Technological, applications, and characteristics of edible films and coatings: a review

Recent biotechnological applications of value-added bioactive compounds from microalgae and seaweeds

Microalgae and seaweed have been consumed as food for several decades to combat starvation and food shortages worldwide. The most famous edible microalgae species are Nostoc, Spirulina, and Aphanizomenon, in addition to seaweeds, which are used in traditional medicine and food, such as Nori, which is one of the most popular foods containing Pyropia alga as a major ingredient. Recently, many applications use algae-derived polysaccharides such as agar, alginate, carrageenan, cellulose, fucoidan, mannan, laminarin, ulvan, and xylan as gelling agents in food, pharmaceuticals, and cosmetics industries. Moreover, pigments (carotenoids particularly astaxanthins, chlorophylls, and phycobilins), minerals, vitamins, polyunsaturated fatty acids, peptides, proteins, polyphenols, and diterpenes compounds are accumulated under specific cultivation and stress conditions in the algal cells to be harvested and their biomass used as a feedstock for the relevant industries and applications. No less critical is the use of algae in bioremediation, thus contributing significantly to environmental sustainability.This review will explore and discuss the various applications of microalgae and seaweeds, emphasising their role in bioremediation, recent products with algal added-value compounds that are now on the market, and novel under-developing applications such as bioplastics and nanoparticle production. Nonetheless, special attention is also drawn towards the limitations of these applications and the technologies applied, and how they may be overcome.

The potential of carboxylmethyl cellulose from empty fruit bunch as versatile material in food coating: A review

The rising demand for food packaging has led to a growing interest in sustainable and eco-friendly food coatings. Carboxymethyl cellulose (CMC), being a versatile cellulose derivative produced from various lignocellulosic sources, has emerged in edible food coatings. This review evaluates the research trends on CMC production from empty fruit bunch (EFB) as a potential edible food coating material by systematic review approach. It explores sustainable pre-treatment for green cellulose and different CMC synthesis methods. The review compares CMC-based coatings to other materials, focusing on formulation processes, coating quality, safety, and commercial feasibility. The bibliometric analysis is performed to correlate food coating and CMC. As a result, the study discovered the rapid growth in research on edible food coatings made from CMC for various food industry applications. The green approach such as ozone pre-treatment appear as promising method for cellulose isolation from EFB to be used as raw material for CMC. The synthesis conditions of the treatment would affect the CMC characteristics and usage. Herein, utilizing CMC from cellulose EFB in coating formulation and on coated food shows different benefits. This review provides a road map for future research with potential to make important contributions to the food industry's long-term evolution.

Fabrication of a self-healing hydrogel with antibacterial activity using host-guest interactions between dopamine-modified alginate and β-cyclodextrin dimer

Self-healing hydrogels possess an ability to recover their functionality after experiencing damage by regenerating cross-links. The main challenge in making self-healing hydrogels based on host-guest (HG) interactions is their limited mechanical strength, which can be solved using beta-cyclodextrin dimers (β-CDsD). Here, β-CDsD as a host cross-linker was used to increase the mechanical property of the HG interactions. Alginate with acceptable biocompatibility was modified by dopamine (ALG-DOP) and employed as a guest polymer. Self-healing hydrogel was developed between them, and Ag nanoparticles were added to create an antibacterial activity. Dopamine with appropriate size and suitable adhesiveness established HG interactions with β-CDsD, and cells were able to grow well on hydrogel. This hydrogel showed an impressive self-healing capability <5 min. These hydrogels revealed a respectable porosity from 15 to 55 μm essential for exchanging the substances required for cell growth and cell waste elimination. Biocompatibility was investigated against NIH 3 T3 fibroblasts cells, and the results showed that the cells grew well. The in vitro release of curcumin from the hydrogel was examined in PBS at pH of 7.4. The hydrogel can be a perfect candidate for controlled drug release, and wound-dressing due to self-healing property, antibacterial activity, adhesion, and biocompatibility.

