Development of Edible Films and Coatings with Antimicrobial Activity

Chitosan-hydroxypropyl methylcellulose and sodium alginate bilayer edible films for chestnut preservation

To address the challenge of preserving fresh chestnuts, chitosan (CS), hydroxypropyl methylcellulose (HPMC), nisin (N), and sodium alginate (SA) were utilized in the preparation of a bilayer edible film named CS-HPMC-N/SA, which was compared to the monolayer films CS-HPMC and CS-HPMC-N. In comparison to the CS-HPMC film, the CS-HPMC-N and CS-HPMC-N/SA films exhibited increased water vapor permeability (WVP), oxygen permeability, and thickness, while transparency, tensile strength (TS), and elongation at break (EAB) were reduced. The bilayer film CS-HPMC-N/SA showed higher WVP, transparency, thickness, and EAB, but lower TS than the monolayer film CS-HPMC-N. The chestnuts coated with CS-HPMC-N/SA showed lower respiratory intensity and decay rate compared to those coated with CS-HPMC and CS-HPMC-N. These results suggested that the bilayer film CS-HPMC-N/SA, containing nisin, has potential as an edible material for preserving fresh chestnuts.

Synergistic antibacterial effect of 405 nm blue light-emitting diodes (LEDs) and gelatin film for inactivation of Escherichia coli O157:H7 and Salmonella Typhimurium on stainless steel and fresh fruit peel

A combined antibacterial effect of 405 nm blue LEDs (BL) and gelatin film (G) was investigated on stainless steel (SUS) and fresh fruit peel for the inactivation of Escherichia coli O157:H7 and Salmonella Typhimurium. On the SUS, the sum of the individual treatments of G for 20 min and BL at 20 J/cm2 was <1 log reduction (log CFU/cm2). In comparison, combination treatment of G and BL (G + BL) at 20 J/cm2 exhibited 2.37 and 3.09 log reduction on E. coli O157:H7 and S. Typhimurium. The G + BL treatment only increased a propidium iodide (PI) uptake, indicating that cell membrane damage occurred. In the G + BL treatment, reactive oxygen species (ROS) scavenging assay confirmed that ROS involved in the bactericidal mechanism. On orange peel, the G + BL treatment at 40 J/cm2 resulted in a 3.05 and 3.17 log reduction on E. coli O157:H7 and S. Typhimurium. In contrast, the individual treatment of G for 40 min led to reductions of 0.63 log CFU/cm2 for E. coli O157:H7 and 0.50 log CFU/cm2 for S. Typhimurium, while the BL treatment at 40 J/cm2 achieved reductions of 0.78 and 0.69 log CFU/cm2, respectively. A synergistic bactericidal effect was similarly observed in the combined treatment groups for both apple and grapefruit peels. In a color and texture analysis, G did not affect hardness, toughness, and visual color of fruit.

Biotoxicity of silver nanoparticles complicated by the co-existence of micro-/nano-plastics

Silver nanoparticles (AgNP) and polystyrene (PS) plastics have been broadly utilized in various field, e.g., food storage, packaging materials, and medical therapies. However, investigation on the potential biotoxicity induced by the co-exposure to AgNP and PS plastics remains understudied. Thus, we performed this study to examine the toxicological profile of the co-exposure to AgNP and PS in mice. Biochemical and microbial characterizations were performed in mice receiving 90-day oral gavage feeding to examine the hepatotoxicity, neurotoxicity, inflammatory responses, gut microbial alterations. It has been found that the presence of plastic particles aggravates the toxicity of silver nanoparticle materials. Regardless of the plastic type and size, energy and choline metabolisms will be altered by the co-exposures. Moreover, microplastics may induce cell damage by modulating fatty acid peroxidation in unison with stimulating inflammatory responses. Due to the smaller size of nanoplastics, they may pass through blood-brain barrier to induce neuronal damage and increase vascular risks. Changes in the microbial functional abundances are sensitive to the microplastics doses. These results support the necessity of reducing the co-exposure between AgNP and multiscale plastics, and advocate further developments of biodegradable package materials to improve food safety.

Strong, tough self-healing multi-functional sodium alginate-based edible composite coating for banana preservation

Edible coatings are a new green technology for preventing the rotting of fruits and extending their shelf lives. However, during storage, respiratory processes can generate large amounts of water, causing the dissolution of these coating. Furthermore, these coating can be mechanically damaged. Therefore, the development of strong, tough, waterproof and self-healing edible coatings is highly desirable. Herein, gluconolactone was slowly oxidized to generate gluconic acid, which was further used to protonate amino groups in wheat gluten (WG), forming strong electrostatic interactions, hydrogen bonds and ester bonds between soy hull nanocellulose (SHNC) and sodium alginate (SA). The introduction of WG and SHNC improved the mechanical strength, hydrophobicity and water retention of the composite film from 28 MPa, 33.2° ± 1.18° and 19.43° ± 0.83° to 60 MPa, 45.13° ± 1.53° and 41.47° ± 0.96°, respectively. Further, the composite film exhibited excellent self-healing, UV resistance and gas-barrier properties. Banana preservation experiments showed that at 25 °C and 50 % RH, the composite coating effectively slowed the mass loss and softening of bananas, delayed the browning of banana peels and ripening of fruit pulp, and extended the shelf life of bananas to 7 days. Therefore, this study provides a new perspective for the preparation of a new, strong, tough, waterproof and self-healing multi-functional edible coating with high potential for the preservation of perishable fruits.

Functional characterization of biodegradable films obtained from whole Paecilomyces variotii biomass

The indiscriminate use of petroleum-based polymers and plastics for single-use food packaging has led to serious environmental problems due the non-biodegradable characteristics. Thus, much attention has been focused on the research of new biobased and biodegradable materials. Yeast and fungal biomass are low-cost and abundant sources of biopolymers with highly promising properties for the development of biodegradable materials. This study aimed to select a preparation method to develop new biodegradable films using the whole biomass of Paecilomyces variotii subjected to successive physical treatments including ultrasonic homogenization (US) and heat treatment. Sterilization process had an important impact on the final filmogenic dispersion and mechanical properties of the films. Longer US treatments produced a reduction in the particle size and the application of an intermediate UT treatment contributed favorably to the breaking of agglomerates allowing the second US treatment to be more effective, achieving an ordered network with a more uniform distribution. Samples that were not filtrated after the sterilization process presented mechanical properties similar to plasticized materials. On the other hand, the filtration process after sterilization eliminated soluble and hydratable compounds, which produced a reduction in the hydration of the films.

