This study focused on developing a carboxymethyl cellulose (CMC)-based packaging film with excellent water resistance for preserving high-moisture foods. To this end, we incorporated exfoliated graphitic carbon nitride (g-C3N4) into a CMC matrix and cross-linked it with citric acid (CA) and carbon dots (CD) to create a multifunctional, nacre-mimicking double-cross-linked film (CMC/g-C3N4/CA/CD). The CMC/g-C3N4/CA/CD film showed a 58.8% increase in tensile strength and a 40.0% reduction in water vapor transmission rate compared to the control CMC film. Additionally, its moisture resistance improved significantly, and it kept its shape intact even after being immersed in water for 100 h. Moreover, the composite film demonstrated excellent functional properties, including a strong antioxidant effect that completely removed ABTS radicals and a potent antibacterial effect that fully inhibited the growth of S. enterica and L. monocytogenes. When used for blueberry packaging, this film effectively inhibits microbial contamination, maintains pH and firmness, reduces weight loss, and extends shelf life by up to 16 days. This nacre-mimicking biopolymer-based packaging material, with its high moisture resistance and physical strength, offers a promising alternative to petroleum-based plastic packaging.

Fresh fruits and vegetables are essential to everyday diets, and growing global attention is focused on their quality and safety. Protecting freshness and ensuring safety after harvest is therefore a key requirement for building a sustainable and environmentally friendly supply of fruits and vegetables. In response, substantial research has focused on advanced materials that support postharvest quality management and safety monitoring. Two-dimensional nanomaterials (2D-NMs) have emerged as particularly promising materials for these applications because of their layered structures, large specific surface areas, and adjustable physicochemical characteristics. This review discusses the main ways 2D-NMs can be used for postharvest fruits and vegetables quality control, covering gas barrier regulation, antimicrobial performance, and controlled release behavior in packaging systems. The study also presents 2D-NM-based strategies for detecting pesticides, as well as sensor platforms for postharvest quality monitoring of fruits and vegetables. Overall, it summarizes the practical use of 2D-NMs in postharvest quality control and safety monitoring, with a central focus on their incorporation as functional additives in packaging films.

Poly(vinyl alcohol)/carrageenan (PVA/Car)-based multifunctional composite films were developed by incorporating metal glycerate complexes such as cobalt copper glycerate (CoCuGly), cobalt nickel glycerate (CoNiGly), and cobalt iron glycerate (CoFeGly). These metal glycerate complexes exhibited excellent compatibility with the polymer matrix, resulting in dense, flexible, and mechanically reinforced films. Structural and morphological characteristics were analyzed using high-resolution transmission electron microscopy (HR-TEM), field emission scanning electron microscopy (FE-SEM), Fourier-transform infrared (FT-IR), and X-ray photoelectron spectroscopy (XPS). The tensile strength of the PVA/Car-based films improved significantly from 61.03 MPa to 75.34, 79.67, and 65.53 MPa for the incorporating metal glycerate complex composite films. The composite films also showed enhanced antibacterial activity against Gram-negative bacteria (Escherichia coli and Salmonella enterica) and Gram-positive bacteria (Listeria monocytogenes and Staphylococcus aureus). The composite films exhibit excellent antioxidant activity, as confirmed by ABTS radical scavenging assay. Furthermore, the incorporation of the metal glycerate complex significantly enhanced UV-blocking ability. Cytotoxicity evaluation using L929 fibroblast cells (MTT assay) showed that metal glycerate complex-incorporated composite films demonstrated excellent cytocompatibility. Overall, the developed multifunctional films possess machinal strength, antibacterial activity, UV-blocking, antioxidant capacity, and biocompatibility, making them highly promising for active packaging of perishable foods.

Nanotechnology offers innovative strategies for developing advanced active and intelligent food packaging systems to address these multifaceted issues. This review explores the critical role of nanomaterials (NMs) in food packaging innovation, focusing on real-time sensing, mechanical interactions and security applications. This review provides mechanistic insights into nanomaterial-analyte interactions, including surface chemistry, charge transfer phenomena, plasmonic effects and signal transduction pathways. Applications in food security and anti-counterfeiting are also discussed, with particular emphasis on luminescent tags, nanophotonic inks, and blockchain-integrated nanosensors. We critically assess sustainability aspects-such as environmental impact, portability, toxicity, and biodegradability-alongside regulatory considerations, and examine challenges related to material design, data integration, consumer acceptance and the use of AI and machine learning for predictive quality monitoring. The report concludes by proposing future directions toward a fully sustainable, intelligent, and safe food system that harnesses nanotechnology to improve food safety, reduce waste, and ensure supply chain transparency.