The present state and future outlook of pectin-based nanoparticles in the stabilization of Pickering emulsions

The stabilization of Pickering emulsions using micro/nanoparticles has gained significant attention due to their wide range of potential applications in industries such as cosmetics, food, catalysis, tissue engineering, and drug delivery. There is a growing demand for the development of environmentally friendly micro/nanoparticles to create stable Pickering emulsions. Naturally occurring polysaccharides like pectin offer promising options as they can assemble at oil/water interfaces. This polysaccharide is considered a green candidate because of its biodegradability and renewable nature. The physicochemical properties of micro/nanoparticles, influenced by fabrication methods and post-modification techniques, greatly impact the characteristics and applications of the resulting Pickering emulsions. This review focuses on recent advancements in Pickering emulsions stabilized by pectin-based micro/nanoparticles, as well as the application of functional materials in delivery systems, bio-based films and 3D printing using these emulsions as templates. The effects of micro/nanoparticle properties on the characteristics of Pickering emulsions and their applications are discussed. Additionally, the obstacles that currently hinder the practical implementation of pectin-based micro/nanoparticles and Pickering emulsions, along with future prospects for their development, are addressed.

Enhancing Tensile Strength, Thermal Stability, and Antioxidant Characteristics of Transparent Kappa Carrageenan Films Using Grapefruit Essential Oil for Food Packaging Applications

The trends in food packaging technologies are shifting toward utilizing natural and environmentally friendly materials prepared from biopolymers such as kappa carrageenan to replace synthetic polymers. In the current study, varying amounts (0.1, 0.2, and 0.3%) of grapefruit essential oil (GFO) were incorporated in kappa carrageenan-based edible films to improve their physicochemical properties. The developed film samples were characterized for their barrier, mechanical, morphological, optical, thermal, antioxidant, and biodegradable properties. The results obtained showed that the tensile strength of the carrageenan films enhanced significantly from 65.20 ± 4.71 to 98.21 ± 6.35 MPa with the incorporation of GFO in a concentration-dependent manner. FTIR and SEM analysis confirmed the intermolecular bonding between carrageenan and GFO, resulting in the formation of compact films. Incorporating GFO significantly enhanced the thermal resistance of oil-loaded films, as confirmed by TGA, DSC, and DTG analysis. The addition of GFO led to a substantial increase in the radical scavenging activity of the films, as evidenced by the DPPH and ABTS assays. Furthermore, the developed films were biodegradable in soil and seawater environments, indicating their potential as a sustainable alternative to traditional plastics. Findings demonstrated that GFO can be used as a natural antioxidant agent in kappa carrageenan-based films for potential applications in food packaging.

Development and characterization of pomegranate peel extract-functionalized jackfruit seed starch-based edible films and coatings for prolonging the shelf life of white grapes

In the current research, the pomegranate peel extract of varying concentrations (0.02, 0.04, 0.06, 0.08, and 0.1 g/mL) were incorporated into jackfruit seed starch (5 % w/w) based edible films and coatings for the evaluation their effects on the mechanical, physical, barrier and thermal properties. Furthermore, the effects of the optimized edible coating were investigated on the postharvest shelf life of white grapes at room storage (30 ± 5 °C, RH = 70 ± 5 %) conditions for up to 8 days. The obtained results showed a significant increment in thickness (p ≤ 0.05) with higher concentration (0.1 g/mL) of pomegranate peel extract (PPE), total phenolic content (959.33 ± 43.36 mg/100 g) and antioxidant activity (87.35 ± 1.64 %) of the prepared edible films but have negative impacts on the water vapor permeability (2.82 × 10-6 ± 6.48 × 10-7 g-1h-1pa-1) and oxygen permeability (1.62 × 10-14 ± 9.32 × 10-15 cm3·cm/cm2·s·cmHg), solubility (23.24 ± 3.21 %), and tensile strength (1.60 ± 0.43 MPa). The edible film enriched with 0.4 g/mL of PPE showed higher thermal stability in terms of glass transition temperature (98.2 ± 0.21 °C) and peak temperature (110.3 ± 0.35 °C). Additionally, the application of coating treatment significantly maintains the postharvest shelf life of white grapes throughout the storage period.