Guanidine Derivatives Leverage the Antibacterial Performance of Bio-Based Polyamide PA56 Fibres

Bacterial damage has significantly impacted humanity, prompting the control of harmful microorganisms and infectious diseases. In this study, antibacterial bio-based PA56 fibres were prepared with high-speed spinning using ethylene-methyl acrylate-glycidyl methacrylate terpolymer (EMA) as the compatibiliser and polypentamethylene guanidine sulphate (PPGS) as the antibacterial agent. The effects of PPGS content on the properties of PA56 draw-textured yarns (DTYs) were investigated. The compatibility between PPGS and PA greatly improved with EMA incorporation. Compared with PA56 fibres, the elongation at break of the sample containing 2.0 wt% EMA and PPGS increased by 25.93%. The inhibition rates of the fibres with 1.0 wt% PPGS against Escherichia coli and Staphylococcus aureus reached over 99.99%. Samples were easily coloured with dyes, exhibiting good colour fastness, regardless of the EMA content. However, the antibacterial performances of dyed DTYs decreased to varying degrees. the inhibition rates of samples of 0.5wt% addition of PPGS against E. coli were reduced from 99.99% to 28.50% and 25.36% after dyeing with Acid Blue 80 and Dispersible Blue 2BLN, respectively. The EMA-modified fibres exhibited the best antibacterial activity after dyeing with neutral gray 2BL. These findings are expected to promote the wider use of biobased PA56 in practical applications that require antibacterial performance and to guide the dyeing process of antimicrobial fibres.

Fundamentals of Edible Coatings and Combination with Biocontrol Agents: A Strategy to Improve Postharvest Fruit Preservation

Challenges in global food supply chains include preserving postharvest quality and extending the shelf life of fruits and vegetables. The utilization of edible coatings (ECs) combined with biocontrol agents (BCAs) represents a promising strategy to enhance the postharvest quality and shelf life of these commodities. This review analyzes the most recent developments in EC technologies and their combination with BCAs, highlighting their synergistic effects on postharvest pathogen control and quality maintenance. Various types of ECs, including polysaccharides, proteins, and lipids, are discussed alongside coating fundamentals and the mechanisms through which BCAs contribute to pathogen suppression. The review also highlights the efficacy of these combined approaches in maintaining the physicochemical properties, sensory attributes, and nutritional value of fruits. Key challenges such as regulatory requirements, consumer acceptance, and the scalability of these technologies are addressed. Future research directions are proposed to optimize formulations, improve application techniques, and enhance the overall efficacy of these biocomposite coatings and multifunctional coatings. By synthesizing current knowledge and identifying gaps, this review provides a comprehensive understanding of the potential and limitations of using ECs and BCAs for sustainable postharvest management.

Advances and recent trends in plant-based materials and edible films: a mini-review

Plant-based materials and edible films have emerged as promising alternatives to conventional packaging materials, offering sustainable and environmentally friendly solutions. This mini-review highlights the significance of plant-based materials derived from polysaccharides, proteins, and lipids, showcasing their renewable and biodegradable nature. The properties of edible films, including mechanical strength, barrier properties, optical characteristics, thermal stability, and shelf-life extension, are explored, showcasing their suitability for food packaging and other applications. Moreover, the application of 3D printing technology allows for customized designs and complex geometries, paving the way for personalized nutrition. Functionalization strategies, such as active and intelligent packaging, incorporation of bioactive compounds, and antimicrobial properties, are also discussed, offering additional functionalities and benefits. Challenges and future directions are identified, emphasizing the importance of sustainability, scalability, regulation, and performance optimization. The potential impact of plant-based materials and edible films is highlighted, ranging from reducing reliance on fossil fuels to mitigating plastic waste and promoting a circular economy. In conclusion, plant-based materials and edible films hold great potential in revolutionizing the packaging industry, offering sustainable alternatives to conventional materials. Embracing these innovations will contribute to reducing plastic waste, promoting a circular economy, and creating a sustainable and resilient planet.

Review on the extension of shelf life for fruits and vegetables using natural preservatives

Fruits and vegetables are important for the nutrition and health of individuals. They are highly perishable in nature because of their susceptibility to microbial growth. Foodborne pathogens create a significant problem for consumers, food businesses, and food safety. Postharvest factors, including transportation, environment, and preservation techniques, cause a reduction in product quality. The present world is using synthetic preservatives, which have negative impacts on consumer health. Food safety and demand for healthy foods among consumers, the scientific community, and the food industry resulted in the exploitation of natural preservatives, which play an important role in their effectiveness, prolonged shelf life, and safety. Natural preservatives include plants, animals, and microbiological sources with polymers to extend shelf life, improve quality, and enhance food safety. This review specifically focuses on mechanism of action of natural preservatives, spoilage of fruit and vegetables, the importance of edible film and coating on fruits and vegetables.

Development of multifunctional chitosan-based composite film loaded with tea polyphenol nanoparticles for strawberry preservation

Incorporating polysaccharide-based composite films with nanobiotechnology offers a new strategy for food preservation. This study initially focuses on the preparation of tea polyphenol nanoparticles (TPNP), novel and derived from natural antibacterial agents, which serve to improve stability. Afterwards chitosan-based composite films loaded with TPNP (CTN film) were developed using solution casting method. The incorporation of TPNP significantly improved the UV/water/oxygen barrier properties, mechanical properties and thermal stability, alongside notable physical properties including water contact angle (93.65 ± 0.04°), low water vapor permeability (33.72 ± 3.32 g/m2h) and oxygen permeability (0.11 ± 0.02 g/m2h), tensile strength (61.83 ± 0.70 %), and elongation at break (31.60 ± 6.12 %). The CTN film not only exhibited exceptional biodegradability and nontoxicity, but also demonstrated remarkable antimicrobial efficacy against Escherichia coli and Bacillus subtilis. Additionally, it showcased potent antioxidant activity, boasting DPPH and ABTS radical scavenging rates up to 89.25 ± 0.18 % and 93.84 ± 0.42 %. The CTN film was successfully formed on the surface of strawberries through dip-coating process and their shelf life was extended from 4 to 6 days at 20 °C without side-effect on the weight loss, harness, pH and total soluble solids, illustrating its potential for enhancing food preservation.

