Shelf-life extension and quality attributes of sauced silver carp fillet: A comparison among direct addition, edible coating and biodegradable film

Current trends and perspectives on the color of fish during low-temperature preservation: A focus on evaluation methods, discoloration mechanism, and protection methods

The color of fish during low-temperature preservation is one of the most important sensory indicators of their edible quality and shelf-life. This present review provides an in-depth look at color evaluation methods, including sensory, physical, chemical, and new color evaluation techniques. The key factors involved in discoloration of fish are elucidated in terms of major external factors such as temperature, time and processing methods, as well as internal factors such as myoglobin and lipid oxidation, ice crystal growth, and mitochondrial characteristics involved in the three major components of fish (moisture, proteins, and lipids). Meanwhile, the two most widely used methods reviewed in this paper: improved packaging methods and the addition of natural antioxidants and film coatings. This will contribute to provide a theoretical reference for analyzing the formation mechanism of fish color deterioration, and thus propose targeted regulatory strategies for fish during cryopreservation.

The Antimicrobial and Antioxidant Effects of Bilayer Films Based on Polylactic Acid (PLA)/Chitosan: Starch Containing Bitter Orange Essential Oil on the Fresh Rainbow Trout (Onchorhynchus mykiss) Fillet

This study investigated the antibacterial properties of polylactic acid (PLA)/chitosan: starch films incorporated with bitter orange essential oil (BOEO) for preserving rainbow trout fillets. Three BOEO concentrations (0.7%, 1.4%, and 2.1% w/w) were incorporated via casting. Increased BOEO concentration enhanced film hydrophobicity and thermal resistance, but reduced tensile strength while increasing elongation. Atomic force microscopy revealed altered surface roughness. Antibacterial testing showed optimal activity against both Gram-positive and Gram-negative bacteria at 1.2% BOEO. Films containing 1.2% BOEO were applied to rainbow trout fillets, significantly reducing spoilage bacteria (total bacterial count, psychrotrophic, lactic acid bacteria, and Enterobacteriaceae), slowing chemical spoilage (pH and TBA values), and minimizing weight loss during 16 days of refrigerated storage (4°C). These results demonstrate the potential of BOEO-incorporated PLA/chitosan: starch films for extending the shelf life of rainbow trout.

Ameliorating Nickel-Induced Stress in Hypophthalmichthys molitrix (Silver Carp) Through Piper nigrum Extract Supplementation

The current study examined the damaging implications of nickel (Ni) toxicity on body composition, growth responses, histology and hematology of Hypophthalmichthys molitrix, as well as the potential mitigating effects of Piper nigrum extract. For this purpose, H. molitrix were distributed into six groups, namely T1, T2, T3, T4, T5, and T6. All treatments were assessed in triplicates. T1 was designated as the negative control treatment, receiving no Ni exposure or dietary supplementation, whereas T2 acted as the positive control treatment, exposed to sub-lethal concentrations of nickel chloride (NiCl2) at 3.6 mg/L. Groups T3-T6 received diets enriched with 1%, 2%, 3% and 4% P. nigrum extract, respectively and were also exposed to 3.6 mgL-1 NiCl2 toxicity. The findings of this investigation revealed that T2 exhibited decreased growth responses, characterized by a weight gain (WG) of 8.12 g, percentage weight gain (WG%) of 77.83% and specific growth rate (SGR) of 0.96. Additionally, T2 displayed altered hematological parameters such as reduced red blood cells (RBC: 1.3 × 106 mm-3) and hemoglobin levels (Hb: 5.8 g/100 ml), and increased white blood cell counts (WBC: 75.31 × 103 mm-3). Also, T2 showed reduced protein (13.14%), fat (2.15%), and moisture content (73.44%), hepatocyte degeneration, and Ni bioaccumulation in hepatic tissues. In contrast, T1 (control negative) and T3 (1% P. nigrum extract) demonstrated improved growth performance with WG of 18.49 g and 16.92 g, respectively. They also showed increased RBC (1.77 × 106 mm-3 and 2.77 × 106 mm-3) and Hb levels (9.65 g/100 ml and 8.15 g/100 ml), decreased WBC counts (6.12 × 103 mm-3 and 7.79 × 103 mm-3), and elevated protein (16.42% and 15.29%), fat (3.22% and 3.11%), and moisture content (76.92% and 76.6%), respectively. Furthermore, liver histological analysis revealed that dietary supplementation with 1% P. nigrum extract (T3) effectively minimized the adverse effects of NiCl2 toxicity, characterized by a normal central vein structure and significantly reduced histological damage. In conclusion, the results show that 1% P. nigrum extract supplementation significantly ameliorates the adverse effects on carcass composition, elevates growth responses, enhances hematological indices, and mitigates the toxic effects of Ni on the histology of H. molitrix. This comprehensive improvement in nutritional quality, growth rates, blood health, and tissue integrity suggests that P. nigrum extract has tremendous potential as a natural remedy for mitigating the adverse effects of Ni toxicity in aquatic species.