Novel applications of black pepper essential oil as an antioxidant agent in sodium caseinate and chitosan based active edible films

In the current study, sodium caseinate and chitosan-based composite edible films were developed with the incorporation of black pepper (Piper nigrum) essential oil (BPO) in various concentrations (0.05, 0.1 and 0.15 %) for potential food packaging applications. The chemical composition of BPO was determined using GCMS and the major compound detected were β-caryophyllene, limonene, β-phellandren, pinene, copaene and α-humulene. The addition of BPO resulted in an increase in the thickness, EAB, WVP, moisture content and swelling index values of the films; however, the TS and water solubility decreased. The inclusion of BPO led to a substantial enhancement in the DPPH and ABTS radical scavenging capabilities of the edible films. SEM micrographs demonstrated intermolecular interaction between BPO, sodium caseinate, and chitosan. FTIR spectra confirmed the interaction of the functional groups of the polymers and BPO. The incorporation of the BPO increased the crystallinity of the films. Moreover, the thermal analysis including TGA, DSC and DTG demonstrated an increase in the thermal stability of the edible films with the addition of the BPO. These findings demonstrated that sodium caseinate and chitosan composite based edible films loaded with BPO can be used as sustainable active food packaging material.

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.

Recent advances in edible coatings and their application in food packaging

The food packaging industries are facing the challenge of food waste generation. This can be addressed through the use of edible coating materials. These coatings aid in extending the shelf life of food products, reducing waste. The key components of these coatings include food-grade binding agents, solvents, and fillers. The integration of polysaccharide, protein, lipids, bioactive and composite-based materials with edible coating matrix aids to combat substantial post-harvest loss of highly perishable commodities and elevates the quality of minimally processed food. The aim of this review is to introduce the concept of edible coatings and discuss the different coating materials used in the food industry, along with their properties. Additionally, this review aims to classify the coating types based on characteristic features and explore their application in various food processing industries. This review provides a comprehensive overview of edible coatings, including the integration of polysaccharides, proteins, lipids, bioactive, and composite-based materials into the coating matrix. This review also addresses the significant post-harvest loss of highly perishable commodities and emphasizes the enhancement of quality in minimally processed food. Furthermore, the antimicrobial, anti-corrosive, and edible characteristics are highlighted, showcasing their potential applications in different food packaging industries. Moreover, it also discusses the challenges, safety and regulatory aspects, current trends, and future perspectives, aiming to shed light on the commercialization and future investigation of edible coatings.

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.

Nanocellulose-stabilized Pickering emulsions: Fabrication, stabilization, and food applications

Pickering emulsions have been widely studied due to their good stability and potential applications. Nanocellulose including cellulose nanocrystals (CNCs), cellulose nanofibrils (CNFs), and bacterial cellulose nanofibrils (BCNFs) has emerged as sustainable stabilizers/emulsifiers in food-related Pickering emulsions due to their favorable properties such as renewability, low toxicity, amphiphilicity, biocompatibility, and high aspect ratio. Nanocellulose can be widely obtained from different sources and extraction methods and can effectively stabilize Pickering emulsions via the irreversible adsorption onto oil-water interface. The synergistic effects of nanocellulose and other substances can further enhance the interfacial networks. The nanocellulose-based Pickering emulsions have potential food-related applications in delivery systems, food packaging materials, and fat substitutes. Nanocellulose-based Pickering emulsions as 3D printing inks exhibit good injectable and gelling properties and are promising to print spatial architectures. In the future, the utilization of biomass waste and the development of "green" and facile extraction methods for nanocellulose production deserve more attention. The stability of nanocellulose-based Pickering emulsions in multi-component food systems and at various conditions is an utmost challenge. Moreover, the case-by-case studies on the potential safety issues of nanocellulose-based Pickering emulsions need to be carried out with the standardized assessment procedures. In this review, we highlight key fundamental work and recent reports on nanocellulose-based Pickering emulsion systems. The sources and extraction of nanocellulose and the fabrication of nanocellulose-based Pickering emulsions are briefly summarized. Furthermore, the synergistic stability and food-related applications of nanocellulose-stabilized Pickering emulsions are spotlighted.

