Antifungal packaging of sorbate and benzoate incorporated biodegradable films for fresh noodles

Sugar/sugar alcohol with glycerol as co-plasticizers for high-content starch/PBAT blown films: from fine structure to physicochemical properties

BACKGROUND

Glycerol is a well-known plasticizer for starch-based materials, but it easily migrates during starch retrogradation, thereby deteriorating the films' properties. We hypothesized that the performance of high-content starch/poly(butylene adipate-co-terephthalate) (PBAT) films could be enhanced by using sugar/sugar alcohol (glucose, sucrose and sorbitol) as natural, green and edible co-plasticizers with glycerol.

RESULTS

The employment of co-plasticizers reduced the melt fluidity of the blends, established intermolecular hydrogen bonds with starch and resulted in a brittle film structure. The presence of sucrose contributed to the formation of more B-type starch crystals. Glucose and sucrose promoted the conversion of bound water to entrapped water, while sorbitol contributed to more bound water. The co-plasticizers enhanced films' thermal stability, moisture permeability (from 3.61 to 3.72 × 10-11 g m m-2 s-1 Pa-1), and oxygen barrier (from 12.84 to 8.74 × 10-13 cm3 cm cm-2 s-1 Pa-1). Glucose/glycerol co-plasticized film had the maximum tensile strength (10.12 MPa), and sucrose/glycerol co-plasticized film showed the highest Young's modulus (380.31 MPa).

CONCLUSION

Sorbitol with linear structure and the lowest melting point exhibited a plasticizing capacity similar to glycerol. The molecular structure (linear or cyclic), hydroxyl group proportion and melting point of the sugar/sugar alcohol were the key factors to regulate the fine structure and properties of starch/PBAT films. © 2024 Society of Chemical Industry.

Melt-Processed Polybutylene-Succinate Biocomposites with Chitosan: Development and Characterization of Rheological, Thermal, Mechanical and Antimicrobial Properties

The current research is devoted to the development and characterization of green antimicrobial polymer biocomposites for food packaging applications. The biocomposites were developed by melt compounding on the basis of two different succinate polymer matrices with varying chain stiffness-polybutylene succinate (PBS) or its copolymer with 20 mol.% of polybutylene adipate (PBSA). Fungi chitosan oligosaccharide (C98) and crustacean chitosan (C95) were used as antimicrobial additives. The rheological properties of the developed biocomposites were determined to clear out the most suitable temperature for melt processing. In addition, mechanical, thermal, barrier and antimicrobial properties of the developed biocomposites were determined. The results of the investigation revealed that PBSA composites with 7 wt% and 10 wt% of the C98 additive were more suitable for the development of green packaging films because of their higher ultimate elongation values, better damping properties as well as their superior anti-microbial behavior. However, due to the lower thermal stability of the C98 additive as well as PBSA, the melt processing temperatures of the composites desirably should not exceed 120 °C. Additionally, by considering decreased moisture vapor barrier properties, it is recommended to perform further modifications of the PBSA-C98 composites through an addition of a nanoclay additive due to its excellent barrier properties and thermal stability.

Starch as a smart, cheap, and green gatekeeper for the controlled release of propyl gallate from antioxidant biodegradable packaging films

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.

Potential of phytic acid in synergy with sodium chloride as a natural-borne preservative to inactivate Escherichia coli O157:H7 and inhibit natural microflora in fresh noodles at room temperature

The increase in consumer demand and the high cost of maintaining a cold chain during distribution emphasize the need for preservative technology to ensure the microbiological quality of fresh noodles with a moisture content of 32-40%. However, few studies have been conducted to increase the storage stability of fresh noodles by using a preservative with a significant inhibitory effect against microorganisms and/or minimizing the use of synthetic antimicrobial agents. This study aimed to propose a synergistic natural-borne antimicrobial that could interact with NaCl, an essential component of noodles, for extended preservation of fresh noodles at room temperature. NaCl (0-1.6% (w/w) based on the total weight of the noodle dough) and phytic acid (0-1.0% (v/w)) were applied to fresh noodles. The bactericidal effect on Escherichia coli O157:H7 and the inhibitory effect on the indigenous microflora were assessed within 21 days at 30 °C. After cooking fresh noodles, physicochemical/textural and sensory characteristics (whiteness, pH, water activity; hardness, adhesiveness, springiness, chewiness; appearance, odor, overall acceptance) were further evaluated as objective and subjective quality parameters. In fresh noodles preserved with 0.6% phytic acid and 1.6% NaCl, the E. coli O157:H7 population was eliminated below the detection limit (>5.8 log reduction; P < 0.05) within 4 days of storage. This preservative significantly inhibited (P < 0.05) the mesophilic bacterial and total yeast/mold counts naturally present in fresh noodles for 12 days, while the largest antimicrobial activity was observed in noodles supplemented with 1.0% phytic acid combined with 1.0-1.6% NaCl. Although the objective parameters were significantly affected by the preservatives, analysis of the subjective parameters demonstrated that all samples were slightly or moderately favored by the panelists (P > 0.05). Considering the normal range of objective parameters for fresh noodles, the optimal preservative was determined to be 0.6% phytic acid and 1.6% NaCl. This study suggests the potential use of phytic acid as a natural-borne preservative that combines with NaCl in fresh noodles and exerts a synergistic effect. The developed method is expected to be applicable to extending the shelf life of other grain-based foods containing NaCl as an essential ingredient.

