Development and characterization of pectin films activated by nanoemulsion and Pickering emulsion stabilized marjoram (Origanum majorana L.) essential oil

Structural characterization of modified whey protein isolates using cold plasma treatment and its applications in emulsion oleogels

Cold plasma as a green and expeditious tool was used to modify whey protein isolate (WPI) in order to improve its emulsion capability. The emulsion-based oleogels with antibacterial functions were then constructed using the modified WPI. The modified WPI treated with cold plasma under 10 s at 50 W power significantly lowered the oil-water interface tension. Meanwhile, the fluorescence intensity and the α-helix content of WPI reduced with the cold plasma treatment. It is noted that SEM results showed that the treated WPI had more regular dendritic structures. Such modified WPI was applied to construct oleogels loaded with thyme essential oil and coconut oil, which showed a porous uniform network structure and excellent antimicrobial activities against E.coli. As a proof of concept, this study demonstrated cold plasma could be as a new facile tool to modify food-sourced proteins and expected to enlarge their applications in oleogel productions.

Advances in biopolymeric active films incorporated with emulsified lipophilic compounds: a review

The attention towards active films has increased due to consumer demand for high-quality foods without chemical additives. Active biopolymer-based films have shown great potential for active films by impacting food safety, acting as the carriers of various natural antioxidant and antimicrobial compounds, and decreasing environmental pollution from petrol-derived packaging materials. However, there is a wide range of challenges concerning the different characteristics of biopolymers and plasticizers, often hygroscopic/hydrophilic, compared to numerous lipophilic bioactive compounds. Therefore, recent studies have focused on applying oil-in-water emulsion-based systems to enhance the lipophilic bioactive compounds' dispersibility into the film matrix, improving their performance. It is worth emphasizing that resulting complex systems give rise to new challenges such as (i) dispersion technology of the bioactive compounds with minimum adverse effects on its bioactivities, (ii) interactions between different components of the active films, giving rise to new physicochemical properties, and (iii) the change of the diffusion properties of bioactive compounds into the active films, resulting in different release properties. These challenges are profound and critically discussed in this review, as well as the encapsulation techniques employed in preparing emulsions loaded with lipophilic bioactive compounds for the active film development. An outlook of future directions in the research, development, and application of these active films are given.

Advanced biomaterials for sustainable applications in the food industry: Updates and challenges

Maintaining the safety and quality of food are major concerns while developing biomaterial based food packaging. It offers a longer shelf-life as well as protection and quality control to the food based on international standards. Nano-biotechnology contributes to a far extent to make advanced packaging by developing multifunctional biomaterials for potential applications providing smarter materials to consumers. Applications of nano-biocomposites may thus help to deliver enhanced barrier, mechanical strength, antimicrobial and antioxidant properties to novel food packaging materials. Starch derived bioplastics, polylactic acid and polyhydroxybutyrate are examples of active bioplastics currently in the food packaging sector. This review discusses the various types of biomaterials that could be used to improve future smarter food packaging, as well as biomaterials' potential applications as food stabilizers, pathogen control agents, sensors, and edible packaging materials. The regulatory concerns related to the use of biomaterials in food packaging and commercially available biomaterials in different fields are also discussed. Development of novel biomaterials for different food packaging applications can therefore guarantee active food packaging in future.

Effective strategies of sustained release and retention enhancement of essential oils in active food packaging films/coatings

Due to environmental issues caused by plastic packaging and growing consumer demand for fresh and safe food, there is a growing interest in antibacterial active food packaging films/coatings containing plant essential oils (EO). For the effective use of EO-incorporated active films/coatings, EO must be effectively integrated encapsulated in active films/coatings, and the integrated encapsulated EO must be released from active films/coatings slowly during storage to exhibit antibacterial effects more durable. Recently, several promising strategies have been proposed to improve the sustained release and retention enhancement of EO in active films/coatings, including particle encapsulation, nanoemulsion, Pickering emulsions, multilayer system, and electrospinning technology. This article reviewed the latest technologies of sustained release and retention enhancement strategies for encapsulating EO in active films/coatings. The advantages and disadvantages of these sustained release and retention enhancement strategies and their practical applications in food preservation are also introduced.