Synergistic modification of hot-melt extrusion and nobiletin on the multi-scale structures, interactions, thermal properties, and in vitro digestibility of rice starch

Background

Rice starch has high digestibility due to its large carbohydrate content. Synergistic modification of hot-melt extrusion (HME) and additives such as flavonoids, hydrocolloids, proteins, lipids, and other additives has the tendency to retard the rate of starch hydrolysis. Hence, the current investigation aimed to study the combined effect of the HME-assisted addition of nobiletin (NOB, 0, 2, 4, and 6%) on the multi-scale structures, interactions, thermal, and digestibility characteristics of rice starch.

Methods

The study employed density functional theory calculations and an infrared second derivative of an Fourier-transform infrared (FTIR) spectrometer to analyze the interactions between NOB and starch. The physicochemical properties of the starch extrudates were characterized by FTIR, 13C nuclear magnetic resonance, X-ray diffraction, and differential scanning calorimetry, while the digestibility was evaluated using an in vitro digestion model.

Results

HME was found to disrupt the crystalline structure, helix structure, short-ordered structure, and thermal properties of starch. The interaction between NOB and starch involved hydrophobic interactions and hydrogen bonds, effectively preventing the molecular chains of starch from interacting with each other and disrupting their double helix structure. The addition of NOB led to the formation of a highly single-helical V-type crystalline structure, along with the formation of ordered structural domains. Consequently, the combined treatment significantly enhanced the ordered structure and thermal stability of starch, thus effectively leading to an increase in resistant starch and slowly digestion starch.

Discussion

The study underscores that synergistic modification of HME and NOB holds promise for enhancing both the nutritional value and functional properties of rice starch. These findings offer valuable insights for developing high-quality rice starch products with broader applications.

Development and Physicochemical Characterization of Edible Chitosan-Casein Hydrogel Membranes for Potential Use in Food Packaging

The increasing global concern over plastic waste and its environmental impact has led to a growing interest in the development of sustainable packaging alternatives. This study focuses on the innovative use of expired dairy products as a potential resource for producing edible packaging materials. Expired milk and yogurt were selected as the primary raw materials due to their protein and carbohydrate content. The extracted casein was combined with various concentrations of chitosan, glycerol, and squid ink, leading to the studied samples. Chitosan was chosen due to its appealing characteristics, including biodegradability, and film-forming properties, and casein was utilized for its superior barrier and film-forming properties, as well as its biodegradability and non-toxic nature. Glycerol was used to further improve the flexibility of the materials. The prepared hydrogels were characterized using various instrumental methods, and the findings reveal that the expired dairy-based edible packaging materials exhibited promising mechanical properties comparable to conventional plastic packaging and improved barrier properties with zero-oxygen permeability of the hydrogel membranes, indicating that these materials have the potential to effectively protect food products from external factors that could compromise quality and shelf life.

Valorization of guinea grass seed (Megathyrsus maximus): Synthesis and utilization of cellulose microfiber to reinforce esterified and cross-linked guinea starch films

The present study extracts starch from guinea grass seed and fiber from the starch extraction residue. The fibrous residue was chemically converted into cellulose microfiber (CMF) and used to reinforce the native, esterified and crosslinked guinea starch films. The films were developed with 5 % starch, 40 % glycerol and 0, 2.5, 5, and 10 % CMF based on the dry matter of starch. SEM images of all film samples showed good compatibility of CMF with starch molecules, and no fractures or pores were observed. Adding filler materials to modified starch films slightly increased the film thickness (0.24 to 0.30 mm) due to the high dimensions of CMF, which comprise a significant amount of the composite's volume. A synergetic effect of starch modification and CMF in films decreased the moisture content (21.98 to 9.21 %), water solubility (25.65 to 15.47 %), water vapor permeability (6.96×10-7 to 1.65×10-7g∙mm2∙day∙Pa), and elongation at the break (33.51 to 16.79 %) while increasing the tensile strength (1.84 to 3.85 MPa) and Young's modulus (5.49 to 22.93 MPa). The L* and a* values of the films decreased, and the b* and opacity values of the films increased with the addition of CMF. The XRD graph showed that all films have semicrystalline structures with peaks at 18°, 20°, and 22°, and the degree of crystallinity increases (32.3 to 55.1 %) with CMF. All film samples showed good thermal stability up to 315 °C. In conclusion, esterified starch-based films exhibited superior barrier properties and flexibility. On the contrary, cross-linked starch films demonstrated higher tensile strength and lower water solubility.

Sodium alginate films incorporated with Lepidium sativum (Garden cress) extract as a novel method to enhancement the oxidative stability of edible oil

This study addresses the growing interest in bio-based active food packaging by infusing Lepidium sativum (Garden cress) seeds extract (GRCE) into sodium alginate (SALG) films at varying concentrations (1, 3, and 5 %). The GRCE extract revealed six phenolic compounds, with gallic and chlorogenic acids being prominent, showcasing substantial total phenolic content (TPC) of 139.36 μg GAE/mg and total flavonoid content (TFC) of 26.46 μg RE/mg. The integration into SALG films significantly increased TPC, reaching 30.73 mg GAE/g in the film with 5 % GRCE. This enhancement extended to DPPH and ABTS activities, with notable rises to 66.47 and 70.12 %, respectively. Physical properties, including tensile strength, thickness, solubility, and moisture content, were positively affected. A reduction in water vapor permeability (WVP) was reported in the film enriched with 5 % GRCE (1.389 × 10-10 g H2O/m s p.a.). FT-IR analysis revealed bands indicating GRCE's physical interaction with the SALG matrix, with thermal stability of the films decreasing upon GRCE integration. SALG/GRCE5 effectively lowered the peroxide value (PV) of sunflower oil after four weeks at 50 °C compared to the control, with direct film-oil contact enhancing this reduction. Similar trends were observed in the K232 and K270 values.

