collagen content of Atlantic cod skin is approximately 50.12%, which is significantly higher than that found in basa fish and Nile tilapia (P &lt; 0.05). The content of hydroxyproline was 4.51%. Analyses of tensile strength, elongation at break, water vapor permeability, and water solubility showed Co4Ch6 (Co:Ch = 4:6) had the optimal comprehensive performance, and Co4Ch6–0.2 (Co4Ch6 with 0.2% CEO) had high water resistance in the high‐humidity environment. As the CEO concentration rose, the composite films' infrared absorption bands were enhanced in amplitude, and the XRD peaks were gradually intensified, indicating the internal crystallinity and, thereby, the opacity of the composite films were improved. The bacteriostasis zones Co4Ch6–0.4 against Escherichia coli and Staphylococcus aureus were 2.02 cm and 1.73 cm, respectively. The DPPH radical scavenging rate of Co4Ch6 rose with the increase in CEO concentration, and the DPPH radical scavenging rate of C04Ch6–0.4 was up to 48.56%. Thus, the composite films prepared from fish skin collagen, chitosan, and cinnamon essential oils have outstanding mechanical properties, barrier ability, and antimicrobial activity and are promising for application in food packaging and storage. In addition, the composite films showed a potential antioxidation ability, which might be used as green bioactive films to preserve nutraceutical products.

Biodegradable chitosan hydrogel film incorporated with polyvinyl alcohol, chitooligosaccharides, and gallic acid for potential application in food packaging

The food and beverage industry worldwide is trying to switch to using environment-friendly and bio-degradable materials in food packaging to avoid environmental concerns of using petroleum-derived plastic (synthetic polymers) materials. In this study, chitosan (CH) hydrogel films were fabricated by using its derivative chitooligosaccharides (COS) as an additive, polyvinyl alcohol as a plasticiser, and bioactive gallic acid as a cross-linker. The physical, mechanical, structural, barrier (e.g., moisture, water vapour permeability (WVP), and UV-barrier property), thermal properties, and biodegradation patterns of fabricated films were investigated. The use of bio–composite in CH films exhibited a synergistic effect. A film with a homogenous/smooth surface and excellent mechanical and thermal properties was obtained. Additionally, incorporating COS and gallic acid reduced the moisture content, WVP, and transparency. Moreover, the films exhibited good colour, strong UV-barrier properties, and good biodegradable capacity in soil. The results suggest that eco-friendly CH hydrogel films have promising potential to be used in food packaging.

Enhanced composite Co-MOF-derived sodium carboxymethyl cellulose visual films for real-time and in situ monitoring fresh-cut apple freshness

Natural biopolymers have extensively applications in intelligent food packaging due to their renewable nature, easy availability, environmental-friendly, low-cost and excellent processibility. Recently, the integration or embedding of nanocomposites on polymer substrates to improve the multi-faceted performance of packaging materials has attracted widespread attention. Herein, the irregular spherical Co-based metal-organic framework (Co-MOF) loaded with phenol red (PR) and bromothymol blue (BTB) were fabricated, resulting in absorbed nanocomposites Co-MOF/PR and Co-MOF/BTB. Afterward, the nanocomposites were integrated into a sodium carboxymethyl cellulose (CMC-Na) substrate to prepare a CO2-responsive packaging material (CMC-Na/PR/Co-MOF and CMC-Na/BTB/Co-MOF) for real-time and in-situ monitoring apple freshness. The synthesis of Co-MOF and the hydrogen-bonding interactions between MOF and pigments adsorption were confirmed. The advantages exhibited by the film with adding Co-MOF, including excellent hydrophobicity and water resistance, improved time-temperature stability and mechanical properties, were explored. Notably, the Co-MOF-based composite film exhibited enhanced UV–visible barrier, anti-migration performance of pigment, and thermal stability. Finally, a significant linear response (R2 = 0.9923 and 0.9781) between the total color difference values (ΔE) of Co-MOF-based film and hardness and total soluble solids (TSS) of fresh-cut Fuji apples at 4 °C was demonstrated, respectively. These findings indicate the significant potential of CMC-Na-based composite film containing multifunctional MOF nano-filler as a visual monitoring system, which will pave the way for fresh-cut fruit intelligent packaging.

