Inhibition of Listeria monocytogenes growth in turkey fillets by alginate edible coating with Trachyspermum ammi essential oil nano-emulsion

Comprehensive Review on the Biocontrol of Listeria monocytogenes in Food Products

Listeria monocytogenes is a foodborne pathogen that causes listeriosis, a group of human illnesses that appear more frequently in countries with better-developed food supply systems. This review discusses the efficacy of actual biocontrol methods combined with the main types of food involved in illnesses. Comments on bacteriophages, lactic acid bacteria, bacteriocins, essential oils, and endolysins and derivatives, as main biological antilisterial agents, are made bearing in mind that, using them, food processors can intervene to protect consumers. Both commercially available antilisterial products and solutions presented in scientific papers for mitigating the risk of contamination are emphasized. Potential combinations between different types of antilisterial agents are highlighted for their synergic effects (bacteriocins and essential oils, phages and bacteriocins, lactic acid bacteria with natural or synthetic preservatives, etc.). The possibility to use various antilisterial biological agents in active packaging is also presented to reveal the diversity of means that food processors may adopt to assure the safety of their products. Integrating biocontrol solutions into food processing practices can proactively prevent outbreaks and reduce the occurrences of L. monocytogenes-related illnesses.

Antibacterial properties of hexanal-chitosan nanoemulsion against Vibrio parahaemolyticus and its application in shelled shrimp preservation at 4 °C

Vibrio parahaemolyticus has been considered as the leading pathogen associated with seafood-borne disease. Hexanal possesses antibacterial property but the hydrophobicity and volatility limit its application. The purpose of this study was to prepare hexanal-chitosan nanoemulsion (HCN), investigate its antibacterial ability against V. parahaemolyticus, and examine the combination of HCN with sodium alginate coating on the quality attributes of shrimp during cold storage. The mean droplet size of HCN fabricated by ultrasonic emulsification was 91.28 nm. HCN showed regular spherical shape and exhibited good centrifugation stability and storage stability at 4 °C. HCN exerted anti-V. parahaemolyticus effect with the minimum inhibitory concentration and minimal bactericidal concentration of both 5 mg/mL. Furthermore, HCN induced morphological changes and destroyed bacterial membrane, resulting in cell death. The results of preservation test showed that HCN alone and its combination with sodium alginate coating effectively retarded the quality deterioration and microbial spoilage of shelled shrimps during refrigerated storage. Comparatively, the combination treatment exhibited better preservation effect. The present study suggested that HCN prepared by ultrasonic emulsification is an effective alternative to control V. parahaemolyticus contamination in seafood and also shows great application potential in the quality maintaining of seafood during cold storage.

Can droplet size influence antibacterial activity in ultrasound-prepared essential oil nanoemulsions?

Essential oil nanoemulsion may have improved antibacterial properties over pure oil and can be used for food preservation. Ultrasonic cavitation is the most common mechanism for producing nanoemulsions, and the impact of processing parameters on droplet properties needs to be elucidated. A systematic literature search was performed in four databases (Science Direct, Web of Science, Scopus and PubMed), and 987 articles were found, 16 of which were eligible for the present study. A meta-analysis was performed to qualitatively assess which process parameters (power, sonication time, essential oil, and tween 80 concentration) can influence the final droplet size and polydispersity and how droplet size is associated with antibacterial activity. We observed that power, essential oil, and tween 80 concentrations added during processing are the critical variables for forming smaller droplets. Ratios of up to 3:1 (surfactant:oil) can produce droplets smaller than 180 nm with antibacterial properties superior to pure oil or isolated compounds. The improved properties of nanoemulsions are associated with the size and chemical composition of the droplet since the proportion of the hydrophobic core (EO) and the hydrophilic outer layer (Tween 80) directly influences the antibacterial mechanism of action.

Polysaccharide-Based Edible Films/Coatings for the Preservation of Meat and Fish Products: Emphasis on Incorporation of Lipid-Based Nanosystems Loaded with Bioactive Compounds

The high water and nutritional contents of meat and fish products make them susceptible to spoilage. Thus, one of the most important challenges faced by the meat industry is extending the shelf life of meat and fish products. In recent years, increasing concerns associated with synthetic compounds on health have limited their application in food formulations. Thus, there is a great need for natural bioactive compounds. Direct use of these compounds in the food industry has faced different obstacles due to their hydrophobic nature, high volatility, and sensitivity to processing and environmental conditions. Nanotechnology is a promising method for overcoming these challenges. Thus, this article aims to review the recent knowledge about the effect of biopolymer-based edible films or coatings on the shelf life of meat and fish products. This study begins by discussing the effect of biopolymer (pectin, alginate, and chitosan) based edible films or coatings on the oxidation stability and microbial growth of meat products. This is followed by an overview of the nano-encapsulation systems (nano-emulsions and nanoliposomes) and the effect of edible films or coatings incorporated with nanosystems on the shelf life of meat and fish products.