A critical review on protein-based smart packaging systems: Understanding the development, characteristics, innovations, and potential applications

The use of packaging in the food industry is essential to protect food and improve its shelf life. However, traditional packaging, based on petroleum derivatives, presents some problems because it is non-biodegradable and is obtained from nonrenewable sources. In contrast, protein-based smart packaging is presented as an environmentally friendly strategy that also permits obtaining packaging with excellent characteristics for the formation of smart films and coatings. This review aims to summarize recent developments in smart packaging, focusing on edible films/coatings materials, originating from animal and plant protein sources. Various characteristics like mechanical, barrier, functional, sensory, and sustainability of packaging systems are discussed, and the processes used for their development are also described. Moreover, relevant examples of the application of these smart packaging technologies in muscle foods and some innovations in this area are presented. Protein-based films and coatings from plant and animal origins have great potential to enhance food safety and quality, and reduce environmental issues (e.g., plastic pollution and food waste). Some characteristics of the packages can be improved by incorporating polysaccharides, lipids, and other components as antioxidants, antimicrobials, and nanoparticles in protein-based composites. Promising results have been shown in many muscle foods, such as meat, fish, and other seafood. These innovative smart packaging systems are characterized by their renewable and biodegradable nature, and sustainability, among other features that go beyond typical protection barriers (namely, active, functional, and intelligent features). Nonetheless, the utilization of protein-based responsive films and coatings at industrial level still need optimization to be technologically and economically valid and viable.

Prevention of Fungal Contamination in Semi-Hard Cheeses by Whey–Gelatin Film Incorporated with Levilactobacillus brevis SJC120

Cheese whey fermented by lactic acid bacteria (LAB) was used to develop an edible film with antifungal properties. Five LAB strains isolated from artisanal cheeses were screened for antifungal activity and incorporated into a whey–gelatin film. Of the strains tested, Levilactobacillus brevis SJC120 showed the strongest activity against five filamentous fungi isolated from cheese and cheese-making environment, at both 10 °C and 20 °C. The cell-free supernatant from L. brevis inhibited fungal growth by more than 80%. Incorporation of bacterial cells into the film did not alter the moisture content, water vapor permeability, or mechanical and optical properties. The whey–gelatin film was also able to maintain the viability of L. brevis cells at 107 log CFU/g after 30 days at 10 °C. In cheeses wrapped with L. brevis film, the size of fungal colonies decreased by 55% to 76%. Furthermore, no significant differences (p > 0.05) were observed in cheese proteolysis or in the moisture, fat, and protein content of the cheese wrapped with films. The results showed that whey–gelatin film with L. brevis SJC120 can reduce the contamination of cheese with filamentous fungi and could be used as an alternative to conventional cheese preservation and packaging.

Silk Sericin Protein Materials: Characteristics and Applications in Food-Sector Industries

There is growing concern about the use of plastic in packaging for food materials, as this results in increased plastic waste materials in the environment. To counter this, alternative sources of packaging materials that are natural and based on eco-friendly materials and proteins have been widely investigated for their potential application in food packaging and other industries of the food sector. Sericin, a silk protein that is usually discarded in large quantities by the sericulture and textile industries during the degumming process of manufacturing silk from silk cocoons, can be explored for its application in food packaging and in other food sectors as a functional food and component of food items. Hence, its repurposing can result in reduced economic costs and environmental waste. Sericin extracted from silk cocoon possesses several useful amino acids, such as aspartic acid, glycine, and serine. Likewise, sericin is strongly hydrophilic, a property that confers effective biological and biocompatible characteristics, including antibacterial, antioxidant, anticancer, and anti-tyrosinase properties. When used in combination with other biomaterials, sericin has proved to be effective in the manufacture of films or coating or packaging materials. In this review, the characteristics of sericin materials and their potential application in food-sector industries are discussed in detail.