Preparation of novel cellulose from outer skin and seeds of Manilla tamarind (Pithecellobium dulce)-Ag/TiO2/Chitosan nanocomposite and its biological properties

The current study was aimed to prepare a novel composite thin film from Manilla tamarind (MC) outer skin and seeds with silver nanoparticles (AgNPs) and TiO2 nanoparticles and blended with chitosan (Ch). NaBH4 was used to prepare MC/AgNPs composite utilizing the reduction process. Solvent casting method was used to prepare a thin film of the composite material MC/AgNPs//TiO2/Ch. Field emission scanning electron microscopy (FE-SEM) displayed the diffusion of Ch and AgNPs and TiO2 on the surface of MC network. The average particle size of AgNPs distributed on the MC is between 47 and 48 nm. Nanotitania was prepared by sol-gel method using titanium tetraisopropoxide and isopropanol. Antibacterial studies show that the nanocomposite exhibited higher inhibition effects against Staphylococcus Aureus and Escherichia Coli than isolated Manilla cellulose. The photodegradation of nanocomposite showed 77 % within just 10 min. Antioxidant studies were analyzed by using DPPH radical at 517 nm. The percentage of antioxidant activity of MC and nanocomposite showed as 27.15 % and 30.41 % respectively with DPPH radical. The high capability of antibacterial and photocatalytic effects finds application in food packaging applications and wastewater treatment.

A synergistic influence of gallic acid/ZnO NPs to strengthen the multifunctional properties of methylcellulose: A conservative approach for tomato preservation

Biodegradable and sustainable food preservation materials have gained immense global importance to mitigate plastic pollution and environmental impact. Biopolymers like cellulose offer significant advantages for food preservation, including biodegradability and the ability to extend shelf life. Therefore, the present study aims to prepare gallic acid (GA) and zinc oxide nanoparticles (ZnO NPs) incorporated methylcellulose (MC) composite films by employing a solvent casting technique. The homogeneous SEM micrographs and FTIR spectra evidenced high compatibility among MC and GA/ZnO NPs. The UV barrier capacity, mechanical properties and surface hydrophobicity are remarkably enhanced by GA/ZnO NPs. However, the water vapour permeability and oxygen permeability of MGZ films were reduced by 49.19 % and 57.75 % respectively. Moreover, the MGZ films demonstrated exceptional antioxidant efficacy (∼94.48 %) and inhibition against food-borne pathogens such as B. subtilis, S. aureus (Gram-positive), E. coli, P. aeruginosa (Gram-negative), and C. albicans fungi. Furthermore, the GA/ZnO NPs extended the shelf life of MGZ coated tomato samples up to 27 days and exhibited controlled microbial growth after the preservation study. These results support the application of MGZ films as suitable and effective coating materials for food packaging applications.

Eco-friendly Blends of Polylactic Acid and Polyhydroxybutyrate Enhanced with Epoxidized Soybean Oil Methyl Ester for Food-Packaging Applications

Eco-friendly Blends of Polylactic Acid and Polyhydroxybutyrate Enhanced with Epoxidized Soybean Oil Methyl Ester for Food-Packaging Applications

Development of crosslinked gelatin films through Maillard reaction and reinforced with poly(vinyl alcohol) for active food packaging

In order to improve the functionality of natural gelatin films for active food packaging applications, a combined strategy of crosslinking via Maillard reaction and blending enhancement incorporated with poly(vinyl alcohol) (PVA) was explored. In this study, when the mass ratio of gelatin to glucose was 10:1, Maillard reaction of crosslinked gelatin films was the highest, UV absorption and browning index reached the maximum. Infrared analysis showed that PVA could form strong interfacial interactions with gelatin matrix. The presence of PVA could significantly improve the toughness, water absorption, transparency, and oxygen barrier properties of crosslinked gelatin films. When the amount of PVA reached 5 %, elongation at break and oxygen barrier properties of crosslinked gelatin films were improved by 76.7 % and 47.9 % compared with pure crosslinked gelatin film. Even when the amount of PVA reached 10 %, UV absorption (at 315 nm) of crosslinked gelatin films still exceeded 98.7 %. The addition of PVA could accelerate the dissolution and swelling of crosslinked gelatin films, promoting the migration and release of active substances (Maillard reaction products (MRPs)). The two antioxidant activities tests (DPPH and ABTS method) achieved the highest radical scavenging rates of 71.6 % and 91.2 %, respectively, with corresponding PVA addition of 5 % and 7.5 %. After continuing to add PVA, antioxidant activities began to significantly decrease, which was directly related to the decrease in the generation of MRPs. Therefore, crosslinked gelatin films reinforced with appropriate amount of PVA can be considerable potential as active films for renewable food packaging applications.