Nanotechnology in the manufacturing of sustainable food packaging: a review

At present, there is an escalating concern among consumers regarding the spoilage and safety of food items. Furthermore, the packaging materials used within the packaging industry are typically unsustainable food packaging. To confront this significant challenge, nanotechnology may offer a feasible alternative to standard packaging practices. Several naturally derived polymers are capable of substituting petrochemical-based polymers. The application of biopolymers has demonstrated an ability to prolong the shelf life of food items. However, these materials frequently exhibit limited functionality. The incorporation of nanomaterials can significantly enhance the capabilities of these films. Furthermore, the fields of nanotechnology and food packaging are trending areas of research that hold promise for addressing various challenges within the packaging sector. Integrating nanomaterials into food packaging materials yields significant advantages relative to traditional packaging approaches. It contributes to enhanced food quality and safety, provides consumers with insights into their dietary practices, enables the repair of packaging tears, and increases the longevity of food storage. Incorporating various nanomaterials into biobased films has gained prominence in sustainable food packaging. This review explores the general overview of the historical perspective of nanotechnology. In addition, we addressed the various kinds of nanomaterials involved in food packaging. The functions of nanomaterials in food packaging applications are briefly reviewed. The compilation and discussion highlight the nanotechnology for safe, sustainable, and satisfiable food packaging. Finally, the toxicity, safety, and future trends of the nanomaterials in sustainable food packaging were briefly summarized. This review underscores the necessity of nanotechnology in sustainable food packaging.

Effects of Chemically and Green Synthesized Zinc Oxide Nanoparticles on Shelf Life and Sensory Quality of Minced Fish (Pangasius hypophthalmus)

The purpose of this study was to investigate the effect of chemically and green synthesized zinc oxide nanoparticles (ZnO-NPs) on the shelf life and sensory quality of fish meat. In this study, ZnO-NPs were synthesized by employing the colloidal chemistry (CZnO-NPs) and green synthesis (GZnO-NPs) methods, and they were also characterized to assess their morphology. The synthesized ZnO-NPs, ZnO, and zinc acetate (ZnA) were used for the preservation and fortification of fish (Pangasius hypophthalmus) meat at 20 mg/kg of Zn. In a six-day storage study at 4 °C, the fish samples were evaluated for their sensory attributes (color and odor), physicochemical quality (pH and total volatile base nitrogen), oxidative changes (thiobarbituric acid-reactive substances and peroxide value), and microbial loads at 0, 3, and 6 days of storage. The fortification of raw fish with the synthesized CZnO-NPs produced better sensory attributes (color and odor) and maintained a pH non-conducive to microbial growth throughout the entire storage period compared with the control, ZnO, and ZnA-fortified samples. The GZnO-NPs largely did not provide any added advantage over CZnO-NPs but sometimes responded better than the control, ZnO, and ZnA samples. Oxidative status and total volatile base nitrogen were lower for CZnO-NPs in refrigerated fish compared with the other treatments. The ZnO-NP-fortified fish had the lowest counts of total viable bacteria, coliforms, Staphylococcus spp., and Vibrio spp. Hence, the fortification of fish with synthesized CZnO-NPs is promising as a food additive to reduce microbial spoilage and lipid peroxidation of fish in storage.