Smart and Active Food Packaging: Insights in Novel Food Packaging

The demand for more healthy foods with longer shelf life has been growing. Food packaging as one of the main aspects of food industries plays a vital role in meeting this demand. Integration of nanotechnology with food packaging systems (FPSs) revealed promising promotion in foods’ shelf life by introducing novel FPSs. In this paper, common classification, functionalities, employed nanotechnologies, and the used biomaterials are discussed. According to our survey, FPSs are classified as active food packaging (AFP) and smart food packaging (SFP) systems. The functionality of both systems was manipulated by employing nanotechnologies, such as metal nanoparticles and nanoemulsions, and appropriate biomaterials like synthetic polymers and biomass-derived biomaterials. “Degradability and antibacterial” and “Indicating and scavenging” are the well-known functions for AFP and SFP, respectively. The main purpose is to make a multifunctional FPS to increase foods’ shelf life and produce environmentally friendly and smart packaging without any hazard to human life.

Advantages and challenges of Pickering emulsions applied to bio-based films: a mini-review

The strategy of adding hydrophobic compounds to bio-based films (usually based on hydrophilic matrices), forming films containing emulsions, is a technique that has been used to improve some physical properties (such as reducing water solubility and water vapor permeability) and / or to impart properties, such as antioxidant and antimicrobial effects by carrying hydrophobic active components that would otherwise be insoluble in hydrophilic matrices. Although Pickering emulsions have been reported as presenting greater stability when compared with surfactant-stabilized emulsions, little is known about the drying stability of Pickering emulsions (which is important for film applications). Anyway, several studies have indicated that Pickering emulsions are interesting systems to improve the water vapor barrier properties of bio-based films and coatings, and to act as carriers of active hydrophobic components. On the other hand, the tensile properties of those films are usually impaired by the presence of Pickering emulsions. The objective of this review is to present recent developments and future perspectives in bio-based films loaded with Pickering emulsions. © 2020 Society of Chemical Industry.

Mathematical modeling of cinnamon (Cinnamomum verum) bark oil release from agar/PVA biocomposite film for antimicrobial food packaging: The effects of temperature and relative humidity

Antimicrobial biocomposite films were prepared using agar (AG) and polyvinyl alcohol (PVA) as polymer matrix materials and cinnamon bark oil (CBO) as antimicrobial agent. AG and PVA were blended with different mixing ratios. The addition of AG improved the overall water resistance properties of the composite films. To evaluate the effects of temperature and relative humidity (RH) on the release kinetics of CBO from films, CBO release kinetics were analyzed under the 9 combinations of temperature and RH. Then, mathematical modeling of obtained data was conducted using Peleg, Ritger-Peppas, and Peppas-Sahlin models to investigate the release mechanisms of CBO. Consequently, the CBO release rate proportionally increased with the temperature and RH, with the RH being the main factor affecting the release behavior of CBO. In vitro antimicrobial activity tests against gram-positive and gram-negative bacteria showed that the developed composite films have high applicability as an antimicrobial food packaging material.

Development of active packaging films based on chitosan and nano-encapsulated luteolin

Luteolin is a flavone with potent antioxidant and antimicrobial activities. In this study, luteolin was encapsulated in oil-in-water nanoemulsions that were emulsified by glycerol monooleate and Tween 20. Results showed 68 mg luteolin-loaded nanoemulsions had the highest stability (zeta potential of -39.8 mV) and encapsulation efficiency (89.52%). Then, active packaging films were developed by incorporating free or nano-encapsulated luteolin into chitosan-based matrix. The microstructure, physical and functional properties of CS film containing free luteolin (CS-LL) or nano-encapsulated luteolin (CS-LLNEs) were compared. Different from CS film, CS-LL and CS-LLNEs films had compact inner microstructure and strengthened intermolecular interactions. Moreover, CS-LLNEs film was more homogenous and compact than CS-LL film. As a result, CS-LLNEs film presented higher water vapor and oxygen barrier abilities and mechanical properties in comparison with CS-LL film. In addition, CS-LLNEs film showed slower release rate of luteolin in 95% ethanol (fatty food stimulant) as compared with CS-LL film. The controlled release of luteolin from film matrix could guarantee CS-LLNEs film to exert antioxidant activity up to 10 days. Our results suggest CS-LLNEs film can be developed as an emerging active packaging material that has potential applications in food industry.