The necessity for creative food preservation techniques has grown as customer demand for high-quality, safe poultry products rises. A potential strategy that incorporates sensors, indications, and responsive materials to track product quality in real time is intelligent packaging. The safety, shelf life, and sensory quality of chicken, one of the most popular and perishable meats, can be jeopardized by microbiological infection, chemical deterioration, and enzymatic spoiling. This article highlights the shortcomings of traditional preservation systems while offering a thorough overview of chicken spoilage, including its kinds, underlying mechanisms, and the intrinsic and extrinsic factors impacting degradation. Sustainable intelligent packaging systems that use bio-based sensors and pH-responsive indicators for quick and accurate spoiling detection are given special attention. Natural colorimetric compounds, such as anthocyanins, curcumin, and other plant-derived pigments, whose pH-dependent colour transitions allow visual monitoring of freshness while also contributing antioxidant and antimicrobial properties, are increasingly incorporated into biodegradable matrices like films, hydrogels, and nanofibers. The design factors, performance traits, and real-world uses of these systems for chicken preservation are also covered in this review. Intelligent packaging has many benefits, such as real-time freshness monitoring, decreased food waste, and improved customer safety, despite ongoing difficulties with cost, scalability, and material stability. Overall, this study highlights recent developments in pH-responsive intelligent packaging systems for chicken and describes how they might be used to create efficient and sustainable meat preservation methods.

Efficacy of individual and combined preservation technologies involving soursop leaf extract (SLE), pulsed electric field (PEF), vacuum impregnation (VI), modified atmosphere packaging (MAP; 60% CO2/30% N2/10% Ar) and cold plasma (CP) on microbiological, chemical and sensory properties were analyzed, and the nextgeneration sequencing (NGS) of microbiota was performed on Pacific white shrimp during 21 days storage at 4 degrees C. The PEF-SLE1-VI-MAP1-CP treatment effectively delayed spoilage, maintaining the total viable count (TVC) of shrimp below 6 log CFU/g until day 21. NGS revealed a shift from spoilage-associated taxa (Enterobacteriaceae, Vagococcus) to less detrimental lactic acid bacteria (Weissella), which might be associated with different effects of MAP1 gas composition and the reactive species produced by CP towards varying bacteria. Chemically, the indole, trimethyl amine (TMA) and total volatile base (TVB) levels in treated samples remained below the spoilage thresholds of 25 mu g/100 g, 5 mg/100 g, and 30 mg/100 g, respectively, while control samples exceeded the limits by day 9. PEF-SLE1-VI-MAP1-CP sample retained higher acceptability (6.0) at day 21, compared to the control (4.2) at day 9. Strong correlations (R2 >= 0.95) were observed between the tested pairs including TVC and psychrotrophic bacteria count (PBC); PBC and Pseudomonas; Pseudomonas and Shewanella; Shewanella and H2Sproducing bacteria; indole and pH; indole and TMA; and pH and TMA. The synergistic effect of PEF-SLE1-VIMAP1-CP inhibited key spoilage bacteria and preserved shrimp 12 days longer than the control's 9 days. These findings emphasize the potential of combined SLE and nonthermal processes for the preservation of shrimp and other seafoods.

Intelligent bilayer films based on bioplastics (PLA/PBAT, PB) and biopolymers (Gelatin/Acacia gum, GA) developed through a sequential wet casting method with the inclusion of crude anthocyanin (AC) and carbon dots (CDs) from Bengal currant fruit and the obtained films were subjected for characterization. In general, GA film was more transparent than PB film. Active film developed with the inclusion of 3% CDs (PB/GA/CD-3%) exhibited the higher Young's Modulus (922 MPa), tensile strength (21 MPa) with lesser elasticity (31%) and water vapor permeability (0.5-1.0 & times; 10(-12) g.m.m(-2).s(-1).Pa-1) (P < 0.05). Nevertheless, no variance in thickness was recorded for films prepared with CDs at different levels (P > 0.05). Color and transparency of active films varied, depending on the amounts of CDs added (P < 0.05). However, UV-blocking competence and thermal resistance of active films were enhanced, when compared to control film (PB/GA). Functional and secondary structure of films were varied based on materials used for the film formation. The different layers of PB and GA were clearly distinguished by SEM micrographs. The bilayer films incorporated with CDs exhibited the higher antioxidant and antimicrobial abilities than their control counterpart (P < 0.05). The quality of black tip shark meat packed in pouches prepared from different films was investigated. Throughout the storage period of 15 days, active pouches prepared with PB/GA/CD-3% preserved the shark slices and extended their shelf life when compared to the sample without any film or packed with polyethylene pouch, as witnessed by retardation of deterioration indices and the loss in quality was ensured by the changes in the tag made of PB/GA-AC. Thus, the developed packaging system including the quality tag containing AC from Bengal currant and the active pouches added with CDs efficiently performed their role as spoilage indicator and extended the shelf life of shark slices, respectively.