Physicochemical and Antimicrobial Characterization of Chitosan and Native Glutinous Rice Starch-Based Composite Edible Films: Influence of Different Essential Oils Incorporation

Biopolymer-based edible packaging is an effective way of preserving food while protecting the environment. This study developed an edible composite film using chitosan and native glutinous rice starch (NGRS) and incorporated essential oils (EOs) such as garlic, galangal, turmeric, and kaffir lime at fixed concentrations (0.312 mg/mL) to test its physicochemical and antimicrobial properties. The EO-added films were found to significantly improve the overall color characteristics (lightness, redness, and yellowness) as compared to the control film. The control films had higher opacity, while the EO-added films had slightly reduced levels of opacity and produced clearer films. The tensile strength and elongation at break values of the films varied among the samples. The control samples had the highest tensile strength, followed by the turmeric EO-added samples. However, the highest elongation at break value was found in the galangal and garlic EO-added films. The Young's modulus results showed that garlic EO and kaffir lime EO had the lowest stiffness values. The total moisture content and water vapor permeability were very low in the garlic EO-added films. Despite the differences in EOs, the Fourier-transform infrared spectroscopy (FTIR) patterns of the tested films were similar among each other. Microstructural observation of the surface and cross-section of the tested edible film exhibited smooth and fissureless patterns, especially in the EO-added films, particularly in the galangal and kaffir lime EO-added films. The antimicrobial activity of the EO-added films was highly efficient against various gram-positive and gram-negative pathogens. Among the EO-added films, the garlic and galangal EO-added films exhibited superior inhibitory activity against Escherichia coli, Salmonella Typhimurium, Listeria monocytogenes, Staphylococcus aureus, and Pseudomonas fluorescence, and turmeric and kaffir lime EO-added films showed potential antimicrobial activity against Lactobacillus plantarum and L. monocytogenes. Overall, this study concludes that the addition of EOs significantly improved the physicochemical and antimicrobial properties of the CH-NGRS-based edible films, making them highly suitable for food applications.

The strategic applications of natural polymer nanocomposites in food packaging and agriculture: Chances, challenges, and consumers' perception

Natural polymer-based nanocomposites have received significant attention in both scientific and industrial research in recent years. They can help to eliminate the consequences of application of petroleum-derived polymeric materials and related environmental concerns. Such nanocomposites consist of natural biopolymers (e.g., chitosan, starch, cellulose, alginate and many more) derived from plants, microbes and animals that are abundantly available in nature, biodegradable and thus eco-friendly, and can be used for developing nanocomposites for agriculture and food industry applications. Biopolymer-based nanocomposites can act as slow-release nanocarriers for delivering agrochemicals (fertilizers/nutrients) or pesticides to crop plants to increase yields. Similarly, biopolymer-based nanofilms or hydrogels may be used as direct product coating to extend product shelf life or improve seed germination or protection from pathogens and pests. Biopolymers have huge potential in food-packaging. However, their packaging properties, such as mechanical strength or gas, water or microbial barriers can be remarkably improved when combined with nanofillers such as nanoparticles. This article provides an overview of the strategic applications of natural polymer nanocomposites in food and agriculture as nanocarriers of active compounds, polymer-based hydrogels, nanocoatings and nanofilms. However, the risk, challenges, chances, and consumers' perceptions of nanotechnology applications in agriculture and food production and packaging have been also discussed.