The preservation effect of biodegradable gelatin coating incorporated with grape seed oil on glazed shrimp

BACKGROUND

This study was conducted to investigate the quality and shelf life of shrimps (Parapenaeus longirostris, Lucas 1846) glazed with biodegradable gelatin solutions combined with grape (Vitis vinifera L.) seed oil (GSO). Therefore, shrimps were divided into five groups and were glazed with distilled water (control), G (gelatin), G + 5% GSO (gelatin with 5% GSO), G + 10% GSO (gelatin with 10% GSO) and G + 15% GSO (gelatin with 15% GSO). Glazed shrimps were vacuum packaged and stored at -18 °C for 12 months. Proximate composition of the shrimps was determined, and the microbial (total viable counts, psychrotrophic bacteria count and Enterobacteriaceae), sensorial, chemical (residual sulfite, pH, total volatile basic nitrogen, trimethylamine nitrogen, thiobarbituric acid reactive substances) analysis, colour measurement, and melanosis formation were evaluated throughout the storage period.

RESULTS

According to the analysis results, edible G + GSO coatings improved the meat quality and the brightness of the shrimps. The combined treatment reduced the quality loss of the shrimps which was caused by lipid content and prevented the total psychotropic bacteria growth throughout the storage. Moreover, glazing with G + GSO retarded the melanosis formation of the frozen shrimps.

CONCLUSION

The study results revealed that GSO may be a recommended alternatively to sodium metabisulfite, which is a hazardous chemical substance commonly used against melanosis of shrimps. © 2023 Society of Chemical Industry.

Development and characterization of edible films based on flaxseed gum incorporated with Piper betle extract

There has been a shift from use of petroleum-based plastics, causing serious environmental pollution, towards innovative and biodegradable edible packaging. The present study documents the development of composite edible films based on the flaxseed gum (FSG) modified by the incorporation of betel leaf extract (BLE). The films were assessed for physicochemical, mechanical, morphological, thermal, antimicrobial and structural characteristics. Scanning electron microscopy images indicated that the roughness decreased with an increase in BLE concentration. The water vapor permeability of the FSG-BLE films ranged from 4.68 to 1.59 × 10-9 g s- 1 m- 2 Pa- 1, lower than that of the control sample (6.77 × 10-9 g s- 1 m- 2 Pa- 1). The BLE4 (containing 10 % BLE) films had the highest tensile strength of 32.46 MPa compared to the control sample (21.23 MPa). Similarly, EAB and seal strength of the films incorporated with BLE were ameliorated. X-ray diffraction pattern and FTIR illustrated the shift of amorphous to crystalline behavior and a significant interaction among the BLE and FSG functional groups. Furthermore, the thermal stability of the treated films was not affected significantly however, they showed improved antimicrobial activity with the highest diameter of inhibition zone in the BLE4 sample. This study concluded that the FSG-BLE composite films (BLE4 in particular) can be considered as novel packaging material for food conservation coupled with a potential to enhance the shelf life of perishable food products.

Alginate/Pectin Film Containing Extracts Isolated from Cranberry Pomace and Grape Seeds for the Preservation of Herring

Alginate/pectin films supplemented with extracts from cranberry pomace (CE) or grape seeds (GE) were developed and applied to herring fillets that were stored for 18 days at 4 °C. Herring coated with films containing GE and CE inhibited the growth of Listeria monocytogenes and Pseudomonas aeruginosa during the storage period, whereas pure alginate/pectin films did not show an antimicrobial effect against the tested pathogens. The application of alginate/pectin films with CE and GE minimised pH changes and inhibited total volatile basic nitrogen (TVN) and the formation of thiobarbituric acid-reactive substances (TBARS) in the herring fillets. The coating of herring fillets with films with CE or GE resulted in three- and six-fold lower histamine formation and one-and-a-half- and two-fold lower cadaverine formation, respectively, when compared to unwrapped herring samples after 18 days of storage. The incorporation of 5% extracts isolated from cranberry pomace or grape seeds into the alginate/pectin film hindered herring spoilage due to the antimicrobial and antioxidant activity of the extracts.