A biodegradable pH-response packaging film with blueberry extract: Blown-extrusion fabrication, multifunctional activity, and kinetic investigation

This work proposed a novel strategy for manufacturing biodegradable pH-response packaging. Briefly, to minimize the amount and thermal processing times of blueberry extract (BE), ethanol-dissolved BE (≤ 3‰ w/w) was sprayed onto the starch/poly(butylene adipate-co-terephthalate) (PBAT) pellets before extrusion blowing. BE was well-integrated into the matrix, forming uniformly colored films. The films with BE exhibited superior mechanical (7.85 MPa of strength, 606.53% of elongation) and enhanced barrier capabilities against ultraviolet light, moisture, and gas. Additionally, they exhibited good antioxidant capacity (68.69%), antibacterial activity (72.40%), and maintained color stability. The film with 3‰ w/w BE presented excellent color responsiveness (ΔE⁎ ≥ 15) in the alkaline range, and successfully monitored the spoilage of shrimp. The pigments in the film had the maximum migration degree (≥ 70%) and rate in 50% ethanol simulation, following a first-order kinetic behavior dominated by Fickian diffusion. Findings supported the application of this strategy in the fabrication of starch/PBAT/BE films for pH-response intelligent packaging.

Effect of polydimethylsiloxane on the structure and barrier properties of starch/PBAT composite films

This study aimed to investigate the effects of polydimethylsiloxane (PDMS) with a low surface energy on the structure and physicochemical properties of starch/poly (butylene adipate-co-terephthalate) (PBAT) blown films. The film's appearance was not significantly changed after the addition of PDMS. Compared with the films without PDMS, the films with PDMS displayed a smoother surface. A 2% w/w PDMS addition resulted in the maximum mechanical properties (8.10 MPa of strength, 211.00% of modulus) and surface hydrophobicity (87°) of the films. By contrast, the film with 3% w/w PDMS showed the lowest light transmittance, water vapor (2.73 × 10-11 g·cm·cm2·s-1·Pa-1) and oxygen permeability (9.73 × 10-13·cm3·cm·cm-2·s-1·Pa-1), owing to the improved tightness of the matrix, which increased the zigzag path for molecules to pass through. Films with higher PDMS contents effectively extended the shelf life of packaged bananas and shiitake mushrooms, benefiting from the outstanding and appropriate barrier properties, according to principal component analysis results. Findings supported that high-content starch/PBAT films containing PDMS had potential in the preservation of fresh agricultural products.

An Overview of Advanced Antimicrobial Food Packaging: Emphasizing Antimicrobial Agents and Polymer-Based Films

The food industry is increasingly focused on maintaining the quality and safety of food products as consumers are becoming more health conscious and seeking fresh, minimally processed foods. However, deterioration and spoilage caused by foodborne pathogens continue to pose significant challenges, leading to decreased shelf life and quality. To overcome this issue, the food industry and researchers are exploring new approaches to prevent microbial growth in food, while preserving its nutritional value and safety. Active packaging, including antimicrobial packaging, has gained considerable attention among current food packaging methods owing to the wide range of materials used, application methods, and their ability to protect various food products. Both direct and indirect methods can be used to improve food safety and quality by incorporating antimicrobial compounds into the food packaging materials. This comprehensive review focuses on natural and synthetic antimicrobial substances and polymer-based films, and their mechanisms and applications in packaging systems. The properties of these materials are compared, and the persistent challenges in the field of active packaging are emphasized. Specifically, there is a need to achieve the controlled release of antimicrobial agents and develop active packaging materials that possess the necessary mechanical and barrier properties, as well as other characteristics essential for ensuring food protection and safety, particularly bio-based packaging materials.

Biopolymer-based packaging films/edible coatings functionalized with ε-polylysine: New options for food preservation

In light of the commendable advantages inherent in natural polymers such as biocompatibility, biodegradability, and cost-effectiveness, researchers are actively engaged in the development of biopolymer-based biodegradable food packaging films (BFPF). However, a notable limitation is that most biopolymers lack intrinsic antimicrobial activity, thereby restricting their efficacy in food preservation. To address this challenge, various active substances with antibacterial properties have been explored as additives to BFPF. Among these, ε-polylysine has garnered significant attention in BFPF applications owing to its outstanding antibacterial properties. This study provides a brief overview of the synthesis method and chemical properties of ε-polylysine, and comprehensively examines its impact as an additive on the properties of BFPF derived from diverse biopolymers, including polysaccharides, proteins, aliphatic polyesters, etc. Furthermore, the practical applications of various BFPF functionalized with ε-polylysine in different food preservation scenarios are summarized. The findings underscore that ε-polylysine, functioning as an antibacterial agent, not only directly enhances the antimicrobial activity of BFPF but also serves as a cross-linking agent, interacting with biopolymer molecules to influence the physical and mechanical properties of BFPF, thereby enhancing their efficacy in food preservation.

Progress in the Preparation and Application of Breathable Membranes

Breathable membranes with micropores enable the transfer of gas molecules while blocking liquids and solids, and have a wide range of applications in medical, industrial, environmental, and energy fields. Breathability is highly influenced by the nature of a material, pore size, and pore structure. Preparation methods and the incorporation of functional materials are responsible for the variety of physical properties and applications of breathable membranes. In this review, the preparation methods of breathable membranes, including blown film extrusion, cast film extrusion, phase separation, and electrospinning, are discussed. According to the antibacterial, hydrophobic, thermal insulation, conductive, and adsorption properties, the application of breathable membranes in the fields of electronics, medicine, textiles, packaging, energy, and the environment are summarized. Perspectives on the development trends and challenges of breathable membranes are discussed.

Unveiling the Future of Meat Packaging: Functional Biodegradable Packaging Preserving Meat Quality and Safety

Meat quality and shelf life are important parameters affecting consumer perception and safety. Several factors contribute to the deterioration and spoilage of meat products, including microbial growth, chemical reactions in the food's constituents, protein denaturation, lipid oxidation, and discoloration. This study reviewed the development of functional packaging biomaterials that interact with food and the environment to improve food's sensory properties and consumer safety. Bioactive packaging incorporates additive compounds such as essential oils, natural extracts, and chemical substances to produce composite polymers and polymer blends. The findings showed that the incorporation of additive compounds enhanced the packaging's functionality and improved the compatibility of the polymer-polymer matrices and that between the polymers and active compounds. Food preservatives are alternative substances for food packaging that prevent food spoilage and preserve quality. The safety of food contact materials, especially the flavor/odor contamination from the packaging to the food and the mass transfer from the food to the packaging, was also assessed. Flavor is a key factor in consumer purchasing decisions and also determines the quality and safety of meat products. Novel functional packaging can be used to preserve the quality and safety of packaged meat products.