Preparation and characterization of clove essential oil loaded nanoemulsion and pickering emulsion activated pullulan-gelatin based edible film

The clove essential oil (CEO) loaded nano and pickering emulsions prepared with Tween 80 and whey protein isolate/inulin mixture, respectively were incorporated into pullulan-gelatin film base fluid at three levels (0.2%, 0.4%, and 0.6%). The droplet sizes of NE and PE loaded with CEO were 15.93 nm and 266.9 nm, respectively. The PDI of CEOs with stable NE and PE were 0.262 and 0.259, respectively. Our results showed the improved compatibility between pullulan-gelatin and essential oil-loaded nanocarriers. The active film composed of PE carrier had the structural characteristics of high density, low water content, and low permeability, thus exhibiting excellent mechanical properties, water barrier properties, and appreciable antioxidant activities. Compared with NE, it was found that the CEO-loaded PE showed slow-release profile in the film sample. The prepared active film containing PE possessed a great potential to be used as effective and natural alternatives for active food packaging.

Progresses in Food Packaging, Food Quality, and Safety-Controlled-Release Antioxidant and/or Antimicrobial Packaging

Food packaging is designed to protect foods, to provide required information about the food, and to make food handling convenient for distribution to consumers. Packaging has a crucial role in the process of food quality, safety, and shelf-life extension. Possible interactions between food and packaging are important in what is concerning food quality and safety. This review tries to offer a picture of the most important types of active packaging emphasizing the controlled/target release antimicrobial and/or antioxidant packaging including system design, different methods of polymer matrix modification, and processing. The testing methods for the appreciation of the performance of active food packaging, as well as mechanisms and kinetics implied in active compounds release, are summarized. During the last years, many fast advancements in packaging technology appeared, including intelligent or smart packaging (IOSP), (i.e., time-temperature indicators (TTIs), gas indicators, radiofrequency identification (RFID), and others). Legislation is also discussed.

Fortification of edible films with bioactive agents: a review of their formation, properties, and application in food preservation

Biodegradable films constructed from food ingredients are being developed for food coating and packaging applications to create more sustainable and environmentally friendly alternatives to plastics and other synthetic film-forming materials. In particular, there is a focus on the creation of active packaging materials from natural ingredients, especially plant-based ones. The film matrix is typically constructed from film-forming food components, such as proteins, polysaccharides and lipids. These matrices can be fortified with active ingredients, such as antioxidants and antimicrobials, so as to enhance their functional properties. Edible active films must be carefully designed to have the required optical, mechanical, barrier, and preservative properties needed for commercial applications. This review focuses on the fabrication, properties, and functional performance of edible films constructed from natural active ingredients. It provides an overview of the type of active ingredients that can be used, how they interact with the film matrix, how they migrate through the films, and how they are released. It also discusses the potential application of these active films for food preservation. Finally, future trends are highlighted and areas where further research are required are discussed.

Pectin modified with phenolic acids: Evaluation of their emulsification properties, antioxidation activities, and antibacterial activities

Three phenolic acids including p-hydroxybenzoic acid (PHBA), 3,4-dihydroxybenzoic acid, (DHBA), and gallic acid (GA) were grafted onto native pectin (Na-Pe) through enzymatic method. Ultraviolet-visible spectrometry, Fourier transform infrared spectroscopy, and ¹H NMR analyses were used to explore the reaction mechanism. Results indicated that the p-hydroxyl of the phenolic acids reacted with the methoxycarbonyl of pectin through transesterification, and a covalent connection was formed. The phenolic acid contents of PHBA modified pectin (Ph-Pe), DHBA modified pectin (Dh-Pe), and GA modified pectin (Ga-Pe) were 20.18%, 18.87%, and 20.32%, respectively. After acylation with phenolic acids, the 1,1-diphenyl-2-picryl hydrazine clearance of pectin changed from 7.68% (Na-Pe) to 6.88% (Ph-Pe), 40.80% (Dh-Pe), and 90.30% (Ga-Pe), whereas its inhibition ratio of pectin increased from 3.11% (Na-Pe) to 35.02% (Ph-Pe), 66.36% (Dh-Pe), and 77.89% (Ga-Pe). Moreover, compared with Na-Pe, modified pectins exhibited better emulsification properties and stronger antibacterial activities against both Escherichia coli and Staphylococcus aureus.

Traditional use, phytochemistry, toxicology, and pharmacology of Origanum majorana L

ETHNOPHARMACOLOGICAL RELEVANCE

Origanum majorana L., is an aromatic and medicinal plant distributed in different parts of Mediterranean countries. This species is widely used in traditional medicine for the treatment of many diseases such as allergies, hypertension, respiratory infections, diabetes, stomach pain, and intestinal antispasmodic.