An eco-friendly chitosan/cellulose acetate hybrid nanostructure containing Ziziphora clinopodioides essential oils for active food packaging applications

This work presents the fabrication and characterization of a hybrid nanostructure, Ziziphora clinopodioides essential oils (ZEO)-loaded chitosan nanoparticles (CSNPs-ZEO) embedded into cellulose acetate (CA) nanofibers (CA-CSNPs-ZEO). The CSNPs-ZEO were first synthesized through the ionic gelation method. Then, through simultaneous electrospraying and electrospinning processes, the nanoparticles were embedded in the CA nanofibers. The morphological and physicochemical characteristics of the prepared nanostructures were evaluated using different methods, including scanning electron microscopy (SEM), water vapor permeability (WVP), moisture content (MC), mechanical testing, differential scanning calorimetry (DSC), and release profile studies. The antibacterial activity of the nanostructures was explored on raw beef as a food model during 12 days of storage at 4 °C. The obtained results indicated the successful synthesis of CSNPs-ZEO nanoparticles with an average size of 267 ± 6 nm and their incorporation into the nanofibers matrix. Moreover, the CA-CSNPs-ZEO nanostructure showed a lower water vapor barrier and higher tensile strength compared with ZEO-loaded CA (CA-ZEO) nanofiber. The CA-CSNPs-ZEO nanostructure also exhibited strong antibacterial activity, which effectively extended the shelf-life of raw beef. The results demonstrated a strong potential for innovative hybrid nanostructures in active packaging to maintain the quality of perishable 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.

Utilization of Food Waste and By-Products in the Fabrication of Active and Intelligent Packaging for Seafood and Meat Products

Research on the utilization of food waste and by-products, such as peels, pomace, and seeds has increased in recent years. The high number of valuable compounds, such as starch, protein, and bioactive materials in waste and by-products from food manufacturing industries creates opportunities for the food packaging industry. These opportunities include the development of biodegradable plastics, functional compounds, active and intelligent packaging materials. However, the practicality, adaptability and relevance of up-scaling this lab-based research into an industrial scale are yet to be thoroughly examined. Therefore, in this review, recent research on the development of active and intelligent packaging materials, their applications on seafood and meat products, consumer acceptance, and recommendations to improve commercialization of these products were critically overviewed. This work addresses the challenges and potential in commercializing food waste and by-products for the food packaging industry. This information could be used as a guide for research on reducing food loss and waste while satisfying industrial demands.

Latest Trends in Sustainable Polymeric Food Packaging Films

Food packaging is the best way to protect food while it moves along the entire supply chain to the consumer. However, conventional food packaging poses some problems related to food wastage and excessive plastic production. Considering this, the aim of this work was to examine recent findings related to bio-based alternative food packaging films by means of conventional methodologies and additive manufacturing technologies, such as 3D printing (3D-P), with potential to replace conventional petroleum-based food packaging. Based on the findings, progress in the development of bio-based packaging films, biopolymer-based feedstocks for 3D-P, and innovative food packaging materials produced by this technology was identified. However, the lack of studies suggests that 3D-P has not been well-explored in this field. Nonetheless, it is probable that in the future this technology will be more widely employed in the food packaging field, which could lead to a reduction in plastic production as well as safer food consumption.

Silver Carp (Hypophthalmichthys molitrix) (Asian Silver Carp) Presence in Danube Delta and Romania-A Review with Data on Natural Reproduction

The Danube River has a large hydrographical basin, being the second largest river in Europe. The main channel flows through seven European countries with many species of fish inhabiting it. In this review we focused on the invasive species silver carp (Hypophthalmichthys molitrix), which plays an important ecological and economic role in its original habitat, but since introduced in Europe’s rivers, the species has posed a serious ecological risk under global warming. In this review paper, we gathered data regarding silver carp, such as when and how it entered the Danube Delta and the water temperature suitable for its growth and reproduction, mainly in the context of global warming, as well as the nature of nutrition and the ecological risk the species poses.