Development of CO2-sensitive antimicrobial bilayer films based on gellan gum and sodium alginate/sodium carboxymethyl cellulose and its application in strawberries

To effectively extend the shelf life of fruits meanwhile facilitating consumers to judge their freshness, in this work, a double-layer multifunctional film combining CO2 sensitivity and antibacterial properties was successfully prepared by adding methyl red (MR), bromothymol blue (BTB) into gellan gum (GG) as the sensing inner layer, and doping tannic acid (TA) into sodium alginate with sodium carboxymethyl cellulose (CMC) as the antimicrobial outer layer, which was applied to the freshness indication of strawberries. Microscopic morphology and spectral analysis demonstrated that the bi-layer films were fabricated successfully. The mechanical characteristics, thermal stability, water vapor resistance, and antibacterial capabilities of the bilayer films improved as TA concentration rose. They exhibited noticeable color changes at pH = 2-10 and different concentrations of CO2. Application of the prepared films to strawberries revealed that the GG-MB@SC-6%TA film performed most favorably under 4 °C storage conditions, not only monitoring strawberry freshness but also retaining high soluble solids and titratable acidity, resulting in a slight decrease in hardness and weight loss. Therefore, taking into account all of the physical-functional characteristics, the GG-MB@6%TA film has a broad application prospect for intelligent food packaging.

Alternative Additives for Organic and Natural Ready-to-Eat Meats to Control Spoilage and Maintain Shelf Life: Current Perspectives in the United States

Food additives are employed in the food industry to enhance the color, smell, and taste of foods, increase nutritional value, boost processing efficiency, and extend shelf life. Consumers are beginning to prioritize food ingredients that they perceive as supporting a healthy lifestyle, emphasizing ingredients they deem acceptable as alternative or "clean-label" ingredients. Ready-to-eat (RTE) meat products can be contaminated with pathogens and spoilage microorganisms after the cooking step, contributing to food spoilage losses and increasing the risk to consumers for foodborne illnesses. More recently, consumers have advocated for no artificial additives or preservatives, which has led to a search for antimicrobials that meet these demands but do not lessen the safety or quality of RTE meats. Lactates and diacetates are used almost universally to extend the shelf life of RTE meats by reducing spoilage organisms and preventing the outgrowth of the foodborne pathogen Listeria monocytogenes. These antimicrobials applied to RTE meats tend to be broad-spectrum in their activities, thus affecting overall microbial ecology. It is to the food processing industry's advantage to target spoilage organisms and pathogens specifically.

Addition of Silver Nanoparticles to Composite Edible Films and Coatings to Enhance Their Antimicrobial Activity and Application to Cherry Preservation

The aim of this study was to examine the potential enhancement of the antimicrobial activity of edible films, composed of (i) chitosan (CH), cellulose nanocrystals (CNC) and beta-cyclodextrin (CD) (50%-37.5%-12.5%) and (ii) hydroxypropyl methylcellulose (HPMC), cellulose nanocrystals (CNC) and beta-cyclodextrin (CD) (50%-37.5%-12.5%), with silver nanoparticle (AgNP) incorporationat levels 5, 10 and 15% v/v. According to the results, the AgNP addition led to very high antimicrobial activity of both films, reducing by more than 96% the microbial growth of the Gram-negative bacterium Escherichia coli (E. coli) in all cases. On the other hand, by adding AgNPs to films, their thickness as well as oxygen and water vapor permeability decreased, while their transparency increased. Furthermore, the contribution of these specific edible films to preserve cherries under cold storage was investigated. All edible coatings resulted in an improvement of the fruit properties under consideration, and especially the color difference, hardness and total microbial load.

Microstructural and Mechanical Properties of Calcium-Treated Cactus Pear Mucilage (Opuntia spp.), Pectin and Alginate Single-Biopolymer Films

Pectin and alginate satisfy multiple functional requirements in the food industry, especially relating to natural packaging formulation. The continuous need for economic and environmental benefits has promoted sourcing and investigating alternative biomaterials, such as cactus pear mucilage from the cladodes of Opuntia spp., as natural packaging alternatives. The structural and mechanical properties of mucilage, pectin and alginate films developed at a 5% (w/w) concentration were modified by treating the films with calcium (Ca) in the calcium chloride (CaCl2) form. Scanning electron microscopy (SEM) showed the 5% (w/w) 'Algerian' and 'Morado' films to display considerable microstructure variation compared to the 5% (w/w) pectin and alginate films, with calcium treatment of the films influencing homogeneity and film orientation. Treating the alginate films with a 10% (w/w) stock CaCl2 solution significantly increased (p < 0.05) the alginate films' tensile strength (TS) and puncture force (PF) values. Consequently, the alginate films reported significantly higher (p < 0.05) film strength (TS and PF) than the pectin + Ca and mucilage + Ca films. The mucilage film's elasticity was negatively influenced by CaCl2, while the pectin and alginate films' elasticity was positively influenced by calcium treatment. These results suggest that the overall decreased calcium sensitivity and poor mechanical strength displayed by 'the Algerian' and 'Morado' films would not make them viable replacements for the commercial pectin and alginate films unless alternative applications were found.

Edible coatings and films for shelf-life extension of fruit and vegetables

The execution of the edible coatings and films for food preservation; vegetables, fruits, meat, and dry fruits has been ladened in history. The study of literature portrays enough pieces of evidence dating back from centuries of coatings or films being utilized for the conservation of numerous fruits and vegetables to stretch their average shelf-life. The mechanism that remains operative in extending the shelf-life of fruits and vegetables beyond the normal shelf-life is the controlled entry and exit of moisture and gases. The non- biodegradable packaging which is also non-sustainable can be substituted with compostable and edible coatings and films made up of natural biopolymers. Therefore, keeping in mind the environment and consumer safety, a score of research has been going on from former decades for the development of edible coatings and films with efficient shelf life-extending qualities. The films composed of proteins exhibit a good mechanical strength while the polysaccharide composed films and coatings show efficient gas blocking qualities, however, both lack moisture shielding attributes. These shortcomings can be fixed by combining them with lipids and or some appropriate hydrocolloids. The edible coatings and films have been integrated with various food products; however, they haven't been completely successful in substitution of the total fraction of their non-edible counterparts. The implementation of edible coatings and films have shown to serve an immense value in extending the shelf-life of fruits and vegetables along with being a sustainable and eco-friendly approach for food packaging.

