The application of novel insect proteins as future food resources in the food field has attracted more and more attention. In this study, a biodegradable antibacterial food packaging material with beneficial mechanical properties was developed using Tenebrio molitor larvae protein (TMP), chitosan (CS) and propolis ethanol extract (PEE) as raw materials. PEE was uniformly dispersed in the film matrix and the composite films showed excellent homogeneity and compatibility. There are strong intermolecular hydrogen bond interactions between CS, TMP, and PEE in the films, which exhibit the structure characteristics of amorphous materials. Compared with CS/TMP film, the addition of 3 % PEE significantly enhanced the elongation at break (34.23 %), water vapor barrier property (22.94 %), thermal stability (45.84 %), surface hydrophobicity (20.25 %), and biodegradability of the composite film. The composite film has strong antioxidant and antimicrobial properties, which were enhanced with the increase of PEE content. These biodegradable films offer an eco-friendly end-of-life option when buried in soil. Composite films can effectively delay the spoilage of strawberries and extend the shelf life of strawberries. Biodegradable active packaging film developed with insect protein and chitosan can be used as a substitute for petroleum-based packaging materials, and has broad application prospects in the field of fruits preservation.

The demand for UV-protective and biodegradable packaging materials has been increasing with greater awareness about environmental sustainability and human safety. In this work, the effect of incorporating riceberry phenolic extract (RPE) as well as combined RPE and green synthesized biogenic nano‑silver (RPE-NS, into Tara gum/PVA (TP)-based matrix was evaluated on the physical, mechanical, functional, biocompatible and biodegradable attributes of the resultant composite films. Integration of RPE (2 wt%) and RPE-NS (0.8 wt%) resulted in nanocomposite (TP/RPE-NS) film with improved physical properties relative to the plain TP and TP/RPE films. The TP/RPE-NS film displayed a compact structure and homogenous distribution of the nano‑silver. Increased molecular interactions, crystallinity and thickness was also observed for the nanocomposite film. Compared to plain TP film, TP/RPE-NS film exhibited improved water vapor barrier properties and surface hydrophobicity due to the extract and nanoparticles. The tensile strength and elongation-at-break of TP/RPE-NS were markedly higher (41.76 MPa and 37.40 %) compared to that of plain TP film (36.07 MPa and 20.80 %). Whereas TP/RPE film provided good UV protection (UPF value of 31.85) compared to the minimal protection by TP film (UPF value of 2.72), combination of RPE/RPE-NS ensured that TP/RPE-NS availed an excellent UV-barrier performance (UPF value of 61.09). Furthermore, TP/RPE-NS film exhibited significant antioxidant activity relative to TP film. Besides, all TP-based films were found to be compatible with rat erythrocytes and biodegradable. Taken together, these findings indicate that TP/RPE-NS holds good potential for the development of UV-protective and biodegradable packaging material.

This research was undertaken to assess the effect of tragacanth gum-chitin nanofiber (TG-CNF) film containing free (CEO) or encapsulated cumin essential oil (CNE) combined with oxygen absorber (OA) packaging on the shelf-life of ready-to-cook (RTC) turkey breast burgers during chilled storage. The experimental groups were OA and TG-CNF as single treatments, TG-CNF + CEO, TG-CNF + CNE, and TG-CNF + OA as binary treatments, TG-CNF + CEO + OA and TG-CNF + CNE + OA as ternary treatments, and control. The samples were stored at 3°C for 20 days and analyzed for microbial, physicochemical, and sensory attributes. Binary treatments, when compared to single treatments, and ternary treatments, when compared to binary treatments, exhibited enhanced effectiveness in managing microbial growth, hindering physicochemical alterations, and decelerating sensory alterations. At day 20, TG-CNF + CNE + OA group was identified as the most effective group in inhibiting the growth of total mesophilic bacteria (TMB), total psychrophilic bacteria (TSB), and coliforms (final counts were 4.8, 4.16, and ≤1 log CFU/g, respectively), and TG-CNF + CNE + OA and TG-CNF + CEO + OA groups were known as the most effective groups in inhibiting lactic acid bacteria (LAB) (final counts were 4.71 and 5.15 log CFU/g, respectively). Furthermore, the TG-CNF + CNE + OA treatment proved to be the most effective group in reducing the total volatile nitrogen (TVN) (final level was 19.2 mg N/100 g) and thiobarbituric acid reactive substances (TBARS) (final level was 0.119 mg malondialdehyde (MDA)/kg). TG-CNF + CNE + OA and TG-CNF + CEO + OA were the most efficient groups to delay the increasing rate of cooking loss (final values were 23.3% and 24.6%) and pH (final values were 7.01 and 6.99). The sample\'s shelf-life was 4 days in control and TG-CNF, 8 days in OA and TG-CNF + OA, 12 days in TG-CNF + CEO, 16 days in TG-CNF + CNE and TG-CNF + CEO + OA, and at least 20 days in TG-CNF + CNE + OA. As a result, the incorporation of TG-CNF + CNE alongside OA packaging emerges as a highly effective active packaging method for preserving RTC turkey breast burgers during chilled storage.