Properties and Biodegradability of Films Based on Cellulose and Cellulose Nanocrystals from Corn Cob in Mixture with Chitosan

The increase in consumer demand for more sustainable packaging materials represents an opportunity for biopolymers utilization as an alternative to reduce the environmental impact of plastics. Cellulose (C) and chitosan (CH) are attractive biopolymers for film production due to their high abundance, biodegradability and low toxicity. The objective of this work was to incorporate cellulose nanocrystals (NC) and C extracted from corn cobs in films added with chitosan and to evaluate their properties and biodegradability. The physicochemical (water vapor barrier, moisture content, water solubility and color) and mechanical properties of the films were evaluated. Component interactions using Fourier-transform infrared (FTIR) spectroscopy, surface topography by means of atomic force microscopy (AFM), biodegradability utilizing a fungal mixture and compostability by burying film discs in compost were also determined. The C-NC-CH compared to C-CH films presented a lower moisture content (17.19 ± 1.11% and 20.07 ± 1.01%; w/w, respectively) and water vapor permeability (g m−1 s−1 Pa−1 × 10−12: 1.05 ± 0.15 and 1.57 ± 0.10; w/w, respectively) associated with the NC addition. Significantly high roughness (Rq = 4.90 ± 0.98 nm) was observed in films added to NC, suggesting a decreased homogeneity. The biodegradability test showed larger fungal growth on C-CH films than on CH films (>60% and <10%, respectively) due to the antifungal properties of CH. C extracted from corn cobs resulted in a good option as an alternative packaging material, while the use of NC improved the luminosity and water barrier properties of C-CH films, promoting strong interactions due to hydrogen bonds.

An insight to potential application of synbiotic edible films and coatings in food products

Edible films and coatings have gained significant consideration in recent years due to their low cost and decreasing environmental pollution. Several bioactive compounds can be incorporated into films and coatings, including antioxidants, antimicrobials, flavoring agents, colors, probiotics and prebiotics. The addition of probiotics to edible films and coatings is an alternative approach for direct application in food matrices that enhances their stability and functional properties. Also, it has been noted that the influence of probiotics on the film properties was dependent on the composition, biopolymer structure, and intermolecular interactions. Recently, the incorporation of probiotics along with prebiotic compounds such as inulin, starch, fructooligosaccharide, polydextrose and wheat dextrin has emerged as new bioactive packaging. The simultaneous application of probiotics and prebiotics improved the viability of probiotic strains and elevated their colonization in the intestinal tract and provided health benefits to humans. Moreover, prebiotics created a uniform and compact structure by filling the spaces within the polymer matrix and increased opacity of edible films. The effects of prebiotics on mechanical and barrier properties of edible films was dependent on the nature of prebiotic compounds. This review aims to discuss the concept of edible films and coatings, synbiotic, recent research on synbiotic edible films and coatings as well as their application in food products.

Characterization of Antimicrobial Composite Edible Film Formulated from Fermented Cheese Whey and Cassava Peel Starch

Antimicrobial composite edible film can be a solution for environmentally friendly food packaging, which can be made from fermented cheese whey containing an antimicrobial agent and cassava peel waste that contains starch. The research aims to determine the formulation of fermented cheese whey and cassava peel waste starch, resulting in an antimicrobial composite edible film with the best physical, mechanical, and water vapour permeability (WVP) properties, as well as with high antimicrobial activity. This research was conducted using experimental methods with nine composite edible film formulation treatments with three replications. Three variations in the fermented cheese whey and cassava peel starch ratio (v/v) (1:3, 1:1, 3:1) were combined with variations in the addition of glycerol (20%, 33%, 45%) (w/w) in the production of the composite edible film. Then, the physical characteristics such as elongation at break, tensile strength, WVP, colour, and antimicrobial effect of its film-forming solution were observed. The results showed that 24 h of whey fermentation with Candida tropicalis resulted in an 18.50 mm inhibition zone towards Pseudomonas aeruginosa. The best characteristic of the film was obtained from the formulation of a whey:starch ratio of 1:3 and 33% glycerol, which resulted in a thickness value of 0.21 mm, elongation at break of 19.62%, tensile strength of 0.81 N/mm², WVP of 3.41 × 10⁻¹⁰·g/m·s·Pa at a relative humidity (RH) of 100%–35%, and WVP of 9.84 × 10⁻¹⁰·g/m·s·Pa at a RH of 75%–35%, with an antimicrobial activity towards P. aeruginosa of 5.11 mm.