Development of cinnamon essential oil-loaded PBAT/thermoplastic starch active packaging films with different release behavior and antimicrobial activity

The poly (butylene adipate-co-terephthalate)/thermoplastic starch (PBAT/TPS) active packaging films containing cinnamon essential oil (CEO) were fabricated by melting blending and extrusion casting method. The effects of TPS content (0 %, 10 %, 20 %, 30 %, 40 % and 50 %) on the properties of the films and their application in largemouth bass preservation were studied. As TPS content increased from 0 % to 50 %, the water vapor permeability increased from 7.923 × 10-13 (g•cm/(cm2•s•Pa)) to 23.967 × 10-13 (g•cm/(cm2•s•Pa)), the oxygen permeability decreased from 8.642 × 10-11 (cm3•m/(m2•s•Pa)) to 3.644 × 10-11 (cm3•m/(m2•s•Pa)), the retention of CEO in the films increased. The release rate of CEO from the films into food simulant (10 % ethanol) accelerated with increasing TPS. The films exhibited different antibacterial activity against E. coli, S. aureus, and S. putrefaciens. It was closely related with the release behavior of the CEO. The films containing CEO could efficiently inhibit the decomposition of protein and the growth of microorganisms in largemouth bass. It showed that the higher TPS in the films, the better inhibitory effect. This study provided a new idea for developing PBAT/TPS active films with different release behavior of active agents and different antibacterial activity for food packaging.

Starch/poly (butylene adipate-co-terephthalate) blown films contained the quaternary ammonium salts with different N-alkyl chain lengths as antimicrobials

Antimicrobial biodegradable packaging is in high demand as a one-two punch against microbiological and plastic hazards. Two quaternary ammonium salts (QAS) with different N-alkyl chain lengths were used for starch/poly (butylene adipate-co-terephthalate) (PBAT) blown antimicrobial films. Dioctadecyl dimethyl ammonium chloride (D1821) contributed to a homogeneous film morphology at 5% w/w level, while micro-pores occurred with didodecyl dimethyl ammonium chloride (D1221). Increasing QAS content weakened hydrogen bonding interactions. D1821 promoted the formation of intercalated structure of nano-clays, and improved the strength, thermal stability, barrier, and surface hydrophobicity of the films. Conversely, adding D1221 decreased the mechanical properties, and significantly enhanced the surface hydrophilicity. The films with 3% and 5% w/w D1221 obviously inhibited the growth of both Staphylococcus aureus and Escherichia coli, while those with D1821 cannot show clear zone against the Gram-negative. 5% w/w D1221-loaded film delayed the growth of microorganisms in beef, of which the total viable count was 5.75 lg CFU/g after 21-day chilling storage. Findings supported that QAS had the potential for manufacturing starch/PBAT antimicrobial packaging, but the release kinetics and cytotoxicity still need to be systematically explored before application.

Effect of active antimicrobial films on quality parameters and shelf-life of fresh yufka dough

This research aimed to develop polypropylene (PP) antimicrobial films loaded with different concentrations of sorbic acid (SA) for packaging of fresh yufka dough. PP-SA at 6% showed improved mechanical, UV absorption, and moisture barrier properties. Also, the obtained films exhibited in vitro antibacterial and anti-mold properties. Moisture content and aw of packaged dough with different types of active films were not significantly changed upon storage period. Extended storage of dough layered with PP-SA films at concentrations 0-4% for 45 days led to significant decrease of pH from 5.75 in fresh dough to 5.05 in control (p < 0.05). Color attributes including yellowness and whiteness indices of dough were declined and increased, respectively as function of prolonged storage and increase in the concentration of SA. The growth of aerobic psychrotrophic bacteria and filamentous fungi were significantly retarded in yufka dough packaged with PP-SA6% film compared to that packaged with control as well as PP-SA2-4% films. Direct addition of SA into the bulk of dough was not effective in preservation of dough against the growth of bacteria and fungi. Application of antimicrobial preservatives in the composition of PP films could be beneficial in preserving fresh foods such as bakery products against spoilage microorganisms.

Starch/poly(butylene adipate-co-terephthalate) blown antimicrobial films based on ε-polylysine hydrochloride and different nanomontmorillonites

With increasing awareness on environmental protection and food safety, the development of biodegradable antimicrobial packaging materials has been paid growing emphasis. In this work, starch/poly(butylene adipate-co-terephthalate)/ε-polylysine hydrochloride films were prepared by extrusion blowing, and five commercial organically modified nanomontmorillonites (OMMT, including DK1, DK2, DK3, DK4, and DK5) were used as reinforcing agents. Intercalated structures were formed in the nanocomposite films, especially for those with DK3 and DK4 owing to their higher hydrophobicity and larger interlayer spacing. Adding OMMT weakened hydrogen bonds and the gelatinization/plasticization degree of starch. Morphology analysis revealed that the agglomeration of OMMT occurred in the films, but the film containing DK3 still showed a relatively homogeneous microstructure. Loading OMMT enhanced the strength, deformation resistance, thermal stability, surface hydrophobicity, but decreased barrier properties and water sensitivity of the films. Antimicrobial activity showed that the OMMT and ε-polylysine hydrochloride possessed a synergistic effect against Staphylococcus aureus and Escherichia coli. The maximum inhibition rate was observed in that with DK4, approaching 100 %. Findings supported the application of commercial OMMT in manufacturing biodegradable antimicrobial blown films.