In this work, the modification of poly(butylene adipate-co-terephthalate) (PBAT) was combined with the development of active packaging films. PBAT, starch, plasticizer, and tea polyphenols (TP) were compounded and extrusion-blown into thermoplastic starch (TPS)/PBAT-TP active films. Effects of TPS contents on physicochemical properties, functional activities, biodegradability, and release kinetics of PBAT-based active films were explored. Starch interacted strongly with TP through hydrogen bonding and induced the formation of heterogeneous structures in the films. With the increase in TPS contents, surface hydrophilicity and water vapor permeability of the films increased, while mechanical properties decreased. Blending starch with PBAT greatly accelerated degradation behavior of the films, and the T30P70-TP film achieved complete degradation after 180 days. As TPS contents increased, swelling degree of the films increased and TP release were improved accordingly, resulting in significantly enhanced antioxidant and antimicrobial activities. This work demonstrated that filling starch into PBAT-based active films could achieve different antioxidant and antimicrobial activities of the films by regulating film swelling and release behavior.

The effect of plasticizers, namely glycerol, sorbitol, and citric acid, on the structural and mechanical properties of biodegradable films obtained from xanthan gum (XG) and starch was studied. The plasticizing effect of glycerol, sorbitol, and citric acid on XG-starch films is justified by the destruction of intermolecular contacts between starch and XG macromolecules and the redistribution of hydrogen bonds in the system as a result of the hydrotropic action of plasticizer molecules. The use of glycerol proved to be the most effective for regulating the deformation of films, while the use of sorbitol to preserve strength. The dependence of the film roughness on the type and concentration of plasticizers was characterized. The smallest values of protrusions on the surface of XG-starch films were found in the presence of sorbitol. Considering the effect of the concentration of plasticizers on the stickiness of the surface of XG-starch films and their structural and mechanical properties, 1.5 % concentration of glycerol, sorbitol and citric acid was determined as optimal.

Polyvinyl alcohol (PVA)-bacterial succinoglycan (SG) biodegradable films were developed through a solvent-casting method. Effects of the PVA/SG ratio on the thickness, transmittance, water holding capacity, and structural and mechanical properties were investigated by various analytical methods. All the prepared films were transparent and uniform, and XRD and FTIR analyses confirmed that PVA was successfully incorporated into SG. The films also showed excellent UV-blocking ability: up to close to 80% with increasing SG concentration. The formation of effective intermolecular interactions between these polymers was evidenced by their high tensile strength and moisture transport capacity. By measuring the biodegradation rate, it was confirmed that films with high SG content showed the fastest biodegradation rate over 5 days. These results confirm that PVA/SG films are eco-friendly, with both excellent biodegradability and effective UV-blocking ability, suggesting the possibility of industrial applications as a packaging material in various fields in the future.

Petroleum-based packaging materials are nondegradable and unsustainable and thus are harmful to the environment. Renewable packaging films prepared from bio-based raw materials are promising alternatives to petroleum-based packaging materials. In this study, colorless and transparent bio-based films were successfully cast using a solution containing a mixture of arabinogalactan (AG) and poly (vinyl alcohol) (PVA). Vanillin was incorporated into the mixture to endow the films with UV-shielding, antioxidant, and antibacterial properties. The morphological, physical, antioxidant, and antibacterial properties of the blend films were then characterized. At an AG:PVA weight ratio of 1:3, and the vanillin content was 0.15 %, the tensile strength of the AG/PVA/Vanillin (APV) films reached ~28 MPa, while their elongation at break reached ~475 %. The addition of vanillin significantly affected the antioxidant and antibacterial properties of the blend films, which exhibited superb UV barrier capacity. The APV films exhibited extremely low oxygen transmittance, delaying the onset of mold/rot in strawberries and reducing their weight loss. Because of the heat sealability of the blend films, they can be used for encapsulating various substances, such as concentrated laundry liquid. Moreover, the blend films were recyclable and biodegradable. Thus, these films have great potential for applications that require sustainable packaging.