Impact of microencapsulated Ziziphora tenuior essential oil and orange fiber as natural-functional additives on chemical and microbial qualities of cooked beef sausage

The aim of the current study was to investigate the suitability of Ziziphora tenuior essential oil (ZEO) as a preservative. For this purpose, the effect of free and microencapsulated ZEO, combined with orange fiber, was determined on the chemical and microbial qualities of cooked beef sausage. In this study, modified starch was used for encapsulation of essential oil, and subsequently, 0.5% ZEO and 1% orange fiber were used for preparing cooked beef sausages during 60 days of storage at 4°C. To assess the microbial quality of samples, total viable count (TVC), psychrophilic count (PSY), and lactic acid bacteria (LAB) were analyzed. Furthermore, peroxide value (PV) and thiobarbituric acid reactive substances (TBARS) were tested to examine lipid oxidation. The most components of ZEO were pulegone (47.12%), isomenthone (14.57%), and 1,8-cineole (12.84%) according to GC-MS analysis. The reducing power, DPPH radical scavenging activity, MIC, and MBC of ZEO were 16.44 (EC50), 8.36 (IC50), 0.625-2.5, and 1.25-5 mg/ml, respectively. Moreover, sausage containing 0.5% microencapsulated ZEO in combination with 1% orange fiber showed the best results with the following values (p ≤ .05): TVC (3.69 log CFU/g), PSY (3.51 log CFU/g), LAB (3.1 log CFU/g), PV (10.41 meq/kg lipid), and TBARS (3.1 mg MDA/kg). This is due to the antimicrobial and antioxidant properties of microencapsulated essential oil. Therefore, the results of the present study can be applied in the meat industries as a new natural preservation method.

In vitro assessment of the acaricidal activity of a carvacrol shampoo on tick larvae

Ticks are a widely distributed arthropod of veterinary importance. Resistance of ticks to synthetic acaricides has become widespread, warranting the development of new drugs for tick management. Carvacrol is a volatile monoterpene, with promising results against various species of ticks; however, to be used for therapeutic purposes, carvacrol must be included in a formulation that makes its application feasible. This study aims to develop a formulation of a carvacrol-containing shampoo that is effective against two species of ticks: Rhipicephalus sanguineus and R. microplus. Shampoo sensory characteristics and pH were evaluated at 37, 25 and 5 °C, for a maximum of 15 days. The shampoo remained stable at 25 and 5 °C. The efficacy of the carvacrol-containing formulation against two species of ticks was assessed by the larval immersion test. Mortality of both tick species was significantly higher for the carvacrol shampoo than for a carvacrol hydroalcoholic solution. In conclusion, the carvacrol-containing shampoo showed larvicidal efficacy on ticks.

Impact of a Carboxymethyl Cellulose Coating Incorporated with an Ethanolic Propolis Extract on the Quality Criteria of Chicken Breast Meat

Recently, the demand for composite edible coatings has increased significantly as a new trend to confront the serious processing and storage problems that always arise regarding chicken meat. We aim to develop a carboxymethyl cellulose (CMC) coating containing various concentrations (0, 1, 2, 3, and 4%) of an ethanolic propolis extract (EPE) to maintain the quality and extend the shelf life of chicken breast meat stored at 2 °C for 16 days. The influence of the CMC and EPE coating on the physicochemical and microbiological quality parameters of chicken breast meat, e.g., pH, color, metmyoglobin (MetMb), lipid oxidation (thiobarbituric acid reactive substance, TBARS), and microbiological and sensory analyses, was studied. Significantly lower weight loss and pH (p ≤ 0.05) were noted in the coated samples compared with the uncoated samples (control) over the storage period. MetMb content was significantly reduced (p ≤ 0.05) in the coated samples compared to the control. Additionally, the addition of EPE to CMC was more effective in inhibiting microbial growth, preventing lipid oxidation, and keeping the overall acceptability of coated chicken breast meat compared to the control. This work presents CMC and EPE as alternative preservatives to produce active packaging coatings.