Development and application of fruit and vegetable based green films with natural bio-actives in meat and dairy products: a review

In recent years, foodborne outbreaks and food plastic waste accumulation in the environment have impelled a hunt for new, sustainable, novel and innovatory food packaging interventions to face microbial contamination, food quality and safety. Pollution caused from wastes generated by agricultural activities is one of chief rising concerns of the environmentalists across the globe. A solution to this problem is effective and economic valorization of residues from agriculture sector. It would ensure that the by-products/residues from one activity act as ingredients/raw materials for another industry. An example is fruit and vegetable waste based green films for food packaging. Edible packaging is a well-researched area of science where numerous biomaterials have been already explored. Along with dynamic barrier properties, these biofilms often exhibit antioxidant and antimicrobial properties as function of the bioactive additives (e.g. essential oils) often incorporated in them. Additionally, these films are made competent by use of recent technologies (e.g. encapsulation, nano-emulsions, radio-sensors) to ensure high end performance and meet the principles of sustainability. Livestock products such as meat, poultry and dairy products are highly perishable and depend largely upon the mercy of packaging materials to enhance their shelf life. In this review, all the above-mentioned aspects are thoroughly covered with a view to project fruit and vegetable based green films (FVBGFs) as a potential and viable packaging material for livestock products, along with a discussion on role of bio-additives, technological interventions, properties and potential applications of FVBGFs in livestock products. © 2023 Society of Chemical Industry.

Antibacterial Effects of Theaflavins against Staphylococcus aureus and Salmonella paratyphi B: Role of Environmental Factors and Food Matrices

This study aimed to investigate the effects of different environmental factors (temperature, pH, and NaCl) and food matrices (skimmed milk powder, lecithin, and sucrose) on the antibacterial activity of theaflavins (TFs) against Staphylococcus aureus (S. aureus) and Salmonella paratyphi B (S. paratyphi B). TFs showed a larger diameter of inhibition zone (DIZ, 12.58 ± 0.09 mm-16.36 ± 0.12 mm) value against S. aureus than that of S. paratyphi B (12.42 ± 0.43 mm-15.81 ± 0.24 mm) at the same concentration (2-10 mg/mL). When temperatures were 25-121 °C, the DIZ of TFs against both S. aureus and S. paratyphi B was not significantly different. As pH increased from 2 to 10, their DIZ values decreased significantly from 16.78 ± 0.23 mm to 13.43 ± 0.08 mm and 15.63 ± 0.42 mm to 12.18 ± 0.14 mm, respectively. Their DIZ values increased slightly as the NaCl concentration increased from 0.2 mol/L to 0.8 mol/L, while their DIZ values decreased significantly for skimmed milk powder concentrations in the range of 20-120 g/L. Regarding the concentrations of lecithin and sucrose were 2-12 g/L and 10-60 g/L, their DIZ values showed no significant change against S. paratyphi B, but an increased trend for S. aureus. Under the above different environmental factors and food matrices, TFs maintained excellent antibacterial activity against S. aureus and S. paratyphi B, providing a theoretical guidance for applying TFs as novel antibacterial additives in the food industry.

Application of a biodegradable poly(butylene adipate-co-terephthalate) membrane for phenol pervaporation recovery

In the field of membrane separation, the environmental concerns caused by spent membranes are becoming increasingly serious, which contradicts the concept of sustainable development. Based on this, a biodegradable poly(butylene adipate-co-terephthalate) (PBAT) membrane was used for the first time in the pervaporation separation of phenol, a high boiling point organic compound (HBOC). By using the PBAT membrane, outstanding separation efficiency was achieved, and environmental pollution and disposal issues were also avoided. The separation process and mechanism of the PBAT membrane were systematically studied through the experiment together with molecular dynamics (MD) simulation. The swelling experiment and intermolecular interaction energy calculation demonstrated that the PBAT membrane had a strong affinity for phenol. Further simulation concluded that higher phenol concentration increased the number of hydrogen bonds so that the membrane was more greatly swollen. Meanwhile, the simulations on the adsorption, diffusion and permeation predicted that the PBAT membrane had excellent separation performance for phenol. Besides MD simulation, the influences of feed concentration and temperature on pervaporation performance were also investigated by experiment. The results showed that the flux of each component increased with the feed concentration. This phenomenon was attributed to the preferential adsorption of phenol by the PBAT membrane, which resulted in large free volumes and cavities within the membrane, accelerating the diffusion of molecules. In addition, it was found that the optimal operating temperature was 333 K with the best separation performance. This study confirms that the biodegradable PBAT membrane is valuable for the recovery of high boiling point organic compounds (HBOCs) such as phenol.

A Review on Biopolymer-Based Biodegradable Film for Food Packaging: Trends over the Last Decade and Future Research

In recent years, much attention has been paid to the use of biopolymers as food packaging materials due to their important characteristics and properties. These include non-toxicity, ease of availability, biocompatibility, and biodegradability, indicating their potential as an alternative to conventional plastic packaging that has long been under environmental scrutiny. Given the current focus on sustainable development, it is imperative to develop studies on biopolymers as eco-friendly and sustainable food packaging materials. Therefore, the aim of this review is to explore trends and characteristics of biopolymer-based biodegradable films for food packaging, analyze the contribution of various journals and cooperation between countries, highlight the most influential authors and articles, and provide an overview of the social, environmental, and economic aspects of biodegradable films for food packaging. To achieve this goal, a bibliometric analysis and systematic review based on the PRISMA method were conducted. Relevant articles were carefully selected from the Scopus database. A bibliometric analysis was also conducted to discuss holistically, comprehensively, and objectively biodegradable films for food packaging. An increasing interest was found in this study, especially in the last 3 years with Brazil and China leading the number of papers on biodegradable films for food packaging, which were responsible for 20.4% and 12.5% of the published papers, respectively. The results of the keyword analysis based on the period revealed that the addition of bioactive compounds into packaging films is very promising because it can increase the quality and safety of packaged food. These results reveal that biodegradable films demonstrate a positive and promising trend as food packaging materials that are environmentally friendly and promote sustainability.