Supraparticles with a Mechanically Triggerable Color-Change-Effect to Equip Coatings with the Ability to Report Damage

Small scratches and abrasion cause damage to packaging coatings. Albeit often invisible to the human eye, such small defects in the coating may ultimately have a strong negative impact on the whole system. For instance, gases may penetrate the coating and consequently the package barrier, thus leading to the degradation of sensitive goods. Herein, the indicators of mechanical damage in the form of particles are reported, which can readily be integrated into coatings. Shear stress-induced damage is indicated by the particles via a color change. The particles are designed as core-shell supraparticles. The supraparticle core is based on rhodamine B dye-doped silica nanoparticles, whereas the shell is made of alumina nanoparticles. The alumina surface is functionalized with a monolayer of a perylene dye. The resulting core-shell supraparticle system thus contains two colors, one in the core and one in the shell part of the architecture. Mechanical damage of this structure exposes the core from the shell, resulting in a color change. With particles integrated into a coating lacquer, mechanical damage of a coating can be monitored via a color change and even be related to the degree of oxygen penetration in a damaged coating.

Applications of Microbial Exopolysaccharides in the Food Industry

Exopolysaccharides (EPSs) are high molecular weight polysaccharides secreted by microorganisms in the surrounding environment. In addition to the favorable benefits of these compounds for microorganisms, including microbial cell protection, they are used in various food, pharmaceutical, and cosmetic industries. Investigating the functional and health-promoting characteristics of microbial EPS, identifying the isolation method of these valuable compounds, and their applications in the food industry are the objectives of this study. EPS are used in food industries as thickeners, gelling agents, viscosifiers, and film formers. The antioxidative, anticancer, prebiotic, and cholesterol-lowering effects of some of these compounds make it possible to use them in functional food production.

Potentials of polysaccharides, lipids and proteins in biodegradable food packaging applications

Bio-based packaging materials are gaining importance due to their biodegradability, sustainability and environmental friendliness. To control the food quality and improve the food safety standards, proteins polysaccharide and lipid-based packaging films are enriched with bioactive and functional substances. However, poor permeability and mechanical characteristics are the challenging areas in their commercialization. Scientists and researchers are using a combination of techniques i.e. hydrogels, crosslinking, etc. to improve the intermolecular forces between different components of the film formulation to counter these challenges More recently, biodegradable packaging materials, sometimes edible, are also used for the delivery of functional ingredients which reveals their potential for drug delivery to counter the nutrient deficiency problems. This study highlights the potentials of bio-based materials i.e. proteins, polysaccharides, lipids, etc. to develop biodegradable packaging materials. It also explores the additives used to improve the physicochemical and mechanical properties of biodegradable packaging materials. Furthermore, it highlights the novel trends in biodegradable packaging from a food safety and quality point of view.

Development of Chitosan/Peptide Films: Physical, Antibacterial and Antioxidant Properties

Chitosan/peptide films were prepared by incorporating peptides (0.4%, w/v) from soy, corn and caseins into chitosan films. The presence of peptides significantly affected the physical, antibacterial and antioxidative properties of chitosan films. Among these films, those containing corn peptide showed the best water vapor barrier properties, and the tensile strength and elongation at break increased to 24.80 Mpa and 23.94%, respectively. Characterization of surface hydrophobicity and thermal stability suggested the strongest intermolecular interactions between corn peptides and chitosan. Moreover, films containing casein peptides showed the highest antibacterial activity and radical scavenging activity. The DPPH scavenging rate of films containing casein peptides reached 46.11%, and ABTS scavenging rate reached 66.79%. These results indicate the chitosan/peptide films may be promising food packaging materials.