A biodegradable and antibacterial absorbent pad was developed from kombucha-fermented bacterial cellulose (BC) and functionalized with carbon dots (CDs) made from Thymus vulgaris flowers. The developed BC@CD pad demonstrated efficient liquid absorption and strong antibacterial activity against foodborne pathogens such as Escherichia coli, Listeria monocytogenes, and Salmonella enterica. Adding CDs to the BC surface provided excellent functional properties, including strong antioxidant performance (ABTS radical scavenging rate 100%), high moisture absorption (5830.9%), excellent moisture retention (51.5 g/g), and very low solubility (4.3%), which helped maintain chicken quality during refrigerated storage and extended its shelf life. During storage, BC@CD pads effectively inhibited lipid oxidation while controlling the appearance, pH, and microbial growth of chicken, extending its shelf life by up to 12 days compared to the control group (which exceeded oxidation levels after 8 days). Overall, this study offers a promising, eco-friendly approach to developing sustainable, multifunctional absorbent pads that improve food preservation without relying on non-degradable plastics.

Color is a primary attribute determining consumer acceptance of premium-quality tuna. Discoloration is commonly considered as the loss of freshness and eating quality, leading to food waste. This study investigated color and quality changes in longtail tuna slices during 48 h of simulated retail display and evaluated the efficacy of epigallocatechin gallate–ascorbic acid (EA) combined with nitrogen- or argon-rich modified atmosphere packaging (NO or AO) in restoring pre-discolored tuna slices (2DS) during 4 days of refrigerated storage. The simulated retail display caused a quick loss of redness (a* value and a*/b*), an increase in metmyoglobin, and enhanced oxidation of lipids and proteins, which made the visual quality undesirable. 2DS-EA/AO profoundly restored the redness, reduced metmyoglobin, and suppressed oxidative degradation. Partial recovery and short-term color stabilization were achieved through the combined treatments, which extended acceptability up to three days. Therefore, a synergistic polyphenol-reducing agent-modified atmosphere packaging (MAP) approach could be used to restore discolored sashimi-grade tuna and decrease tuna waste associated with undesirable discoloration.

A dual-crosslinked nanocomposite film inspired by nacre was created by embedding exfoliated layered double hydroxide (E-LDH) into a carboxymethyl cellulose (CMC) matrix, followed by chemical and physical crosslinking with citric acid (CA) and carbon dots (CD). The self-assembled brick-mortar structure, reinforced by covalent ester bonds and secondary hydrogen bonding interactions, formed a dense and continuous hybrid network with excellent interfacial cohesion. As a result, the CMC/E-LDH/CA/CD film exhibited a 52.2% increase in tensile strength, along with reductions of 65.2% and 80.0% in water vapor permeability and oxygen transmittance, respectively, thereby overcoming the limitations of biopolymer-based films. Additionally, the nanocomposite film displayed excellent antioxidant activity (ABTS scavenging rate of 100.0%), UV-blocking properties (UV-A 84.7%, UV-B 97.4%), and antibacterial effects (inhibiting the growth of S. enterica and L. monocytogenes). Furthermore, the film preserved grape firmness for 16 days, minimized weight loss, and suppressed microbial growth, thereby maintaining grape quality. Overall, this biomimetic reinforcement strategy provides a practical method for developing competitive cellulose-based films with both structural strength and active functionalities, serving as an eco-friendly alternative to petroleum-based packaging materials.