Development of chitosan/konjac glucomannan/tragacanth gum tri-layer food packaging films incorporated with tannic acid and ε-polylysine based on mussel-inspired strategy

Constructing biodegradable food packaging with good mechanics, gas barrier and antibacterial properties to maintain food quality is still challenge. In this work, mussel-inspired bio-interface emerged as a tool for constructing functional multilayer films. Konjac glucomannan (KGM) and tragacanth gum (TG) with physical entangled network are introduced in the core layer. Cationic polypeptide ε-polylysine (ε-PLL) and chitosan (CS) producing cationic-π interaction with adjacent aromatic residues in tannic acid (TA) are introduced in the two-sided outer layer. The triple-layer film mimics the mussel adhesive bio-interface, where cationic residues in outer layers interact with negatively charged TG in the core layer. Furthermore, a series of physical tests showed excellent performance of triple-layer film with great mechanical properties (tensile strength (TS): 21.4 MPa, elongation at break (EAB): 7.9 %), UV-shielding (almost 0 % UV transmittance), thermal stability, water, and oxygen barrier (oxygen permeability (OP): 1.14 × 10^-3 g/m s Pa and water vapor permeability (WVP): 2.15 g mm/m² day kPa). In addition, the triple-layer film demonstrated advanced degradability, antimicrobial functions, and presented good moisture-proof performance for crackers, which can be potentially applied as dry food packaging.

Property improvement of a thermoplastic starch/poly(butylene adipate-co-terephthalate) blown film by the addition of sodium nitrite

Recently, global awareness of the adverse environmental impacts of single-use plastics has risen due to their nonbiodegradability and likelihood of ending up in the ocean. Thermoplastic starch (TPS) is an alternative material employed for manufacturing single-use products because of its high biodegradability, nontoxicity, and low cost. However, TPS is moisture sensitive and has poor mechanical properties and processability. Blending TPS with biodegradable polyesters, including poly(butylene adipate-co-terephthalate) (PBAT), can expand its practical applications. This research aims to improve the performance of TPS/PBAT blends by adding sodium nitrite, a food additive, and considering its effect on the morphological characteristics and properties of TPS/PBAT blends. TPS/PBAT/sodium nitrite (TPS/PBAT/N) blends with a TPS:PBAT weight ratio of 40:60 and sodium nitrite concentrations of 0.5, 1, 1.5, and 2 wt% were prepared by extrusion and then blown into films. The acids generated from the sodium nitrite during extrusion led to the molecular weight reduction of starch and PBAT polymers, causing the increased melt flow ability of the TPS/PBAT/N blends. The incorporation of sodium nitrite improved the blends' homogeneity and the compatibility between the TPS and PBAT phases, resulting in the increased tensile strength, extensibility, impact strength, and oxygen barrier properties of the TPS/PBAT blend film.

Biocompatible and Biodegradable 3D Printing from Bioplastics: A Review

There has been a lot of interest in developing and producing biodegradable polymers to address the current environmental problem caused by the continued usage of synthetic polymers derived from petroleum products. Bioplastics have been identified as a possible alternative to the use of conventional plastics since they are biodegradable and/or derived from renewable resources. Additive manufacturing, also referred to as 3D printing, is a field of growing interest and can contribute towards a sustainable and circular economy. The manufacturing technology also provides a wide material selection with design flexibility increasing its usage in the manufacture of parts from bioplastics. With this material flexibility, efforts have been directed towards developing 3D printing filaments from bioplastics such as Poly (lactic acid) to substitute the common fossil- based conventional plastic filaments such as Acrylonitrile butadiene styrene. Plant biomass is now utilized in the development of biocomposite materials. A lot of literature presents work done toward improving the biodegradability of printing filaments. However, additive manufacture of biocomposites from plant biomass is faced with printing challenges such as warping, low agglomeration between layers and poor mechanical properties of the printed parts. The aim of this paper is to review the technology of 3D printing using bioplastics, study the materials that have been utilized in this technology and how challenges of working with biocomposites in additive manufacture have been addressed.

Enhanced compatibility and functionality of thermoplastic cassava starch blended PBAT blown films with erythorbate and nitrite

Improved miscibility between thermoplastic starch (TPS) and polybutylene adipate-co-terephthalate (PBAT) enhances processability and properties of TPS-based biodegradable plastic packaging. This research investigated compatibility and functionality of TPS/PBAT (50/50) blends with sodium nitrite and sodium erythorbate (1-5%) via blown film extrusion. Film morphology and mechanical and barrier properties were investigated. Sodium nitrite and sodium erythorbate improved processing efficiency of TPS, modified film flexibility and enhanced physical and chemical compatibility between TPS and PBAT matrices via hydrolysis, confirmed by ¹H NMR and ATR-FTIR analyses. These chemical reactions also affected thermal and phase transition behaviors. Increased starch granule dispersion caused smoother microstructure, resulting in higher oxygen barrier. Sodium nitrite and sodium erythorbate functionalized TPS/PBAT films reduced discoloration of packaged cured meat during storage at 4 °C for 9 days. These compounds provided extra functionality and improved compatibility between TPS and PBAT biodegradable plastic blends for novel and sustainable food packaging.

Preparation, characterization, and antibacterial effect of bio-based modified starch films

There are several problems with common starch films, including strong water absorption and poor mechanical properties. To create a better starch film, octenyl succinate cassava starch ester (OSCS) was first blended with chitosan and nano ZnO to prepare an OSCS/CS/ZnO film. Then, the film was supplemented with different concentrations of ε-PL as a bacteriostatic agent to prepare a film that would resist bacterial invasion. The mechanical properties, barrier properties, optical properties, and color of the modified starch antibacterial films were investigated, and finally the antibacterial properties and cytotoxicity were tested. The results demonstrated that the modified starch antibacterial film had good mechanical properties, improved surface hydrophobicity, and had a UV-blocking effect. The modified starch antibacterial film with ε-PL of 8% had stable and long-lasting antibacterial properties, stable release, and good cytocompatibility. An active packaging material was successfully prepared using ε-PL and had a strong preservative effect on food.