Effects of antioxidant types on the stabilization and in vitro digestion behaviors of silver carp scale gelatin-stabilized fish oil-loaded emulsions

Lipid oxidation is a major challenge in the development and storage of lipid-containing food products. In this work, we extracted aquatic gelatin from silver carp scales and studied the effects of antioxidant types (water-soluble and lipid-soluble types) on the stabilization, lipid oxidation, and in vitro digestion behaviors of silver carp scale gelatin-stabilized fish oil-loaded emulsions. Vitamin C (VC), a water-soluble antioxidant, and vitamin E (VE), a lipid-soluble antioxidant, had no obvious effects on the appearance, droplet size distribution, and droplet stability of the emulsion. VC slowed the liquid-gel transition of the emulsions at room temperature. The emulsion creaming stability decreased with the increase of VC concentration, whereas it increased with the increase of VE concentration. Lipid oxidation hierarchy of emulsion groups at room temperature were VC<VE<control<pure oil. Free fatty acids were mainly released from the silver carp scale gelatin-stabilized emulsions in the simulated intestinal fluid. Moreover, compared with the control group, VC increased the free fatty acid release percentages, whereas VE decreased them. This work provided useful information for developing antioxidants in the field of food science and in value-added utilization research of aquatic by-products.

Analysis of Alternative Shelf Life-Extending Protocols and Their Effect on the Preservation of Seafood Products

Seafood is essential to a healthy and varied diet due to its highly nutritious characteristics. However, seafood products are highly perishable, which results in financial losses and quality concerns for consumers and the industry. Due to changes in consumer concerns, demand for healthy products has increased. New trends focusing on reducing synthetic preservatives require innovation and the application of additional or alternative strategies to extend the shelf life of this type of product. Currently, refrigeration and freezing storage are the most common methods for fish preservation. However, refrigeration alone cannot provide long shelf-life periods for fish, and freezing worsens sensorial characteristics and consumer interest. Therefore, the need to preserve seafood for long periods without exposing it to freezing temperatures exists. This review focuses on the application of other approaches to seafood products, such as biodegradable films and coating technology; superchilling; irradiation; high-pressure processing; hyperbaric storage; and biopreservation with lactic acid bacteria, bacteriocins, or bacteriophages. The efficiency of these techniques is discussed based on their impact on microbiological quality, sensorial degradation, and overall preservation of the product’s nutritional properties. Although these techniques are already known, their use in the industrial processing of seafood is not widespread. Thus, the novelty of this review is the aggregation of recent studies on shelf life extension approaches, which provide useful information for the selection of the most appropriate technology and procedures and industrial innovation. Despite the fact that all techniques inhibit or delay bacterial proliferation and product decay, an undesirable sensory impact may occur depending on the treatment conditions. Although no technique appears to replace refrigeration, the implementation of additional treatments in the seafood processing operation could reduce the need for freezing, extending the shelf life of fresh unfrozen products.

Inhibition of Several Bacterial Species Isolated from Squid and Shrimp Skewers by Different Natural Edible Compounds