Edible Coatings and Future Trends in Active Food Packaging-Fruits' and Traditional Sausages' Shelf Life Increasing

The global food production industry faces environmental concerns exacerbated by substantial food waste. European countries are striving to reduce food waste towards a circular bioeconomy and sustainable development. To address environmental issues and reduce plastic waste, researchers are developing sustainable active packaging systems, including edible packaging made from industry residues. These innovations aim to increase food safety and quality, extend shelf life, and reduce plastic and food waste. Particularly important in the context of the growing demand for fresh and minimally processed fruits, edible coatings have emerged as a potential solution that offers numerous advantages in maintaining fruit quality. In addition to fruit, edible coatings have also been investigated for animal-based foods to meet the demand for high-quality, chemical-free food and extended shelf life. These products globally consumed can be susceptible to the growth of harmful microorganisms and spoilage. One of the main advantages of using edible coatings is their ability to preserve meat quality and freshness by reducing undesirable physicochemical changes, such as color, texture, and moisture loss. Furthermore, edible coatings also contribute to the development of a circular bioeconomy, promoting sustainability in the food industry. This paper reviews the antimicrobial edible coatings investigated in recent years in minimally processed fruits and traditional sausages. It also approaches bionanocomposites as a recently emerged technology with potential application in food quality and safety.

A Novel Approach about Edible Packaging Materials Based on Oilcakes-A Review

Due to the growing global population and subsequent environment degradation, as well as changes in the climate, changing consumers' dietary habits is necessary to create strategies for the most efficient use of natural resources to eliminate waste in the food supply chain. The packaging of food is essential to preserve the food's properties, extend its shelf life and offer nutritional information. Food products are packaged in various materials of which the most used are plastics, but they have a negative impact on the environment. Various efforts have been made to address this situation, but unfortunately, this includes recycling rather than replacing them with sustainable solutions. There is a trend toward edible packaging materials with more additional functions (antioxidant, antimicrobial and nutritional properties). Edible packaging is also a sustainable solution to avoid food waste and environment pollution. Oilcakes are the principal by-products obtained from the oil extraction process. These by-products are currently underused as animal feed, landfilling or compost. Because they contain large amounts of valuable compounds and are low-cost ingredients, they can be used to produce materials suitable for food packaging. This review covers the recent developments in oilcake-based packaging materials. Special emphasis is placed on the study of materials and technologies that can be used to make edible film in order to research the most suitable ways of developing oilcake-based film that can be consumed simultaneously with the product. These types of materials do not exist on the market.

Microbiological Assessment of White Button Mushrooms with an Edible Film Coating

The development of edible coatings incorporating bioextracts from mushrooms native to Portuguese forests aims to enhance the value of the endogenous forest and mycological resources by harnessing their potential as a source of antimicrobial and antioxidant compounds. Edible coatings represent an important pathway to decreasing food waste and contributing to implementing a circular bioeconomy. The coating should result in product valorization through improved preservation/conservation, increased shelf life, as well as enhancement of its antioxidant and enzymatic properties. To evaluate the effectiveness of an edible coating on fungal food matrices, a 14-day shelf-life study was conducted, wherein both coated and untreated mushrooms were examined under controlled storage temperatures of 4 °C and 9.3 °C. Agaricus bisporus was chosen as the food matrix for its bioeconomy significance, and Pleurotus eryngii was selected for the preparation of the food-based coating due to its profile of bioactive compounds. Microbiological analysis and physicochemical monitoring were conducted on the food matrices and the coating. Coated mushrooms had less mass loss and color change, and had better texture after 14 days. Microbiological analysis revealed that the coating had no antimicrobial activity. Overall, the coating improved the shelf life of the coated mushrooms but had less effect on the microbial community.

Preparation and Characterization of Novel Chitosan Coatings to Reduce Changes in Quality Attributes and Physiochemical and Water Characteristics of Mongolian Cheese during Cold Storage

The objective of this study was to evaluate the effect of O-carboxymethyl chitosan coating on microbiological, physiochemical, and water characteristics of Mongolian cheese during refrigerated storage. O-carboxymethyl chitosan coatings, particularly at 1.5%, improved cheese preservation by significantly inhibiting microbial growth, reducing changes in protein and non-protein nitrogen, and preserving pH and titratable acidity. For texture profile analysis (TPA), the hardness, gumminess, and chewiness in O-CMC treatments were significantly more stable than those in the control during storage. In addition, the relaxation component and image of nuclear magnetic resonance (NMR) were used to analyze the internal water mobility of the cheese during storage. Compared with other treatments, the 1.5% O-carboxymethyl chitosan coating had the best overall preserving effect during storage. O-carboxymethyl chitosan coating could be used in cheese preservation applications and could extend the shelf life of Mongolian cheese. The cheese coated with 1.5% O-carboxymethyl chitosan coating ranked the highest in acceptability at the end of the storage period.

Development of sodium alginate-pectin biodegradable active food packaging film containing cinnamic acid

Plastics are still the most popular food packaging material, and many of them end up in the environment for a long period. Besides, due to packaging material's inability to inhibit microbial growth, beef often contains microorganisms that affect its aroma, colour, and texture. Cinnamic acid is categorized as generally recognised as safe and is permitted for use in food, however, the development of biodegradable food packaging film with cinnamic acid has never been conducted before. Thus, this present study was aimed to develop a biodegradable active packaging material for fresh beef using sodium alginate and pectin. The film was successfully developed with solution casting method. The films' thickness, colour, moisture level, dissolution, water vapour permeability, bending strength, and elongation at break were comparable to those of polyethylene plastic film in terms of these attributes. The developed film also showed the degradability in soil of 43.26% in a duration of 15 days. Fourier Transform Infrared (FTIR) spectra showed that cinnamic acid was successfully incorporated with the film. The developed film showed significant inhibitory activity on all test foodborne bacteria. On Hohenstein Challenge Test, a 51.28-70.45% reduction on bacterial growth was also observed. The antibacterial efficacy of the established film by using fresh beef as food model. The meats wrapped with the film showed significant reduction in bacterial load throughout the experimental period by 84.09%. The colour of the beef also showed significant different between control film and edible film during 5 days test. Beef with control film turned into dark brownish and beef with cinnamic acid turn into light brownish. In conclusion, sodium alginate and pectin film with cinnamic acid showed good biodegradability and antibacterial activity. Further studies can be conducted to investigate the scalability and commercial viability of this environmental-friendly food packaging materials.