Effects of adding methods and modification types of cellulose on the physicochemical properties of starch/PBAT blown films

This study revealed the relationship between cellulose types/adding methods and film properties, in which sodium carboxymethyl cellulose (CMC), hydroxypropyl methyl cellulose (HPMC), and microcrystalline cellulose (MCC) were added into starch/PBAT blown films in powder, aqueous solution, and emulsion forms, respectively. Cellulose interacted with starch networks via hydrogen bonds, and those added in emulsion form made more homogeneous film morphologies. MCC emulsion enhanced the film strength (40%) and modulus (149%) to the greatest extent, while comprehensively, HPMC emulsion possessed better reinforcement effects on the films, which increased mechanical properties (31% ~ 100%), moisture barrier (20%), oxygen barrier (93%), surface hydrophobicity (20%), as well as water resistance (12% ~ 76%). Findings supported the application of cellulose in high-throughput biodegradable films, and the high-content starch/PBAT blown films reinforced by HPMC emulsion had great potential in commercial packaging fields.

Polysaccharide-Based Biodegradable Films: An Alternative in Food Packaging

Packaging can mitigate the physical, chemical, and microbiological phenomena that affects food products’ quality and acceptability. However, the use of conventional packaging from non-renewable fossil sources generates environmental damage caused by the accumulation of non-biodegradable waste. Biodegradable films emerge as alternative biomaterials which are ecologically sustainable and offer protection and increase food product shelf life. This review describes the role of biodegradable films as packaging material and their importance regarding food quality. The study emphasizes polysaccharide-based biodegradable films and their use in foods with different requirements and the advances and future challenges for developing intelligent biodegradable films. In addition, the study explores the importance of the selection of the type of polysaccharide and its combination with other polymers for the generation of biodegradable films with functional characteristics. It also discusses additives that cause interactions between components and improve the mechanical and barrier properties of biodegradable films. Finally, this compilation of scientific works shows that biodegradable films are an alternative to protecting perishable foods, and studying and understanding them helps bring them closer to replacing commercial synthetic packaging.

Preparation of bio-based modified starch film and analysis of preservation mechanism for sweet cherry

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Preparation of modified bio-based starch film by casting method.

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Mechanism characterization of modified bio-based starch film.

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Modified bio-based starch film has preservation effect on sweet cherry.

This study aimed to synthesize packaging films using bioactive ingredients. The composite film was prepared by blending octenyl succinate cassava starch ester (OSCS) with chitosan (CS) nano-ZnO and then adding ε-polylysine (ε-PL). The study also explored the effect of different concentrations of ε-PL on OSCS/CS/ZnO films. Fourier infrared spectroscopyand fluorescence microscopy revealed that the composite film was formed by both hydrogen bonding and a Schiff base reaction. The diffraction peaks of the original materials in X-ray diffraction disappeared after film formation, indicating good miscibility between the materials. Scanning electron microscope showed that the density of its structure increased with increasing the ε-PL content. The thermogravimetric analysis showed that the addition of ε-PL improved the thermal stability of the composite film to some extent. When used in cherry preservation, the bio-based modified starch film effectively reduced cherry decay, stem dryness, and weight loss, maintained surface color, and increased the soluble solid content.

Antibacterial, Antifungal and Antiviral Polymeric Food Packaging in Post-COVID-19 Era

Consumers are now more concerned about food safety and hygiene following the COVID-19 pandemic. Antimicrobial packaging has attracted increased interest by reducing contamination of food surfaces to deliver quality and safe food while maintaining shelf life. Active packaging materials to reduce contamination or inhibit viral activity in packaged foods and on packaging surfaces are mostly prepared using solvent casting, but very few materials demonstrate antiviral activity on foods of animal origin, which are important in the human diet. Incorporation of silver nanoparticles, essential oils and natural plant extracts as antimicrobial agents in/on polymeric matrices provides improved antifungal, antibacterial and antiviral properties. This paper reviews recent developments in antifungal, antibacterial and antiviral packaging incorporating natural or synthetic compounds using preparation methods including extrusion, solvent casting and surface modification treatment for surface coating and their applications in several foods (i.e., bakery products, fruits and vegetables, meat and meat products, fish and seafood and milk and dairy foods). Findings showed that antimicrobial material as films, coated films, coating and pouches exhibited efficient antimicrobial activity in vitro but lower activity in real food systems. Antimicrobial activity depends on (i) polar or non-polar food components, (ii) interactions between antimicrobial compounds and the polymer materials and (iii) interactions between environmental conditions and active films (i.e., relative humidity, oxygen and water vapor permeability and temperature) that impact the migration or diffusion of active compounds in foods. Knowledge gained from the plethora of existing studies on antimicrobial polymers can be effectively utilized to develop multifunctional antimicrobial materials that can protect food products and packaging surfaces from SARS-CoV-2 contamination.

Athermal Concentration of Blueberry Juice by Forward Osmosis: Food Additives as Draw Solution

This study is to evaluate the athermal forward osmosis (FO) concentration process of blueberry juice using food additives as a draw solution (DS). The effects of food additives, including citric acid, sodium benzoate, and potassium sorbate, on the concentration processes are studied, and their effects on the products and membranes are compared. Results show that all these three food additives can be alternative DSs in concentration, among which citric acid shows the best performance. The total anthocyanin content (TAC) of blueberry juice concentrated by citric acid, sodium benzoate, and potassium sorbate were 752.56 ± 29.04, 716.10 ± 30.80, and 735.31 ± 24.92 mg·L^-1, respectively, increased by 25.5%, 17.8%, and 19.9%. Meanwhile, the total phenolic content (TPC) increased by 21.0%, 10.6%, and 16.6%, respectively. Citric acid, sodium benzoate, and potassium sorbate all might reverse into the concentrated juice in amounts of 3.083 ± 0.477, 1.497 ± 0.008, and 0.869 ± 0.003 g/kg, respectively. These reversed food additives can make the TPC and TAC in juice steadier during its concentration and storage. Accordingly, food additives can be an excellent choice for DSs in the FO concentration process of juices, not only improving the concentration efficiency but also increasing the stability of blueberry juice.