Multilayer Film Comprising Polybutylene Adipate Terephthalate and Cellulose Nanocrystals with High Barrier and Compostable Properties.

In the present study, a multilayer, high-barrier, thin blown film based on a polybutylene adipate terephthalate (PBAT) blend with polyhydroxyalkanoate (PHA), and composed of four layers including a cellulose nanocrystal (CNC) barrier layer and an electrospun poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) hot-tack layer, was characterized in terms of the surface roughness, surface tension, migration, mechanical and peel performance, barrier properties, and disintegration rate. The results showed that the film exhibited a smooth surface. The overall migration tests showed that the material is suitable to be used as a food contact layer. The addition of the CNC interlayer had a significant effect on the mechanical properties of the system, drastically reducing the elongation at break and, thus, the flexibility of the material. The film containing CNCs and electrospun PHBV hot-tack interlayers exhibited firm but not strong adhesion. However, the multilayer was a good barrier to water vapor (2.4 ± 0.1 × 10-12 kg·m-2·s-1·Pa-1), and especially to oxygen (0.5 ± 0.3 × 10-15 m3·m-2·s-1·Pa-1), the permeance of which was reduced by up to 90% when the CNC layer was added. The multilayer system disintegrated completely in 60 days. All in all, the multilayer system developed resulted in a fully compostable structure with significant potential for use in high-barrier food packaging applications.

Use of modified polycaprolactone polymer in food packaging applications: a review

Objective: Plastic production in the world is constantly increasing and plastics have been degraded in nature for many years. This situation turns into a major environmental disaster that people and living organisms will encounter. In addition, packaging films that can be applied to foods safely and extend the shelf life of foods with their functional properties are needed. Polycaprolactone (PCL) is a biodegradable polymer produced by synthetic processes and has been frequently investigated in food packaging studies in recent years. Due to its flexibility, biocompatibility and thermoplasticity, the use of PCL and its copolymers in packaging film applications is becoming widespread. Disadvantages such as low mechanical and thermal resistance can be eliminated by adding fillers, mixing with other polymers or using multi-layers. This study aims to compile recent studies on the use of PCL polymer modified by various methods as food packaging. Conclusion: In the literature, there are many interesting studies on the making composite of PCL with different methods. Nanoclays to improve mechanical and gas barrier properties; nanometals and plant materials to impart antimicrobial properties; innovative additives such as oxygen scavengers, photosynthesizing agents, antimicrobial peptides are used in the modification of PCL. In this review, it was revealed that the modifications contribute to PCL polymer in terms of stiffness and gas barrier properties and add antimicrobial and antioxidant character to the polymer.

Thermal and heat-sealing properties of polyvinyl alcohol/cellulose nanocrystals-based nanocomposites for food packaging

Food packaging materials require advanced properties (UV barrier and antioxidant/antimicrobial) to extend the shelf-life of packaged products. Recently, we have developed biodegradable nanocomposites by incorporating cellulose nanocrystals (CNCs) and active agents (titanium dioxide nanoparticles and apple peel extract) into polyvinyl alcohol (PVA). These nanocomposites exhibited advanced properties and many demonstrable advantages in food packaging. Herein, the thermal stability, melting behaviors, and heat-sealing properties of these nanocomposites are investigated to demonstrate their potential production at the industrial level and practical use. The results showed that the PVA/CNC-based nanocomposites exhibited thermoplastic properties and had sufficient heat-sealability. The PVA/CNC-based nanocomposites presented lower melting temperatures (217.7–224 °C) than pure PVA (226 °C). Furthermore, their seal strengths (15.1–1238.1 N/m) are similar to those of petroleum-based food packaging polymers (polypropylene: 300–1100 N/m, low-density polyethylene: 677.7 N/m) and can be controlled by adjusting the sealing temperature, which is useful for various food packaging applications.