Application of Plant-Based Edible Coatings and Extracts Influences the Postharvest Quality and Shelf Life Potential of "Surahi" Guava Fruits

Guava fruits have a short shelf life due to climacteric nature. The current work was conducted to extend the shelf life of guavas with garlic extract (GRE), ginger extract (GNE), gum arabic (GA), and Aloe vera (AV) gel coatings. After coating, fruits of guava were stored at 25 ± 3 °C and RH 85 ± 2% for 15 days. Results showed that guavas treated with plant-based edible coatings and extracts had lower weight loss than that of the control. GRE-treated guavas had the maximum shelf life in contrast to all other treatments including the control. GNE-treated guavas showed the lowest nonreducing sugar content, whereas they had higher antioxidant activity, vitamin C content, and total phenolics compared with all other coating treatments. After the control, antioxidant capacity was the highest in GNE- and GRE-treated fruits. On the other hand, GA-treated guavas had reduced total soluble solids and juice pH (more acidic) and exhibited higher total flavonoids compared with the control, while both GA- and GNE-treated guavas had the highest flavonoid content. GRE-treated fruits exhibited the highest total sugar content and taste and aroma scores. In conclusion, GRE treatment was more effective in conserving the quality and extending the shelf life of guava fruits.

A Novel Edible Coating Produced from a Wheat Gluten, Pistacia vera L. Resin, and Essential Oil Blend: Antimicrobial Effects and Sensory Properties on Chicken Breast Fillets

Antimicrobial edible coatings can eliminate the risk of pathogen contamination on the surface of poultry products during storage. In this study, an edible coating (EC) based on wheat gluten, Pistacia vera L. tree resin (PVR), and the essential oil (EO) of PVR was applied on chicken breast fillets (CBF) by a dipping method to prevent the growth of Salmonella Typhimurium and Listeria monocytogenes. The samples were packed in foam trays wrapped with low-density polyethylene stretch film and stored at 8 °C for 12 days to observe the antimicrobial effects and sensory properties. The total bacteria count (TBC), L. monocytogenes, and S. Typhimurium were recorded during storage. The samples coated with EC, containing 0.5, 1, 1.5, and 2% v/v EO (ECEO), showed significant decreases in microbial growth compared to the control samples. The growth of TBC, L. monocytogenes, and S. Typhimurium was suppressed by 4.6, 3.2, and 1.6 logs, respectively, at the end of 12 days on the samples coated with ECEO (2%) compared to the uncoated controls (p < 0.05). Coating with ECEO (2%) also preserved the appearance, smell, and general acceptance parameters better than uncoated raw chicken (p < 0.05) on the fifth day of storage. In grilled chicken samples, ECEO (2%) did not significantly change the appearance, smell, and texture (p > 0.05) but increased the taste and general acceptance scores. Therefore, ECEO (2%) can be a feasible and reliable alternative to preserve CBFs without adversely affecting their sensory properties.

Himalayan Sources of Anthocyanins and Its Multifunctional Applications: A Review

Anthocyanins, the colored water-soluble pigments, have increasingly drawn the attention of researchers for their novel applications. The sources of anthocyanin are highly diverse, and it can be easily extracted. The unique biodiversity of the Himalayan Mountain range is an excellent source of anthocyanin, but it is not completely explored. Numerous attempts have been made to study the phytochemical aspects of different Himalayan plants. The distinct flora of the Himalayas can serve as a potential source of anthocyanins for the food industry. In this context, this review is an overview of the phytochemical studies conducted on Himalayan plants for the estimation of anthocyanins. For that, many articles have been studied to conclude that plants (such as Berberis asiatica, Morus alba, Ficus palmata, Begonia xanthina, Begonia palmata, Fragaria nubicola, etc.) contain significant amounts of anthocyanin. The application of Himalayan anthocyanin in nutraceuticals, food colorants, and intelligent packaging films have also been briefly debated. This review creates a path for further research on Himalayan plants as a potential source of anthocyanins and their sustainable utilization in the food systems.

Chitosan Membranes Containing Plant Extracts: Preparation, Characterization and Antimicrobial Properties

The main strategy of this study was to combine the traditional perspective of using medicinal extracts with polymeric scaffolds manufactured by an engineering approach to fabricate a potential dressing product with antimicrobial properties. Thus, chitosan-based membranes containing S. officinalis and H. perforatum extracts were developed and their suitability as novel dressing materials was investigated. The morphology of the chitosan-based films was assessed by scanning electron microscopy (SEM) and the chemical structure characterization was performed via Fourier transform infrared spectroscopy (FTIR). The addition of the plant extracts increased the sorption capacity of the studied fluids, mainly at the membrane with S. officinalis extract. The membranes with 4% chitosan embedded with both plant extracts maintained their integrity after being immersed for 14 days in incubation media, especially in PBS. The antibacterial activities were determined by the modified Kirby-Bauer disk diffusion method for Gram-positive (S. aureus ATCC 25923, MRSA ATCC 43300) and Gram-negative (E. coli ATCC 25922, P. aeruginosa ATCC 27853) microorganisms. The antibacterial property was enhanced by incorporating the plant extracts into chitosan films. The outcome of the study reveals that the obtained chitosan-based membranes are promising candidates to be used as a wound dressing due to their good physico-chemical and antimicrobial properties.

Advances in formulation, functionality, and application of edible coatings on fresh produce and fresh-cut products: A review

With the increasing population of the world food demand is also increasing but unfortunately, many countries in the world are lacking suitable and economical postharvest preservation techniques to minimize increasing postharvest losses. To ensure food security advanced production technologies, distribution systems and minimum losses should be ensured to give accessibility of food to all population groups. Innovative preservation techniques should be adopted by the agriculture sector to meet intercontinental distribution and demand for fresh produce. The application of the edible coating is a novel technique in postharvest preservation due to its simple application, ecofriendly nature, and effectiveness. Edible coatings can also improve the quality and safety aspects of fresh produce and thus extends shelf life. This review aimed to update information about recent advances in edible coating formulation and application mainly on fresh-cut /minimally processed fruits and vegetables. This information will be helpful for processors to select the best coating material and its effective concentration for different fresh and minimal processed vegetables.