Antimicrobial, sealable and biodegradable packaging to maintain the quality of shredded carrots and pineapple juice during storage

Increasing consumer demand for foods with high nutritional quality, prolonged shelf life and low environmental impact of the package, is driving innovation towards the development of new packaging. Multifunctional food packaging films, biodegradable, heat-sealable and antimicrobial, were developed. A PLA coating layer incorporating either sodium benzoate, potassium sorbate, or a combination of them was deposited onto a poly(lactic) acid/poly(butylene adipate-co-terephthalate) substrate film. The effectiveness of the developed systems to preserve the quality of foods was tested in shelf-life experiments performed on shredded carrots and pineapple juice, selected as model processed raw foods. The best performance was observed for the active film containing potassium sorbate: microbial populations increased less rapidly and were 0.7-1.8 log CFU/g lower at the end of storage period in this film than in control packs. Of the two model foods, the pineapple juice was better preserved: after 7 days in active packaging, color change and microbial counts of juice were below that of control, observed after one day and after 3 days of storage respectively. Moreover, the incorporation of the active phases did not significantly affect the mechanical, barrier and optical properties of the films, opening new ways to prolong shelf-life of minimally processed foods.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s13197-022-05435-y.

Nano Coating of Aloe-Gel Incorporation Additives to Maintain the Quality of Freshly Cut Fruits

The edible coating is an environmentally friendly technology that is applied to fresh-cut fruit products. One of the natural ingredients that are potentially applicable is aloe-gel because it contains several functional components. The main advantage of aloe-coating is that additives can be incorporated into the polymer matrix to enhance its properties. Additives tend to improve the safety, nutritional, and sensory attributes of fresh fruits, but in some cases, aloe-coating does not work. Furthermore, particle size determines the effectiveness of the process on fresh-cut fruits. Aloe-gel nano-coating can be used to overcome the difficulty of adhesion on the surface of fresh-cut fruits. However, quality criteria for fresh cut fruit coated with aloe-gel nano-coating must be strictly defined. The fruit to be processed must be of minimal quality so that discoloration, loss of firmness, spoilage ratio, and fruit weight loss can be minimized. This study aims to discuss the use of nano-coating aloe-gel incorporated with additional ingredients to maintain the quality of fresh-cut fruits. It also examined the recent advances in preparation, extraction, stabilization, and application methods in fresh fruits.

Blown film extrusion of PBAT/TPS/ZnO nanocomposites for shelf-life extension of meat packaging

Biodegradable polymers typically have inferior barrier properties compared to petroleum-based nonbiodegradable plastic. The addition of zinc oxide nanoparticles may enhance the functional properties of biodegradable packaging and extends the shelf life of packaged foods. Polybutylene adipate-co-terephthalate (PBAT) and thermoplastic starch (TPS) blended ZnO (1-5%) nanocomposite films were developed via blown extrusion for functional active meat packaging. The nanocomposite film morphology showed agglomeration of the nanoparticles, causing poor mechanical properties. Nanovoids formed at the interface between the polymer and nanoparticles, increasing permeability. Dispersion of ZnO nanofillers modified CO and C-O ester bonding in PBAT and increased hydrogen bonding with TPS. The interaction between ZnO and polymers increased the dispersion and reduced the agglomeration of nanoparticles. The highest ZnO content at 5% resulted in a stronger interaction between ZnO and TPS due to increased amorphous starch content, which improved homogeneous dispersion within the matrices, reducing nanoparticle size. The ZnO nanocomposite films reduced lipid oxidation and delayed microbial growth, resulting in a lower total viable count, lactic acid bacteria and yeast and mold in packaged pork meat. Higher ZnO concentrations from 3% showed microbial inhibitory effects. The growth of microorganisms was controlled by residual oxygen, morphology of the films and nanoparticle characteristics. The nanocomposite films effectively extended the shelf life by more than 3 days under refrigerated conditions.

Application of innovative packaging technologies to manage fungi and mycotoxin contamination in agricultural products: Current status, challenges, and perspectives

The consumer demand for safe, "healthy," and premium foods, preferably with an extended shelf-life; demand for easy packaging; and choice for more sustainable food packaging have contributed to the development of novel packaging technologies. The application of adequate packaging materials has recently become a major post-harvest challenge concerning the control of fungi and mycotoxin. This review will describe the current antifungal packaging technology involved to prevent the contamination of fungi and mycotoxin, along with the characteristics and mechanism of action in food products. Antifungal packaging has incredible potential in the food packaging sector. The most suitable approach for the safe storage of agricultural produce for farmers is the hermetic packaging technology, which maintains quality while providing a good barrier against fungi and mycotoxin. Furthermore, active antifungal packaging is a viable method for incorporating antifungal agents against pathogenic fungi. Essential oils and organic acid have received more scientific attention due to their increased efficacy against mold growth. Polypeptides, chitosan, and natamycin incorporated in active packaging significantly reduced fungi. Even though nanotechnological advancements in antifungal packaging are promising, safety and regulation issues remain significant concerns.

Preparation of an Antimicrobial and Antioxidant Bio-Polymer Film and Its Application as Glazing Shell for Postharvest Quality of Fresh-Cut Apple

The aim of this work is to glazing a modified bio-polymer shell as substitute of peel to keep the postharvest quality of fresh-cut fruits. In this study, chitosan as backbone of the shell was modified by addition of the functional extracts obtained from Zanthoxylum, in which 12 kinds of main identified bio-active components consisted of over 55% of the total extracts. The introduction of the extracts improved physic and mechanical properties of the shell, and endowed it with significant antimicrobial and antioxidant activity. Accordingly, the modified chitosan was used as the substitute of peel to preserve fresh-cut apples. Results exhibited that such treatments obviously delayed the decline process of overall postharvest quality of the preserved apple samples throughout all the storage period, represented by the variations in physical, chemical, and microbial properties of the apple samples were significantly inhibited. The overall observations revealed promising potential of the bio-polymer shell in food application.