Alginate: From Food Industry to Biomedical Applications and Management of Metabolic Disorders

Initially used extensively as an additive and ingredient in the food industry, alginate has become an important compound for a wide range of industries and applications, such as the medical, pharmaceutical and cosmetics sectors. In the food industry, alginate has been used to coat fruits and vegetables, as a microbial and viral protection product, and as a gelling, thickening, stabilizing or emulsifying agent. Its biocompatibility, biodegradability, nontoxicity and the possibility of it being used in quantum satis doses prompted scientists to explore new properties for alginate usage. Thus, the use of alginate has been expanded so as to be directed towards the pharmaceutical and biomedical industries, where studies have shown that it can be used successfully as biomaterial for wound, hydrogel, and aerogel dressings, among others. Furthermore, the ability to encapsulate natural substances has led to the possibility of using alginate as a drug coating and drug delivery agent, including the encapsulation of probiotics. This is important considering the fact that, until recently, encapsulation and coating agents used in the pharmaceutical industry were limited to the use of lactose, a potentially allergenic agent or gelatin. Obtained at a relatively low cost from marine brown algae, this hydrocolloid can also be used as a potential tool in the management of diabetes, not only as an insulin delivery agent but also due to its ability to improve insulin resistance, attenuate chronic inflammation and decrease oxidative stress. In addition, alginate has been recognized as a potential weight loss treatment, as alginate supplementation has been used as an adjunct treatment to energy restriction, to enhance satiety and improve weight loss in obese individuals. Thus, alginate holds the promise of an effective product used in the food industry as well as in the management of metabolic disorders such as diabetes and obesity. This review highlights recent research advances on the characteristics of alginate and brings to the forefront the beneficial aspects of using alginate, from the food industry to the biomedical field.

New Edible Packaging Material with Function in Shelf Life Extension: Applications for the Meat and Cheese Industries

Nowadays, biopolymer films have gained notoriety among the packaging materials. Some studies clearly test their effectiveness for certain periods of time, with applicability in the food industry. This research has been carried out in two directions. Firstly, the development and testing of the new edible material: general appearance, thickness, retraction ratio, color, transmittance, microstructure, roughness, and porosity, as well as mechanical and solubility tests. Secondly, testing of the packaged products-slices of cheese and prosciutto-in the new material and their maintenance at refrigeration conditions for 5 months; thus, the peroxide index, color, and water activity index were evaluated for the packaged products. The results emphasize that the packaging is a lipophilic one and does not allow wetting or any changes in the food moisture. The results indicate the stability of the parameters within three months and present the changes occurring within the fourth and fifth months. Microbiological tests indicated an initial microbial growth, both for cheese slices and ham slices. Time testing indicated a small increase in the total count number over the 5-month period: 23 cfu/g were found of fresh slices of prosciutto and 27 cfu/g in the case of the packaged ones; for slices of cheese, the total count of microorganisms indicated 7 cfu/g in the initial stage and 11 cfu/g after 5 months. The results indicate that the film did not facilitate the growth of the existing microorganisms, and highlight the need to purchase food from safe places, especially in the case of raw-dried products that have not undergone heat treatment, which may endanger the health of the consumer. The new material tested represents a promising substitute for commercial and unsustainable plastic packaging.

The Use of Edible Films Based on Sodium Alginate in Meat Product Packaging: An Eco-Friendly Alternative to Conventional Plastic Materials

The amount of plastics used globally today exceeds a million tonnes annually, with an alarming annual growth. The final result is that plastic packaging is thrown into the environment, and the problem of waste is increasing every year. A real alternative is the use bio-based polymer packaging materials. Research carried out in the laboratory context and products tested at the industrial level have confirmed the success of replacing plastic-based packaging with new, edible or completely biodegradable foils. Of the polysaccharides used to obtain edible materials, sodium alginate has the ability to form films with certain specific properties: resistance, gloss, flexibility, water solubility, low permeability to O2 and vapors, and tasteless or odorless. Initially used as coatings for perishable or cut fresh fruits and vegetables, these sodium alginate materials can be applied to a wide range of foods, especially in the meat industry. Used to cover meat products, sodium alginate films prevent mass loss and degradation of color and texture. The addition of essential oils prevents microbial contamination with Escherichia coli, Salmonella enterica, Listeria monocytogenes, or Botrytis cinerea. The obtained results promote the substitution of plastic packaging with natural materials based on biopolymers and, implicitly, of sodium alginate, with or without other natural additions. These natural materials have become the packaging of the future.