Potential of Essential Oils in the Control of Listeria monocytogenes

Listeria monocytogenes is a foodborne pathogen, the causative agent of listeriosis. Infections typically occur through consumption of foods, such as meats, fisheries, milk, vegetables, and fruits. Today, chemical preservatives are used in foods; however, due to their effects on human health, attention is increasingly turning to natural decontamination practices. One option is the application of essential oils (EOs) with antibacterial features, since EOs are considered by many authorities as being safe. In this review, we aimed to summarize the results of recent research focusing on EOs with antilisterial activity. We review different methods via which the antilisterial effect and the antimicrobial mode of action of EOs or their compounds can be investigated. In the second part of the review, results of those studies from the last 10 years are summarized, in which EOs with antilisterial effects were applied in and on different food matrices. This section only included those studies in which EOs or their pure compounds were tested alone, without combining them with any additional physical or chemical procedure or additive. Tests were performed at different temperatures and, in certain cases, by applying different coating materials. Although certain coatings can enhance the antilisterial effect of an EO, the most effective way is to mix the EO into the food matrix. In conclusion, the application of EOs is justified in the food industry as food preservatives and could help to eliminate this zoonotic bacterium from the food chain.

Effect of nanopackaging on the quality of edible mushrooms and its action mechanism: A review

With higher demands for food packaging and the development of nanotechnology, nanopackaging is becoming a research hotspot in the field of food packaging because of its superb preservation effect, and it can effectively resist oxidation and regulates energy metabolism to maintain the quality and prolong the shelf life of mushrooms. Furthermore, under the background of SARS-CoV-2 pandemic, nanomaterials could be a potential tool to prevent virus transmission because of their excellent antiviral activities. However, the investigation and application of nanopackaging are facing many challenges including costs, environmental pollution, poor in-depth genetic research for mechanisms and so on. This article reviews the preservation effect and mechanisms of nanopackaging on the quality of mushrooms and discusses the trends and challenges of using these materials in food packaging technologies with the focus on nanotechnology and based on recent studies.

Fabrication, characterization, and interventions of protein, polysaccharide and lipid-based nanoemulsions in food and nutraceutical delivery applications: A review

The fabrication and application of nanoemulsions for incorporating and delivering diverse bioactive compounds, particularly hydrophobic substances, is becoming an increasing focus of research with the potential to improve the nutritional and health status of individuals. Constant advancements in nanotechnological approaches aid in the creation of nanoemulsions using diverse biopolymers such as proteins, peptides, polysaccharides, and lipids to improve the stability, bioactivity, and bioavailability of active hydrophilic and lipophilic compounds. This article provides a comprehensive overview of various techniques used to create and characterize nanoemulsions as well as theories for understanding their stability. The article also highlights the advancement of nanoemulsions in boosting the bioaccessibility of nutraceuticals to help advance their potential use in various food and pharmaceutical formulations.

Application of alginate polymer films and coatings incorporated with essential oils in foods: a review of recent literature with emphasis on nanotechnology

Food waste is one of the major challenges in food safety and finding a solution for this issue is critically important. Herein, edible films and coatings became attractive for scientists as they can keep food from spoilage. Edible films and coatings can effectively preserve the original quality of food and extend its shelf life. Polysaccharides, including starch and cellulose derivatives, chitosan, alginate and pectin, have been extensively studied as biopackaging materials. One of the most interesting polysaccharides is alginate, which has been used to make edible films and coatings. Incorporating essential oils (EO) in alginate matrices results in an improvement in some properties of the edible packages, such as antioxidant and antimicrobial properties. Additionally, the use of nanotechnology can improve the desirable properties of edible films and coatings. In this article we reviewed the antimicrobial and antioxidant properties of alginate coatings and films and their use in various food products.