AIM OF THE REVIEW

This work reports previous studies on O. majorana concerning its taxonomy, botanical description, geographical distribution, traditional use, bioactive compounds, toxicology, and biological effects.

MATERIALS AND METHODS

Different scientific data bases such as Web of Science, Scopus, Wiley Online, SciFinder, Google Scholar, PubMed, ScienceDirect, and SpringerLink were consulted to collect data about O. majorana. The presented data emphasis bioactive compounds, traditional uses, toxicological investigations, and biological activities of O. majorana.

RESULTS

The findings of this work marked an important correlation between the traditional use of O. majorana as an anti-allergic, antihypertensive, anti-diabetic agent, and its biological effects. Indeed, pharmacological investigations showed that essential oils and extracts from O. majorana exhibit different biological properties, particularly; antibacterial, antifungal, antioxidant, antiparasitic, antidiabetic, anticancer, nephrotoxicity protective, anti-inflammatory, analgesic and anti-pyretic, hepatoprotective, and antimutagenic effects. Toxicological evaluation confirmed the safety and innocuity of this species and supported its medicinal uses. Several bioactive compounds belonging to different chemical family such as terpenoids, flavonoids, and phenolic acids were also identified in O. majorana.

CONCLUSIONS

The results suggest that the pharmacological properties of O. majorana confirm its traditional uses. Indeed, O. majorana essential oils showed remarkable antimicrobial, antioxidant, anticancer, anti-inflammatory, antimutagenic, nephroprotective, and hepatoprotective activities. However, further investigations regarding the evaluation of molecular mechanisms of identified compounds against human cancer cell lines, inflammatory process, and microbial infections are needed to validate pharmacodynamic targets. The toxicological investigation of O. Majorana confirmed its safety and therefore encouraged pharmacokinetic evaluation tests to validate its bioavailability.

Nano-technological approaches for plant and marine-based polysaccharides for nano-encapsulations and their applications in food industry

Novel food preservation methods, along with preservatives have been employed to prevent food products from spoilage. There is an increasing demand to substitute synthetic preservatives with natural bioactive compounds since they are safe and environmentally friendly. Bioactive compounds with functional and therapeutic properties are found in foods and have also beneficial physiological and immunological health effects. However, there are some issues associated with bioactive compounds, such as low stability, solubility, and permeability. Encapsulation techniques, especially nano-encapsulation, are a promising technique to overcome these restrictions. A range of the plants' constituents can be converted into bio-nanomaterials. Major plant constituents are polysaccharides which have good biocompatibility properties and therapeutic activities, such as antioxidant, antiviral, anti-inflammatory, anti-allergic, and anti-tumor. Among plant and marine-based polysaccharides, cellulose, starch, alginates, chitosan, and carrageenans have been used as carrier materials to preserve core material. Moreover, many studies indicated that favorable sources such as plant and marine based polysaccharides are emerging. This chapter will cover plant and marine-based polysaccharides for nano-encapsulation and their application in the food industry.

The effect of Macro and Nano-emulsions of cinnamon essential oil on the properties of edible active films

The effect of Nano-emulsion (NE) and Macro-emulsion (ME) of cinnamon essential oil (CEO) on the properties of carboxymethyl cellulose (CMC)-based films was investigated. MEs (diameters of 242-362 nm) and NEs (diameters of 59-80 nm) of CEO were produced through Ultra-Turrax and Ultrasonication, respectively. The scanning electron microscopy (SEM) and atomic force microscopy (AFM) images showed different morphologies in the films containing ME and NE, also a denser and more uniform microstructure was observed in the NE films in comparison with the ME ones. The higher stability of NE in the CMC matrix, increased the thickness of the resulted films. The water vapor permeability (WVP) was increased from 2.59 × 10-9 g/ms Pa in the control film to 4.43 × 10-9 g/m s Pa in the ME film, and decreased to 1.80 × 10-9 g/ms Pa in the NE film. Adding CEO led to more flexible films with enhanced strain at break (SAB) from 53.56% in the control film to 80% and 94.77% in the ME and NE films, respectively. The antifungal indices against A. niger and M. racemous were 14.16% and 20.82% in the ME films, and were improved to 18.81% and 25% in the NE ones.