This study investigated the effects of cellulose nanofibrils (CNF) and TEMPO-oxidized CNF (T-CNF) on improving the physicochemical properties, stability, and controlled release characteristics of biopolymer (BP)-based oleogels designed for curcumin encapsulation and 3D-printed food applications. Incorporation of CNF and T-CNF to BP-based oleogels (pectin, carboxymethyl cellulose (CMC), alginate, hydroxypropyl methylcellulose (HPMC400), and methylcellulose (MC400)) resulted in a structural change from a disordered network to a highly interconnected fibrous structure, thereby enhancing oil retention. As a result, CNF- and T-CNF-BP-based oleogels exhibited higher elasticity and solid-like properties compared to BP-based oleogels. Depending on the type of biopolymer, the incorporation of T-CNF improved the oil binding capacity from 75-95% to 94-98%, and increased curcumin release from 29-45% to 35-56%. Simulated gastrointestinal digestion, however, revealed that CNF had no significant effect on delayed free fatty acid (FFA) release, while HPMC400 and MC400 had a significant effect. Textural analysis of the 3D-printed oleogels revealed that CNF and T-CNF increased the hardness of BP-based oleogels, contributing to improved structural integrity during printing and subsequent post-processing. This study demonstrates the potential of CNF and T-CNF to enhance the functional performance, improve their structural properties, and expand the practical applications of BP-based oleogels in advanced 3D-printed food systems.

The widespread use of petroleum-based plastics in food packaging has contributed significantly to environmental pollution, while bio-based and biodegradable alternatives still face challenges in meeting performance requirements. Here, multifunctional bilayer films were developed to address these limitations by integrating materials tailored to provide complementary properties. The films consist of a hydrophobic, bio-based, and biodegradable poly(lactic acid)–poly(hydroxyalkanoate) nanocomposite (PLA–PHA NC) as the outer layer and a hydrophilic and biodegradable poly(vinyl alcohol) (PVA)-based composite as the inner layer. In the outer layer, graphene oxide (GO), TEMPO-oxidized cellulose nanofibers (T-CNF), and clove oil as a natural plasticizer were incorporated to enhance mechanical strength and optical and gas barrier properties, providing effective protection against environmental factors. The PLA–PHA NC was surface-modified to accommodate the PVA layer, ensuring strong interfacial adhesion and structural integrity. The PVA layer incorporated red cabbage anthocyanins for pH-responsive color changes and antioxidant activity, along with ZnO and CuO microparticles to impart antibacterial properties. Bilayer films containing 3 wt% CuO or ZnO exhibited balanced mechanical performance, excellent light barrier properties, strong antibacterial and antioxidant activities, and the lowest oxygen permeability. Furthermore, their distinct color changes in response to ammonia and pH variations enabled real-time spoilage detection. Application tests using shrimp as a model perishable food demonstrated the effectiveness of the bilayer films as freshness indicators, as well as their ability to preserve food quality and extend shelf life. These findings highlight the potential of the designed bilayer system as a multifunctional material for advanced food packaging applications.

Transforming agro-waste into carbon dots (CDs) enables sustainable biomass valorization while producing versatile nanomaterials for applications in packaging and food safety. CDs were synthesized using an eco-friendly hydrothermal method from different leaf powders including cashew (C-CDs), jik (J-CDs) and the combined CDs (CJ-CDs), and all CDs were characterized. The resulting CDs yielded nanoscale particle (2.18-2.50 nm) and had remarkable UV-blocking properties. All CDs displayed strong antimicrobial activity against common foodborne bacteria and fungi. Furthermore, CDs had superior radical scavenging activities, in which CJ-CDs exhibited the highest overall antioxidant potential. Notably, CJ-CDs showed enhanced functional performance, suggesting a synergistic effect arising from the combined phytochemical precursors, which likely promoted the improved surface functionality and radical scavenging efficiency. When CJ-CDs were investigated for their potential in preserving precooked baby clam meat (PBCM), treatment with CJ-CDs effectively reduced pH changes, microbial growth and lipid oxidation of PBCM during the refrigerated storage for 12 days. Control sample exceeded the acceptable microbial limit of 6 log CFU/g on day 6, whereas CJ-CD-treated samples (PBCM-CJ-CDs) maintained microbial counts below this limit on day 9, demonstrating a shelf-life extension of longer than 3 days. Overall, the findings indicated that CJ-CDs function as multifunctional natural preservatives with synergistically enhanced antioxidant and antimicrobial properties, offering a sustainable and green alternative to synthetic additives for extending the shelf life of seafood products.