Emulsion-Based Coatings for Preservation of Meat and Related Products

One of the biggest challenges faced by the meat industry is maintaining the freshness of meat while extending its shelf life. Advanced packaging systems and food preservation techniques are highly beneficial in this regard. However, the energy crisis and environmental pollution demand an economically feasible and environmentally sustainable preservation method. Emulsion coatings (ECs) are highly trending in the food packaging industry. Efficiently developed coatings can preserve food, increase nutritional composition, and control antioxidants' release simultaneously. However, their construction has many challenges, especially for meat. Therefore, the following review focuses on the essential aspects of developing ECs for meat. The study begins by classifying emulsions based on composition and particle size, followed by a discussion on the physical properties, such as ingredient separation, rheology, and thermal characteristics. Furthermore, it discusses the lipid and protein oxidation and antimicrobial characteristics of ECs, which are necessary for other aspects to be relevant. Lastly, the review presents the limitations of the literature while discussing the future trends. ECs fabricated with antimicrobial/antioxidant properties present promising results in increasing the shelf life of meat while preserving its sensory aspects. In general, ECs are highly sustainable and effective packaging systems for meat industries.

Nanoemulsion-based approach to preserve muscle food: A review with current knowledge

Muscle foods are regarded as nutritionally dense foods while they are prone to spoilage by action of microorganism and oxidation. Recently, the consumer's preference is mostly toward minimally processed foods as well as preserved with natural preservatives. However, natural extract directly to the food matrix has several drawbacks. Hence development and applications of nanoemulsion has gained importance for the preservation of muscle foods to meet consumer requirements with enhanced food safety. Nanoemulsion utilizes natural extracts at much lower concentration with higher preservative abilities over original components. Nanoemulsions offer protection to the active component from degradation and ensure longer bioavailability. Novel techniques used for formulation of nanoemulsion provide stability to the emulsion with desirable qualities to improve their impacts. The application of nanoemulsion is known to enhance the preservative action of nanoemulsions by improving the microbial safety and oxidative stability in nanoform. This review provides recent updates on different methods used for formulation of nanoemulsions from different sources. Besides, successful application of nanoemulsion derived using natural agents for muscle food preservation and shelf life extension are reviewed. Thus, the application of nanoemulsion to extend shelf life and maintain quality is suggested for muscle foods.

Inhibitory Effect of Sodium Alginate Nanoemulsion Coating Containing Myrtle Essential Oil (Myrtus communis L.) on Listeria monocytogenes in Kasar Cheese

The present study aimed to characterize the physical properties of nanoemulsion-based sodium alginate edible coatings containing myrtle (Myrtus communis L.) essential oil and to determine its inhibitory effects on Listeria monocytogenes in fresh Kasar cheese during the 24-day storage at 4 °C. The GC-MS analysis showed that the main components of myrtle essential oil were 1,8-cineol (38.64%), α-pinene (30.19%), d-limonene (7.51%), and α-ocimene (6.57%). Myrtle essential oil showed an inhibitory effect on all tested L. monocytogenes strains and this effect significantly increased after ultrasonication. Minimum inhibitory and minimum bactericidal concentrations of myrtle essential oil nanoemulsion were found to be 4.00-4.67 mg/mL and 5.00-7.33 mg/mL, respectively. The antibacterial activity of myrtle essential oil nanoemulsion against L. monocytogenes was confirmed by the membrane integrity and FESEM analyses. Nanoemulsion coatings containing myrtle essential oil showed antibacterial activity against L. monocytogenes with no adverse effects on the physicochemical properties of cheese samples. Nanoemulsion coatings containing 1.0% and 2.0% myrtle essential oil reduced the L. monocytogenes population in cheese during the storage by 0.42 and 0.88 log cfu/g, respectively. These results revealed that nanoemulsion-based alginate edible coatings containing myrtle essential oil have the potential to be used as a natural food preservative.

Structures, Properties and Applications of Alginates

Alginate is a hydrocolloid from algae, specifically brown algae, which is a group that includes many of the seaweeds, like kelps and an extracellular polymer of some bacteria. Sodium alginate is one of the best-known members of the hydrogel group. The hydrogel is a water-swollen and cross-linked polymeric network produced by the simple reaction of one or more monomers. It has a linear (unbranched) structure based on d-mannuronic and l-guluronic acids. The placement of these monomers depending on the source of its production is alternating, sequential and random. The same arrangement of monomers can affect the physical and chemical properties of this polysaccharide. This polyuronide has a wide range of applications in various industries including the food industry, medicine, tissue engineering, wastewater treatment, the pharmaceutical industry and fuel. It is generally recognized as safe when used in accordance with good manufacturing or feeding practice. This review discusses its application in addition to its structural, physical, and chemical properties.