Oxidative rancidity of food products and massive consumption of plastic packaging have put the necessity in manufacturing novel antioxidant biodegradable packaging films. A comprehensive investigation was conducted on starch/poly(butylene adipate-co-terephthalate) (PBAT) antioxidant blown films, in which starch acted as a gatekeeper for the controlled release of propyl gallate (PG). PG was well integrated into the matrices and bound to starch molecules by hydrogen bonding. All films showed strong anti-ultraviolet performance, and higher oxygen barrier than the traditional polyethylene film. Increasing starch proportions promoted the swelling of films and the release of PG, thereby causing higher antioxidant activity at the same contact time to free radical solutions. Similar polarity made PG prone to partition and rapid migration into the food simulants with higher ethanol concentration and the high-fat-content peanut butter. The film with 20:80 w/w starch/PBAT proportion and 3% w/w PG content effectively suppressed the oxidation of peanut butter within 300-day storage. Findings demonstrated this strategy for manufacturing starch/PBAT antioxidant films as a long-term active packaging in food industry.

Biodegradable plastic films have emerged as a substitute for conventional plastic films. Nevertheless, responses of plant-associated microbiomes to the application of biodegradable film mulching at field scale have received little attention. A field experiment was conducted to assess the influence of different film mulching treatments on various microbial attributes and nitrogen (N) cycling functional genes in bulk and rhizosphere soils. Biodegradable film mulching raised the bacterial Shannon index in bulk soils but not in rhizosphere soils. Biodegradable film mulching has led to an increase in the complexity and connectivity of microbial networks, as well as an enhancement in the positive association among microorganisms owing to raised soil nutrients and increased crop biomass. In biodegradable film-treated soils, both bacterial and fungal communities were primarily influenced by stochastic processes associated with dispersal limitation. Moreover, conventional plastic film mulching increased denitrification, anammox, N fixation, and dissimilatory nitrate-reduction (DNRA) gene abundance in bulk soils. In rhizosphere soils, biodegradable film mulching reduced nitrification, denitrification, anammox, N fixation, and DNRA gene abundance. Furthermore, keystone genera (e.g., Nitrosospira, Truepera, Adhaeribacter, Opitutus, and Fusarium) were affected by edaphic variables, contributing to decreased N-cycling gene abundance in biodegradable film-treated soils. Collectively, biodegradable film mulching transformed soil microbiome assembly and functional adaptation, and soil nutrient availability and plant biomass were the critical factors influencing the microbial community. These findings present a novel perspective on the diverse impacts of biodegradable and conventional film mulching on soil microbiome and N-cycling processes.

This study presents a novel packaging film based on whey protein isolate/κ-carrageenan (WC) with red grape pomace anthocyanins (RGA) to investigate its impact on some qualitative attributes of emergency food bars (EFBs) for 6 months at 38°C. Increasing the RGA dose in WC films from 5% (WCA5) to 10% (WCA10) reduced hydrogen bonding between polymers and polymer homogeneity in the matrix according to FTIR and SEM. Tensile strength slightly declined in WCA5 from 7.47 ± 0.26 to 6.97 ± 0.12, while elongation increased from 27.74 ± 1.36 to 32.36 ± 1.25% compared to WC film. The maximum weight loss temperature (TM) increased by incorporating 5 wt% RGA from 182.95°C to 244.36°C, whereas TM declined to 187.19°C in WCA10 film. WVP and OTR slightly changed in WCA5 (from 7.83 ± 0.07 and 2.57 ± 0.18 to 8.41 ± 0.03 g H2O.m/m2.Pa.s × 10-9 and 1.79 ± 0.32 cm3 O2/m2.d.bar, respectively), but significantly impaired in WCA10 compared to WC film. WCA5 and WCA10 films had high AA%, 68.77%, and 79.21%, respectively. WCA10 film presented great antimetrical properties against Staphylococcus aureus with an inhibition zone of 6.00 mm. The light transmission of RGA-contained films in the UV spectrum was below 10%. The WCA5 film effectively restrained moisture loss and hardness increment until the end of the storage period, which were 14.33% and 28.76%, respectively, compared to day 0. Antioxidant films provided acceptable resistance against oxidation to EBF treatment. Sensory panels scored WCA5 and WCA10 higher in overall acceptance with 5.64 and 5.40 values, respectively, while complaining about the hardness of OPP treatment. The results of this investigation demonstrated that incorporating RGA, preferably 5 wt%, into WC-based film effectively improved the qualitative properties of EFB during the 6-month shelf life. This film might be a promising alternative for packaging light and oxygen-sensitive food products.