Chitosan based Nanocomposites: Its Synthesis, Characterization and Applications in Various Fields: A Review

Nanocomposites: modern material are multiphase martial composed of one or many phases of less than 100 nm dimensions. Polymer –matrix nanocomposites are composed of polymer matrix reinforced with nanoscale fillers. Chitosan is the most abundant biopolymer after cellulose, extracted from chitin present in insect exoskeleton fungal cell wall, and crustaceans. Chitosan gains the attention of many researcher because of its unique properties like biodegradable, plant growth regulator, biocompatible, antimicrobial agent and nontoxic. Chitosan nanocomposites combine the benefits of chitosan with enhanced properties provided by nanoparticles making them versatile and high performing material. Chitosan nanocomposites has numerous application in industries, biomedical, food packaging, and environmental remediation. This review focuses on the Chitosan nanocomposites synthesis, their characterization and applications in various fields.

Biodegradable chitosan-based biofilms incorporated with Camellia oleifera residue protein for food packaging

Biodegradable films have attracted considerable eco-friendly applications in food packaging, preservation, and separation. This research used a protein mixture containing polyphenols, flavonoids, and tea saponins extracted from Camellia oleifera residues through alkaline dissolution and acid precipitation to prepare biodegradable films. By blending the protein with chitosan, the obtained biopolymer films exhibited improved properties such as hydration, permeability, strength and flexibility, while also showing reduced water solubility. In addition, chitosan-based C. oleifera residue protein biofilms also possessed a significant enhancement in the biofilm's antioxidant, antimicrobial and biodegradable capabilities. Scanning electron microscopy revealed slight irregularities on the film surface when augmented with C. oleifera residue protein, leading to increased cross-sectional roughness and porosity compared to pure chitosan films. These enhancements notably prolonged the shelf life of perishable fruits such as strawberries. Overall, this research used a protein mixture strength, and flexibility while showing reduced also significantly enhanced the biofilm's antioxidant, creating eco-friendly and effective biodegradable food packaging biofilms, contributing to the advancement of sustainable packaging materials.

Preparation of transparent and flexible regenerated kenaf CNF composite films with curcumin-metal complex for food packaging applications

Cellulose nanofibers (CNF) derived from kenaf plant were combined with curcumin (Cur)-metal complexes to produce regenerated composite films. Cur was used to synthesize homoleptic Cur-metal complexes with diamagnetic Zn(II) and paramagnetic Cu(II) metal ions. Cur-Zn(II) complex and Cur-Cu(II) complex were synthesized under the same reaction conditions to check the synergistic effect of engaging the diketone electrons of Cur with strong coordination bonds with two different metal ions. The synthesized Cur-metal complexes were used as fillers to produce CNF composite films for biodegradable food packaging film. Results showed that the Cur-Zn(II) complex-loaded CNF composite films exhibit higher antioxidant activity than other films whereas Cur-Cu(II) complex-loaded CNF composite films showed prominent antibacterial activity against foodborne pathogenic bacteria such as Listera monocytogenes and Escherichia coli. It is due to the coordination of the diketone electron of Cur with diamagnetic and paramagnetic metal ions that influenced the antioxidant and antibacterial properties of Cur. Overall, this study proved that it was possible to use Cur in the form of Cur-Zn(II) complex as an antioxidant filler and Cur-Cu(II) complex as an antibacterial filler for active food packaging applications.

Gamma irradiation-induced crosslinking and enhanced functionality of fish gelatin-agar edible films

Fish gelatin-agar edible films have potential for sustainable food packaging, but their limitations particularly water sensitivity require improvement. In this research, the effects of radiation from gamma rays at rates ranging from 0 to 40 kGy on the films' mechanical characteristics, microstructure, color, opacity, and water resistance were examined. Overall, gamma irradiation at doses of up to 30 kGy substantially improved the water resistance of the gelatin-agar film, as demonstrated by decreased water solubility, water absorption, and film vapor permeability. This could be due to crosslinking within the biopolymer network. However, at doses of 40 kGy, potential chain scission in the film's polymeric structure might occur, which counteracts further improvement and consequently starts degrading its water resistance. Similarly, the improvement of film's tensile strength and modulus of elasticity peaked at an optimal dose of 30 kGy, and then decreased at higher doses, while the film's elongation at break remained unaffected. FTIR and SEM analysis supported changes in functional group and structural morphology in these observations. Although irradiation caused some yellowing, an optimal dose range (at around 20–30 kGy) was identified to achieve improved functionality without degrading film integrity. These findings highlight the potential of gamma irradiation as a viable technique for modifying fish gelatin-agar films for enhanced performance in food packaging applications.