Evaluation of Modified Atmosphere Packaging in Combination with Active Packaging to Increase Shelf Life of High-in Beta-Glucan Gluten Free Cake

Modified atmosphere packaging and active packaging were combined to prolong the shelf life and quality of the clean label, gluten-free (GF), yeast-leavened cakes enriched in oat fiber preparation. Star anise, cinnamon bark, and clove essential oils were used as emitters of active substances. The following concentrations of gases were chosen: 0% CO₂/100%/N₂ (MAP₁), 60% CO₂/40% N₂ (MAP₂), and approx. 78% N₂/21% O₂/0.04% CO₂ (ATM). Microbiological and physicochemical analyses were conducted. GF cakes were stored for 14 days (analysis in 0, 7, and 14 days). The results showed a decrease in moisture content and lightness of crumb and an increase in hardness. EOs significantly (p ≤ 0.05) slowed down the growth of microorganisms regardless of the type of gas mixture. However, the best bacteriostatic effect was in MAP₂. The content of beta-glucan did not change throughout the storage time. Generally, the best results were obtained with the combination of MAP and active packaging—60% of CO₂ and 40% of N₂—where cinnamon or clove essential oils were used.

Recent Advancements in Smart Biogenic Packaging: Reshaping the Future of the Food Packaging Industry

Due to their complete non-biodegradability, current food packages have resulted in major environmental issues. Today’s smart consumer is looking for alternatives that are environmentally friendly, durable, recyclable, and naturally rather than synthetically derived. It is a well-established fact that complete replacement with environmentally friendly packaging materials is unattainable, and bio-based plastics should be the future of the food packaging industry. Natural biopolymers and nanotechnological interventions allow the creation of new, high-performance, light-weight, and environmentally friendly composite materials, which can replace non-biodegradable plastic packaging materials. This review summarizes the recent advancements in smart biogenic packaging, focusing on the shift from conventional to natural packaging, properties of various biogenic packaging materials, and the amalgamation of technologies, such as nanotechnology and encapsulation; to develop active and intelligent biogenic systems, such as the use of biosensors in food packaging. Lastly, challenges and opportunities in biogenic packaging are described, for their application in sustainable food packing systems.

Characterization of Sodium Alginate-Locust Bean Gum Films Reinforced with Daphnetin Emulsions for the Development of Active Packaging

In this study, we characterized an active film made of sodium alginate (SA)—locust bean gum (LBG) containing daphnetin-based film. Physicochemical characteristics, as well as antioxidant and antibacterial properties, were investigated. The results showed that the addition of a low concentration of daphnetin increased the flexibility of SA–LBG cling film, leading to an improvement in elongation at break and tensile strength. As the daphnetin content increased, solubility, brightness and transparency of the cling film decreased, and the moisture permeability increased. The antioxidant capacity and antibacterial activity of films with daphnetin were improved compared to those of the basal film. In addition, the cling film formed by adsorption had higher bacterial (Shewanella putrefaciens and Pseudomonas fluorescens) inhibition and antioxidant activity rates than direct film formation. The results indicate that the combination of daphnetin in SA–LBG film provides an active film with antioxidant and antibacterial properties, with potential for the development of food-grade packaging material.

Effects of nisin and EDTA on morphology and properties of thermoplastic starch and PBAT biodegradable films for meat packaging

Biodegradable active packaging was produced by compounding nisin (3, 6 and 9%) and nisin-ethylenediaminetetraacetic acid (EDTA) (3 and 6%) mixtures with poly(butylene adipate terephthalate) and thermoplastic starch blends (PBAT/TPS) by blown-film extrusion. Nisin and EDTA interacted with polymers, involving CO stretching of ester bonds and increased compatibility. This plasticized the films and modified the crystallinity, surface roughness and thermal relaxation behavior. Barrier properties were improved due to modified hydrophilic-hydrophobic properties, compact structures and crystallites that restricted vapor and oxygen permeation. PBAT/TPS films containing EDTA and nisin effectively inhibited lipid degradation in pork tissues corresponding with stabilizing the CO ester bond of triacylglycerol. Microbial growth was also inhibited, particularly in EDTA-containing films up to 1.4 log. Inactivation of microorganisms stabilized redness and delayed meat discoloration, preserving the quality of packaged pork. Interaction between nisin, EDTA and polymers modified the morphology and film properties and functionalized biodegradable food packaging to inactivate microorganisms.

Applications of Inorganic Nanoparticles in Food Packaging: A Comprehensive Review

Nanoparticles (NPs) have acquired significance in technological breakthroughs due to their unique properties, such as size, shape, chemical composition, physiochemical stability, crystal structure, and larger surface area. There is a huge demand for packaging materials that can keep food fresher for extended periods of time. The incorporation of nanoscale fillers in the polymer matrix would assists in the alleviation of packaging material challenges while also improving functional qualities. Increased barrier properties, thermal properties like melting point and glass transition temperatures, and changed functionalities like surface wettability and hydrophobicity are all features of these polymers containing nanocomposites. Inorganic nanoparticles also have the potential to reduce the growth of bacteria within the packaging. By incorporating nano-sized components into biopolymer-based packaging materials, waste material generated during the packaging process may be reduced. The different inorganic nanoparticles such as titanium oxide, zinc oxide, copper oxide, silver, and gold are the most preferred inorganic nanoparticles used in food packaging. Food systems can benefit from using these packaging materials and improve physicochemical and functional properties. The compatibility of inorganic nanoparticles and their various forms with different polymers make them excellent components for package fortification. This review article describes the various aspects of developing and applying inorganic nanoparticles in food packaging. This study provides diverse uses of metals and metal oxides nanoparticles in food packaging films for the development of improved packaging films that can extend the shelf life of food products. These packaging solutions containing nanoparticles would effectively preserve, protect, and maintain the quality of the food material.