Transglutaminase Cross-Linked and Lysozyme-Incorporated Antimicrobial Tilapia Collagen Edible Films: Development and Characterization

To improve the mechanical properties and confer antimicrobial activity, transglutaminase (TGase) was used as a cross-linking agent and lysozyme (LYS) was incorporated as an antimicrobial agent to prepare novel active tilapia collagen (TC) films. While the difference in visual appearance was not obvious, the LYS incorporation increased the opacity of TC films. The water vapor permeability of all TGase cross-linked TC films was significantly (p < 0.05) lower than that of the control film (prepared without TGase and LYS). In addition, while the tensile strength and Young’s modulus of all TGase cross-linked TC films were significantly (p < 0.05) higher than those of the control film, elongation at break of all TGase cross-linked TC films was significantly (p < 0.05) lower than that of the control film. LYS incorporated TC films showed antimicrobial activity against E. coli, Staphylococcus aureus, Enterococcus faecium, Bacillus subtilis and Pseudomonas fluorescens. Collectively, TC films with improved physiochemical properties and antimicrobial activity have a good potential to serve as active food packaging materials.

Application of Polysaccharide-Based Edible Coatings on Fruits and Vegetables: Improvement of Food Quality and Bioactivities

Most foods derived from plant origin are very nutritious but highly perishable products. Nowadays, the food industry is focusing on the development of efficient preservation strategies as viable alternatives to traditional packaging and chemical treatments. Hence, polysaccharide-based edible coatings have been proposed because of their properties of controlled release of food additives and the protection of sensitive compounds in coated foods. Thus, this technology has allowed for improving the quality parameters and extends the shelf life of fruits and vegetables through positive effects on enzyme activities, physicochemical characteristics (e.g., color, pH, firmness, weight, soluble solids), microbial load, and nutritional and sensory properties of coated foods. Additionally, some bioactive compounds have been incorporated into polysaccharide-based edible coatings, showing remarkable antioxidant and antimicrobial properties. Thus, polysaccharide-based edible coatings incorporated with bioactive compounds can be used not only as an efficient preservation strategy but also may play a vital role in human health when consumed with the food. The main objective of this review is to provide a comprehensive overview of materials commonly used in the preparation of polysaccharide-based edible coatings, including the main bioactive compounds that can be incorporated into edible coatings, which have shown specific bioactivities.

Effect of Chitosan and Alginate-Based Edible Membranes with Oregano Essential Oil and Olive Oil in the Microbiological, Physicochemical and Organoleptic Characteristics of Mutton

Edible chitosan or alginate coatings and their combinations with oregano essential oil or olive oil, have been examined for their effect on the microbiological, physicochemical and organoleptic characteristics of mutton. The results indicated that these edible coatings can contribute to maintaining good quality characteristics and extending mutton shelf-life. The total mesophilic counts in mutton ranged from 3.48 to 8.00 log¹⁰ CFU/g, the total psychrophilic counts from 4.00 to 9.50 log¹⁰ CFU/g, the B. thermosphacta counts from 2.30 to 7.77 log¹⁰ CFU/g and the lactic acid bacteria counts from 2.00 to 5.85 log¹⁰ CFU/g. Chitosan coatings significantly (p < 0.05) reduced the total mesophilic, the total psychrophilic (1-2 log₁₀ cfu/g), the B. thermosphacta and the lactic acid bacteria counts in mutton. Alginate exhibited a lower L* value and a higher a* value and chroma compared with the control and chitosan lots. No significant differences were observed in the chemical composition of meat pieces among the experimental groups. Oregano oil positively affected the sensory attributes of meat. The most favourable combination, based on the microbiological counts, the organoleptic characteristics and the shelf-life extension of mutton, was that of chitosan with oregano essential oil.

Using Response Surface Methodology to Optimize Edible Coating Formulations to Delay Ripening and Preserve Postharvest Quality of Tomatoes

Tomato is a nutrient-rich but highly perishable fruit. In order to delay the rapid ripening and degradation of fruits and reduce postharvest losses, response surface methodology (RSM) was used as the optimizing method to formulate edible coating based on pineapple peel extract and Arabic gum of twenty concentrations of pineapple (0.5–0.83 kg/l) and 20 concentrations of Arabic gum (5–15%, w/v). Tomatoes were soaked for 10–30 min in any of the coating solution. Five parameters including ripening rate, chlorophyll a content, firmness, total flavonoid content, and titratable acidity of tomatoes were evaluated after 8 days of storage at 24 ± 0.5°C and 82 ± 1.5% relative humidity. Results showed that the experimental data could be adequately fitted into a second-order polynomial model with coefficient of determination (R2) ranging from 0.775 to 0.976 for all the variables studied. The optimum concentrations were predicted as 0.70 kg/l pineapple peel extract and 17.04% with 18.72 min optimum time. Under these conditions, predicted values of response variables are as follows: ripening rate (RR) 40.75, chlorophyll a (Chl a) 8.11, firmness (Fir) 4.00, total flavonoid content (TFC) 43.51, and titratable acidity (TA) 0.30. It is concluded that RSM can be used to optimize pineapple peel extract and Arabic gum-based edible coating formulation to extend the shelf life or delay the ripening process of tomato fruit at ambient conditions.

Evaluation of the Efficacy of Antioxidant Extract from Lemon By-Products on Preservation of Quality Attributes of Minimally Processed Radish (Raphanus sativus L.)

The aim of this work was to enhance the use of a food-grade antioxidant extract obtained from lemon processing byproducts (peel, pulp and seeds) to extend the shelf life of minimally processed radishes. The extract (LPE) was previously characterized in terms of total phenolic (6.75 ± 0.34 mg GAE g-1 d.w.) and flavonoid content (2.04 ± 0.09 mg CE g-1 d.w.) and antioxidant activity, and eriocitrin and hesperidin were identified as the most prevalent phenolic compounds by a UHPLC system. The effects of different dipping aqueous solutions (UCR, DRa, DRb) and alginate-based edible coating formulations (CRc, CRd) with and without the antioxidant extract were studied on the quality parameters of minimally processed radishes, characterized regarding their microbiological and physicochemical characteristics for up to 14 days at 3 °C. The coating formulated with LPE delayed the radish respiration process, as well as resulting in less color variation (ΔE < 3) and reduced mesophilic aerobic count values (4.49 ± 1.43 log CFU g-1), proving the effectiveness of LPE as a value-added ingredient in developing post-harvest strategies to prolong the shelf life of minimally processed vegetables. Indeed, coated samples without the extract showed a clear development of rotting, which led to the end of their shelf life on their 7th day of storage.