Application of Nanotechnology to Improve the Performance of Biodegradable Biopolymer-Based Packaging Materials

There is great interest in developing biodegradable biopolymer-based packaging materials whose functional performance is enhanced by incorporating active compounds into them, such as light blockers, plasticizers, crosslinkers, diffusion blockers, antimicrobials, antioxidants, and sensors. However, many of these compounds are volatile, chemically unstable, water-insoluble, matrix incompatible, or have adverse effects on film properties, which makes them difficult to directly incorporate into the packaging materials. These challenges can often be overcome by encapsulating the active compounds within food-grade nanoparticles, which are then introduced into the packaging materials. The presence of these nanoencapsulated active compounds in biopolymer-based coatings or films can greatly improve their functional performance. For example, anthocyanins can be used as light-blockers to retard oxidation reactions, or they can be used as pH/gas/temperature sensors to produce smart indicators to monitor the freshness of packaged foods. Encapsulated botanical extracts (like essential oils) can be used to increase the shelf life of foods due to their antimicrobial and antioxidant activities. The resistance of packaging materials to external factors can be improved by incorporating plasticizers (glycerol, sorbitol), crosslinkers (glutaraldehyde, tannic acid), and fillers (nanoparticles or nanofibers). Nanoenabled delivery systems can also be designed to control the release of active ingredients (such as antimicrobials or antioxidants) into the packaged food over time, which may extend their efficacy. This article reviews the different kinds of nanocarriers available for loading active compounds into these types of packaging materials and then discusses their impact on the optical, mechanical, thermal, barrier, antioxidant, and antimicrobial properties of the packaging materials. Furthermore, it highlights the different kinds of bioactive compounds that can be incorporated into biopolymer-based packaging.

Low-dose gamma irradiation and pectin biodegradable nanocomposite coating containing curcumin nanoparticles and ajowan (Carum copticum) essential oil nanoemulsion for storage of chilled lamb loins

The current investigation assessed the effect of pectin (PE) biodegradable nanocomposite coating containing curcumin nanoparticles (CNP) and ajowan (Carum copticum) essential oil nanoemulsion (ANE) combined with low-dose gamma irradiation on microbial, physiochemical, and sensorial qualities of lamb loins during refrigeration conditions. Active coating combined with gamma irradiation reduced the count number of mesophilic and psychrotrophic bacteria, lactic acid bacteria, Enterobacteriaceae; and minimized lipid and protein oxidation changes, total volatile basic nitrogen content, met-myoglobin formation, and color deterioration in the loin samples. The increased shelf-life of lamb loins up to 25 days compared with 5 days assigned for the control group can be associated with the application of ionizing radiation and edible PE coating containing CNP and ANE, which might be due to the synergistic or additive effects of treatments. Overall, as an effective preservation technique, a combination of PE + CNP + ANE and irradiation can be recommended for prolonging the shelf-life of lamb loins during refrigerated storage.

Nanotechnology as a Processing and Packaging Tool to Improve Meat Quality and Safety

Nanoparticles are gaining momentum as a smart tool towards a safer, more cost-effective and sustainable food chain. This study aimed to provide an overview of the potential uses, preparation, properties, and applications of nanoparticles to process and preserve fresh meat and processed meat products. Nanoparticles can be used to reinforce the packaging material resulting in the improvement of sensory, functional, and nutritional aspects of meat and processed meat products. Further, these particles can be used in smart packaging as biosensors to extend the shelf-life of fresh and processed meat products and also to monitor the final quality of these products during the storage period. Nanoparticles are included in product formulation as carriers of health-beneficial and/or functional ingredients. They showed great efficiency in encapsulating bioactive ingredients and preserving their properties to ensure their functionality (e.g., antioxidant and antimicrobial) in meat products. As a result, nanoparticles can efficiently contribute to ensuring product safety and quality whilst reducing wastage and costs. Nevertheless, a wider implementation of nanotechnology in meat industry is highly related to its economic value, consumers' acceptance, and the regulatory framework. Being a novel technology, concerns over the toxicity of nanoparticles are still controversial and therefore efficient analytical tools are deemed crucial for the identification and quantification of nanocomponents in meat products. Thus, migration studies about nanoparticles from the packaging into meat and meat products are still a concern as it has implications for human health associated with their toxicity. Moreover, focused economic evaluations for implementing nanoparticles in meat packaging are crucial since the current literature is still scarce and targeted studies are needed before further industrial applications.