Innovations in Smart Packaging Concepts for Food: An Extensive Review

Innovation in food packaging is mainly represented by the development of active and intelligent packing technologies, which offer to deliver safer and high-quality food products. Active packaging refers to the incorporation of active component into the package with the aim of maintaining or extending the product quality and shelf-life. The intelligent systems are able to monitor the condition of packaged food in order to provide information about the quality of the product during transportation and storage. These packaging technologies can also work synergistically to yield a multipurpose food packaging system. This review is a critical and up-dated analysis of the results reported in the literature about this fascinating and growing field of research. Several aspects are considered and organized going from the definitions and the regulations, to the specific functions and the technological aspects regarding the manufacturing technologies, in order to have a complete overlook on the overall topic.

Pectin-Based Films with Cocoa Bean Shell Waste Extract and ZnO/Zn-NPs with Enhanced Oxygen Barrier, Ultraviolet Screen and Photocatalytic Properties

In this work, pectin-based active films with a cocoa bean shell extract, obtained after waste valorisation of residues coming from the chocolate production process, and zinc oxide/zinc nanoparticles (ZnO/Zn-NPs) at different concentrations, were obtained by casting. The effect of the active additive incorporation on the thermal, barrier, structural, morphological and optical properties was investigated. Moreover, the photocatalytic properties of the obtained films based on the decomposition of methylene blue (MB) in aqueous solution at room temperature were also studied. A significant increase in thermal and oxidative stability was obtained with the incorporation of 3 wt% of ZnO/Zn-NPs compared to the control film. The addition of 5 wt% cocoa bean shell extract to pectin significantly affected the oxygen barrier properties due to a plasticizing effect. In contrast, the addition of ZnO/Zn-NPs at 1 wt% to pectin caused a decrease in oxygen transmission rate per film thickness (OTR.e) values of approximately 50% compared to the control film, resulting in an enhanced protection against oxidation for food preservation. The optical properties were highly influenced by the incorporation of the natural extract but this effect was mitigated when nanoparticles were also incorporated into pectin-based films. The addition of the extract and nanoparticles resulted in a clear improvement (by 98%) in UV barrier properties, which could be important for packaged food sensitive to UV radiation. Finally, the photocatalytic activity of the developed films containing nanoparticles was demonstrated, showing photodegradation efficiency values of nearly 90% after 60 min at 3 wt% of ZnO/Zn-NPs loading. In conclusion, the obtained pectin-based bionanocomposites with cocoa bean shell waste extract and zinc oxide/zinc nanoparticles showed great potential to be used as active packaging for food preservation.

Methods of Incorporating Plant-Derived Bioactive Compounds into Films Made with Agro-Based Polymers for Application as Food Packaging: A Brief Review

Plastic, usually derived from non-renewable sources, is among the most used materials in food packaging. Despite its barrier properties, plastic packaging has a recycling rate below the ideal and its accumulation in the environment leads to environmental issues. One of the solutions approached to minimize this impact is the development of food packaging materials made from polymers from renewable sources that, in addition to being biodegradable, can also be edible. Different biopolymers from agricultural renewable sources such as gelatin, whey protein, starch, chitosan, alginate and pectin, among other, have been analyzed for the development of biodegradable films. Moreover, these films can serve as vehicles for transporting bioactive compounds, extending their applicability as bioactive, edible, compostable and biodegradable films. Biopolymer films incorporated with plant-derived bioactive compounds have become an interesting area of research. The interaction between environment-friendly biopolymers and bioactive compounds improves functionality. In addition to interfering with thermal, mechanical and barrier properties of films, depending on the properties of the bioactive compounds, new characteristics are attributed to films, such as antimicrobial and antioxidant properties, color and innovative flavors. This review compiles information on agro-based biopolymers and plant-derived bioactive compounds used in the production of bioactive films. Particular emphasis has been given to the methods used for incorporating bioactive compounds from plant-derived into films and their influence on the functional properties of biopolymer films. Some limitations to be overcome for future advances are also briefly summarized. This review will benefit future prospects for exploring innovative methods of incorporating plant-derived bioactive compounds into films made from agricultural polymers.