Nanobacterial Cellulose Production and Its Antibacterial Activity in Biodegradable Poly(vinyl alcohol) Membranes for Food Packaging Applications

Nanobacterial cellulose (NBC) was produced and incorporated into biodegradable poly(vinyl alcohol) (PVA) in different weight ratios to obtain polymer nanocomposite membranes. The physicochemical properties of the membranes were studied using Fourier transform infrared (FTIR) spectroscopy, a universal testing machine (UTM), thermogravimetric analysis (TGA), wide-angle X-ray diffraction (WAXD) techniques, and field emission scanning electron microscopy (FESEM). FTIR confirmed the consolidation of NBC into PVA by exhibiting significant changes in the peaks compared to NBC and PVA individually. The highest tensile strength of 53.33 MPa and 235.30% elongation at break of the membrane M-10 mass % NBC was obtained, illuminating that NBC provides stiffness and PVA imparts elasticity. WAXD revealed that the crystalline nature of the membrane increases up to 10 mass % and decreases beyond it. The effect of NBC on the poly(vinyl alcohol) membranes for food packaging was investigated systematically. Among all the membranes, M-10 mass % NBC was found to be the most suitable for packaging applications. Membranes had antimicrobial activity against food microbes and showed degradability behavior in the soil. The tests on membranes for packaging revealed that fruits were protected from spoilage caused by microorganisms. Hence, the prepared membranes could be used as an alternative to conventional plastics for packaging applications.

Postharvest physiology and biochemistry of Valencia orange after coatings with chitosan nanoparticles as edible for green mold protection under room storage conditions

Because of their unique features, nanomaterials have been proposed and have gained acceptance in postharvest applications in fruit. Increasing the storage life and improving the quality of Valencia oranges was investigated using nano-chitosan. A chitosan nanoparticle was prepared by using high-energy ball milling. Chitosan nanoparticles were characterized by Dynamic light scattering, FTIR spectroscopy and Surface morphology by transmission electron microscopy. Fully mature Valencia oranges were harvested and then coated with one of these concentrations (0.2, 0.4, and 0.8% nano-chitosan) and control. The fruits were stored under room storage conditions for 75 days. The quality parameters (fruit weight losses, fruit decay percentage, fruit firmness, total acidity, total soluble solids percentage and T.S.S./acid ratio, ascorbic acid content) were taken in biweekly intervals after 0, 15, 30, 45, 60, and 75 days. Beside the in vitro testing of antifungal activity of chitosan nanoparticles. According to the findings of the two succeeding seasons, the nano-chitosan 0.8% treatment showed the best effects and had the lowest rate of fruit weight loss, fruit deterioration, and T.S.S./acid ratio in comparison to the other treatments in both seasons. Furthermore, the 0.8% nano-chitosan reveled the highest levels of fruit hardness and fruit pulp firmness. Fruit weight loss, fruit deterioration, TSS, and TSS/acid ratio, as well as other metrics, were steadily elevated prior to the storage time. The best results were obtained when Valencia oranges fruits were treated with 0.8% nano-chitosan for 75 days at room temperature.

Biopreservation of Refrigerated Mackerel (Auxis thazard) Slices by Rice Starch-Based Coating Containing Polyphenol Extract from Glochidion wallichianum Leaf

Both microbial decomposition and oxidative deterioration contribute to the qualitative degradation of fresh or minimally preserved fish, which negatively impacts the shelf-life of fish, especially those with dark flesh like mackerel. It is becoming more typical to use edible coatings to preserve the freshness of fish products. Herein, the effects of a rice starch (RS) based coating incorporated with dried crude, aqueous Mon-pu (Glochidion wallichianum) leaf extract (MPE) at varying concentrations (0, 0.02, 0.1, 0.5, and 1.0% w/w) on the quality characteristics of mackerel (Auxis thazard) slices during storage at 4 °C were investigated. Uncoated slices had a shelf-life of 6 days, whereas samples coated with RS and 0.5% MPE extended the shelf-life to 9 days by keeping the overall microbiological quality below the permitted level of 6 log CFU/g. The changes in thiobarbituric acid reactive substances (TBARS; <2 mg malondialdehyde equivalent/kg), propanal content, heme iron degradation, myoglobin redox instability, and surface discoloration (a* value and total color difference; ΔE) can all be delayed by this coating condition. Additionally, the RS-MPE coating can maintain the sensory quality of refrigerated mackerel slices and preserve the textural property (water holding capacity and hardness), as well as postpone the development of an off-odor as indicated by lowered contents of total volatile base-nitrogen (TVB-N; not exceeding the acceptable limit of 25 mg/100 g) and trimethylamine (TMA; not exceeding the acceptable limit of 10 mg/100 g). Therefore, a biopreservative coating made of RS and MPE, especially at 0.5%, can be employed to extend the shelf-life of refrigerated mackerel slices up to 9 days.

Production of biopolymers from food waste: Constrains and perspectives

Food is an essential commodity for the survival of any form of life on earth. Yet generation of plethora of food waste has significantly elevated the global concern for food scarcity, human and environment deterioration. Also, increasing use of polymers derived from petroleum hydrocarbons has elevated the concerns towards the depletion of this non-renewable resource. In this review, the use of waste food for the production of bio-polymers and their associated challenges has been thoroughly investigated using scientometric analysis. Various categories of food waste including fruit, vegetable, and oily waste can be employed for the production of different biopolymers including polyhydroxyalkanoates, starch, cellulose, collagen and others. The advances in the production of biopolymers through chemical, microbial or enzymatic process that increases the acceptability of these biopolymers has been reviewed. The comprehensive compiled information may assist researchers for addressing and solving the issues pertaining to food wastage and fossil fuel depletion.

A Comprehensive Review of Biodegradable Polymer-Based Films and Coatings and Their Food Packaging Applications

Food sectors are facing issues as a result of food scarcity, which is exacerbated by rising populations and demand for food. Food is ordinarily wrapped and packaged using petroleum-based plastics such as polyethylene, polyvinyl chloride, and others. However, the excessive use of these polymers has environmental and health risks. As a result, much research is currently focused on the use of bio-based materials for food packaging. Biodegradable polymers that are compatible with food products are used to make edible packaging materials. These can be ingested with food and provide consumers with additional health benefits. Recent research has shifted its focus to multilayer coatings and films-based food packaging, which can provide a material with additional distinct features. The aim of this review article is to investigate the properties and applications of several bio-based polymers in food packaging. The several types of edible film and coating production technologies are also covered separately. Furthermore, the use of edible films and coatings in the food industry has been examined, and their advantages over traditional materials are also discussed.