Bilayer (BL) active packaging films were fabricated using solvent-casting method by depositing chitosan-fish gelatin (CS-FG) blend containing turmeric peel-derived carbon dots (Tu(CD)) at 0.75-3 % (w/w, based on CS-FG), onto a polylactic acid (PLA) film. This study elucidated the application of novel Tu(CD) in active food packaging for the first time. The incorporation of Tu(CD) at 3 % (w/w) significantly improved the tensile strength, elongation at break, and water vapor permeability of the films, which rose up to 28.40 %, 116.40 %, and 16.50 %, respectively (p < 0.05). The 3 % Tu(CD) film exhibited exceptional UV-blocking efficacy (97.47 % of UVB and 99 % of UVC), and also demonstrated a dose-dependent antioxidant property with a DPPH radical scavenging activity of 58.98 mmol Trolox equivalent/g film. FTIR spectroscopy confirmed the molecular interactions within the film matrix, indicated by a broadened O-H/N-H stretching peak (3275 cm(-1)) and a shifted C=O stretching peak (1640-1643 cm(-1)). Those chain interactions contributed to the enhanced mechanical properties of the resulting film. SEM images revealed uniform Tu(CD) dispersion in defect-free matrices. BL pouches were prepared with CS-FG containing Tu(CD) as the food-contact layer and PLA as the outer layer. The 3 % Tu(CD) incorporated pouches showed superior preservation efficacy for Asian hard clam edible portion during 15-day refrigerated storage via lowering the lipid oxidation and microbial load (<6 log CFU/g). The release kinetics followed Fickian diffusion (Korsmeyer-Peppas model), enabling sustained antimicrobial action. These findings demonstrated that Tu(CD)-containing BL films could effectively extend the shelf-life of seafood through synergistic antioxidant and antimicrobial mechanisms, offering a sustainable alternative to conventional packaging.

Carbon dots (CD) and hydrochar (HC) derived from nettle were synthesized using a zero-waste synthesis method, and their effectiveness was elucidated as active packaging fillers. Cellulose nanofiber (CNF)-based films were produced by blending CD (CNF/CD) and HC (CNF/HC), resulting in improved preservability of pork sausages. The CNF/CD and CNF/HC films enhanced the UV blocking performance, reducing UV-B transmittance by 91.7% and 83.3% and UV-A transmittance by 85.2% and 58.9%, respectively. The CNF/CD and CNF/HC films strongly inhibited S. enterica, S. aureus, E. coli, and L. monocytogenes, followed by ABTS radical scavenging by 100.0% and 73.2%, respectively. Active packaging studies confirmed that CNF/CD and CNF/HC films prolonged the shelf life of sausages by up to 18 days at 4 °C by delaying lipid oxidation, reducing microbial growth, and maintaining firmness. These findings showed the potential of CD and HC as eco-friendly multifunctional additives in sustainable active packaging for meat preservation.

Precooked blue swimming crab (P-BSC) meat is of high demand but it is perishable with short shelf-life. The effective preservation is still required to maintain the quality and ensure the safety. Therefore, the effects of chitooligosaccharide-catechin conjugate (COSC) (100 and 200 ppm) and high-pressure processing (HPP, 500 MPa for 5 min), individually and in combination, on the microbiological, chemical, and sensory quality of P-BSC lump meat during refrigerated storage (4 +/- 1 degrees C) were investigated. COSC alone slightly delayed microbial growth, while HPP completely inhibited bacterial proliferation up to day 15. The combination of HPP and COSC, particularly HPP + COSC (200 ppm), extended the shelf-life up to 24 days by keeping aerobic plate count below 5 log CFU/g and effectively eliminating Pseudomonas and Vibrio spp. Chemical indicators of spoilage (pH, TVB-N, and TMA-N contents) remained within acceptable limits, and lipid oxidation (PV and TBARS) was significantly retarded. Principal component analysis confirmed strong separation between treated and untreated groups, indicating the efficacy of treatments used. EPA and DHA were not affected after extended storage, while volatile compounds containing spoilage-related acids and esters were reduced. Metagenomic profiling showed that HPP + COSC200 treatment suppressed spoilage and pathogenic taxa (Pseudoalteromonas, Shewanella, and Vibrio), while non-pathogenic Carnobacterium spp. became dominant. Sensory evaluation confirmed no detrimental effects on appearance, texture, odor, or overall acceptability after 24 days. Overall, the combined HPP + COSC200 treatment effectively preserved P-BSC lump meat and extended its shelf-life without compromising the eating quality.

An intelligent/active packaging film based on cellulose nanofibers (CNF) and gelatin (Gel) loaded with carbon dots (CD) functionalized polyaniline (PANI) composites was developed for freshness monitoring and shelf-life extension of fish meat. The loading of PANI@CD on CNF/Gel film showed a strong antioxidant effect, with DPPH and ABTS radical neutralization rates reaching up to 100