Aquatic polymer-based edible films of fish gelatin crosslinked with alginate dialdehyde having enhanced physicochemical properties

Fish-derived gelatin (FG), a raw material for edible films, has recently been spotlighted as an alternative source of mammalian gelatin. However, its low stability under moisture conditions and weak mechanical properties limit its application. In this study, a water-stable and mechanically robust FG film was prepared using alginate dialdehyde (ADA) as an eco-friendly crosslinking agent. The crosslinking process of FG with ADA was easily recognized by the change in the color of the FG/ADA composite film, and the browning index of the FG/ADA film could be correlated well with the actual crosslinking degree. The mechanical strength and Young's modulus of the FG/ADA composite film increased significantly with an increase in the content of the ADA crosslinker. In the case of FG/ADA10, the tensile strength and Young's modulus increased by 400 and 600 %, respectively, compared to those of FG. Remarkably, the FG-ADA crosslinking process greatly decreased the vulnerability of FG in moisture environments. Consequently, the FG/ADA10 film remained stable for 30 days under wet environment. In addition, the FG-ADA crosslinking process could enhance the antioxidative capacity of the FG/ADA edible film. According to this study, FG/ADA composite films fabricated in an effective manner using polymers derived from aquatic species like gelatin from fish and ADA from algae could have practical applications in the edible film-based packaging industry.

Antimicrobial Activities of Starch-Based Biopolymers and Biocomposites Incorporated with Plant Essential Oils: A Review

Recently, many scientists and polymer engineers have been working on eco-friendly materials for starch-based food packaging purposes, which are based on biopolymers, due to the health and environmental issues caused by the non-biodegradable food packaging. However, to maintain food freshness and quality, it is necessary to choose the correct materials and packaging technologies. On the other hand, the starch-based film’s biggest flaws are high permeability to water vapor transfer and the ease of spoilage by bacteria and fungi. One of the several possibilities that are being extensively studied is the incorporation of essential oils (EOs) into the packaging material. The EOs used in food packaging films actively prevent inhibition of bacteria and fungi and have a positive effect on food storage. This work intended to present their mechanical and barrier properties, as well as the antimicrobial activity of anti-microbacterial agent reinforced starch composites for extending product shelf life. A better inhibition of zone of antimicrobial activity was observed with higher content of essential oil. Besides that, the mechanical properties of starch-based polymer was slightly decreased for tensile strength as the increasing of essential oil while elongation at break was increased. The increasing of essential oil would cause the reduction of the cohesion forces of polymer chain, creating heterogeneous matrix and subsequently lowering the tensile strength and increasing the elongation (E%) of the films. The present review demonstrated that the use of essential oil represents an interesting alternative for the production of active packaging and for the development of eco-friendly technologies.

Development and Characterization of Citrus Junos Pomace Pectin Films Incorporated With Rambutan (Nephelium Lappaceum) Peel Extract

New packaging materials using biopolymers have been studied to substitute synthetic packaging materials that lead to environmental pollution. In this study, a new biodegradable packaging material was developed using the pectin extracted from Citrus junos pomace, which is considered a food processing byproduct. Rambutan peel extract (RPE), at different concentrations (0.25%, 0.5%, and 1.0%), was added as an active material, and the functional properties of the C. junos pectin (CJP) films were evaluated. The incorporation of RPE enhanced the extensibility of the CJP films and their light-blocking ability by decreasing light transmittance. As the concentration of RPE increased, antioxidant activities of the CJP films increased, along with an increase in total phenolic content. Subsequently, the CJP prepared in this study can be used as a low-cost active biodegradable film material, and RPE can be added as a natural antioxidant for the CJP films to confer antioxidant activity.

Food-Grade Pickering Emulsions: Preparation, Stabilization and Applications

In recent years, Pickering emulsions have emerged as a new method and have attracted much attention in the fields of food sciences. Unlike conventional emulsions, Pickering emulsions are stabilized by solid particles, which can irreversibly adsorb on the oil-water interface to form a dense film to prevent the aggregation of droplets. The research and development of food-grade solid particles are increasingly favored by scientific researchers. Compared with conventional emulsions, Pickering emulsions have many advantages, such as fewer using amounts of emulsifiers, biocompatibility and higher safety, which may offer feasibility to have broad application prospects in a wide range of fields. In this article, we review the preparation methods, stabilization mechanism, degradation of Pickering emulsions. We also summarize its applications in food sciences in recent years and discuss its future prospects and challenges in this work.

A review on techniques utilized for design of controlled release food active packaging

Active packaging (AP) is a new class of innovative food packaging, containing bioactive compounds, is able to maintain the quality of food and extend its shelf life by releasing active agent during storage. The main challenge in designing the AP system is slowing the release rate of active compounds for its prolonged activity. Controlled-release active packaging (CRP) is an innovative technology that provides control in the release of active compounds during storage. Various approaches have been proposed to design CRP. The purpose of this review was to gather and present the strategies utilized for release controlling of active compounds from food AP systems. The chemical modification of polymers, the preparation of multilayer films and the use of cross-linking agents are some methods tried in the last decades. Other approaches use molecular complexes and irradiation treatments. Micro- or nano-encapsulation of active compounds and using nano-structured materials in the AP film matrix are the newest techniques used for the preparation of CRP systems. The action mechanism for each technique was described and an effort was made to highlight representative published papers about each release controlling approach. This review will benefit future prospects of exploring other innovative release controlling methods in food CRP.

Multifunctional betanin nanoliposomes-incorporated gelatin/chitosan nanofiber/ZnO nanoparticles nanocomposite film for fresh beef preservation

The objective of this study was to fabricate betanin nanoliposomes incorporated gelatin/chitosan nanofiber/ZnO nanoparticles bionanocomposite film (G/CH NF/ZnO NPs/B NLPs) and investigate its effects on the preservation of fresh beef. The scanning electron microscopy image of nanocomposite film displayed a good inter-connective porous morphology. Fourier transform infrared and X-ray diffraction analysis confirmed the formation of new hydrogen bonds and enhanced crystallinity through the addition of CH NF, ZnO NPs, and B NLPs. The G/CH NF/ZnO NPs/B NLPs film exhibited satisfactory mechanical properties and high surface hydrophobicity (water contact angle = 92.49 ± 3.71°). The incorporation of ZnO NPs and B NLPs in the nanocomposite film provided high antibacterial activity and DPPH inhibition activity (53.02 ± 3.26%). The growth of inoculated bacteria, lipid oxidation, and the changes in the pH and color quality of the beef samples were controlled by packaging with the fabricated film. In conclusion, the G/CH NF/ZnO NPs/B NLPs nanocomposite has a high potential for meat preservation.

Antimicrobial-loaded nanocarriers for food packaging applications

Increasing the demands of consumers for organic and safer foods has led to applying new technologies for food preservation. Active packaging (AP) containing natural antimicrobial agents is a good candidate for promoting the shelf life of food products. The efficiency of AP has been enhanced through nanoencapsulation methods, in which antimicrobial-loaded nanocarriers could provide a controlled release of antimicrobial active packaging for keeping the quality of foods during storage. The main objective of this review is to introduce common methods for designing novel encapsulation delivery systems offering controlled release of antimicrobials in the AP systems. The common nanocarriers for enveloping antimicrobial agents are described and the current state of art in the application of nanoencapsulated antimicrobials in development of antimicrobial APs have been summarized and tabulated. Incorporation of a carrier loaded with natural antimicrobial agents is the most effective method for developing AP in the food packaging sector which has become possible by using nanoencapsulated antimicrobials in films or coating structures, instead of using their free form. Nanoencapsulation approaches provide many advantages including protection against environmental stresses, release control, and improving the solubility and absorption of natural antimicrobials in AP, which are the main achievements overcoming the barriers for using natural antimicrobials in food packaging.

Encapsulation Systems for Antimicrobial Food Packaging Components: An Update

Antimicrobially active packaging has emerged as an effective technology to reduce microbial growth in food products increasing both their shelf-life and microbial safety for the consumer while maintaining their quality and sensorial properties. In the last years, a great effort has been made to develop more efficient, long-lasting and eco-friendly antimicrobial materials by improving the performance of the incorporated antimicrobial substances. With this purpose, more effective antimicrobial compounds of natural origin such as bacteriocins, bacteriophages and essential oils have been preferred over synthetic ones and new encapsulation strategies such as emulsions, core-shell nanofibres, cyclodextrins and liposomes among others, have been applied in order to protect these antimicrobials from degradation or volatilization while trying to enable a more controlled release and sustained antimicrobial action. On that account, this article provides an overview of the types of antimicrobials agents used and the most recent trends on the strategies used to encapsulate the antimicrobial agents for their stable inclusion in the packaging materials. Moreover, a thorough discussion regarding the benefits of each encapsulation technology as well as their application in food products is presented.