Seafood is an excellent source of nutrients, essential for a healthy diet, ranging from proteins and fatty acids to vitamins and minerals. Seafood products are highly perishable foods due to their nutritional characteristics and composition. The application of nontoxic, natural, and edible preservatives to extend the shelf-life and inhibit bacterial proliferation of several foods has been a hot topic. Consequently, this work aimed to perform the microbiological characterization of squid and shrimp skewers during their shelf-life (five days) and evaluate the susceptibility of randomly isolated microorganisms to several natural edible compounds so that their application for the preservation and shelf-life extension of the product might be analyzed in the future. The product had considerably high total microorganisms loads of about 5 log CFU/g at day zero and 9 log CFU/g at day five. In addition, high bacterial counts of Pseudomonas spp., Enterobacterales, and lactic acid bacteria (LAB) were found, especially on the last day of storage, being Pseudomonas the dominant genus. However, no Escherichia coli or Listeria monocytogenes were detected on the analyzed samples. One hundred bacterial isolates were randomly selected and identified through 16s rRNA sequencing, resulting in the detection of several Enterobacterales, Pseudomonas spp., and LAB. The antibacterial activity of carvacrol, olive leaf extract, limonene, Citrox®, different chitosans, and ethanolic propolis extracts was evaluated by the agar diffusion method, and the minimum inhibitory concentration was determined only for Citrox® since only this solution could inhibit all the identified isolates. At concentrations higher than or equal to 1.69% (v/v), Citrox® demonstrated bacteriostatic and bactericidal activity to 97% and 3% of the isolates, respectively. To our knowledge, there are no available data about the effectiveness of this commercial product on seafood isolates. Although preliminary, this study showed evidence that Citrox® has the potential to be used as a natural preservative in these seafood products, improving food safety and quality while reducing waste. However, further studies are required, such as developing a Citrox®-based coating and its application on this matrix to validate its antimicrobial effect.

Metallic Nanoparticles in the Food Sector: A Mini-Review

Nanomaterials, and in particular metallic nanoparticles (MNPs), have significantly contributed to the production of healthier, safer, and higher-quality foods and food packaging with special properties, such as greater mechanical strength, improved gas barrier capacity, increased water repellency and ability to inhibit microbial contamination, ensuring higher quality and longer product shelf life. MNPs can also be incorporated into chemical and biological sensors, enabling the design of fast and sensitive monitoring devices to assess food quality, from freshness to detection of allergens, food-borne pathogens or toxins. This review summarizes recent developments in the use of MNPs in the field of food science and technology. Additionally, a brief overview of MNP synthesis and characterization techniques is provided, as well as of the toxicity, biosafety and regulatory issues of MNPs in the agricultural, feed and food sectors.

Effects of Chitosan and Duck Fat-Based Emulsion Coatings on the Quality Characteristics of Chicken Meat during Storage

Chicken meat is a popular food commodity that is widely consumed worldwide. However, the shelf-life or quality maintenance of chicken meat is a major concern for industries because of spoilage by microbial growth. The aim of this study was to evaluate the effects of chitosan and duck fat-based emulsion coatings on the quality characteristics and microbial stability of chicken meat during refrigerated storage. The coated chicken meat samples were as follows: control (non-coated), DFC0 (coated with duck fat), DFC0.5 (coated with duck fat and 0.5% chitosan), DFC1 (coated with duck fat and 1% chitosan), DFC2 (coated with duck fat and 2% chitosan), and SOC2 (coated with soybean oil and 2% chitosan). The results showed that the apparent viscosity and coating rate were higher in DFC2 than in other groups. Physicochemical parameters (pH, color, and Warner-Bratzler shear force) were better in DFC2 than those in other groups during 15 days of storage. Moreover, DFC2 delayed lipid oxidation, protein deterioration, and growth of microorganisms during storage. These data suggest that chitosan-supplemented duck fat-based emulsion coating could be used to maintain the quality of raw chicken meat during refrigerated storage.

Silver carp scale gelatins for the stabilization of fish oil-loaded emulsions

Herein, three types of silver carp scale gelatins were extracted, and their molecular weight distribution, structural properties, functional properties and emulsifying properties were investigated and discussed. Acetic acid-extracted gelatin (AAG), hot water-extracted gelatin (HWG), and pepsin enzyme-extracted gelatin (PEG) showed similar and four clear bands in sodium dodecyl sulfate-polyacrylamide gel electrophoresis pattern, whereas they showed different β chain amounts and β-sheet percentages. The water-holding capacity values (g/g of gelatin) were: AAG (16.8 ± 1.1) > HWG (14.0 ± 0.7) ≈ PEG (13.5 ± 1.6). The fat-binding capacity values (g/g of gelatin) were: AAG (11.8 ± 0.3) > HWG (9.5 ± 1.3) > PEG (5.3 ± 0.4). Emulsion droplet sizes and creaming index values decreased with the increase of gelatin concentrations for all the fish oil-loaded emulsions stabilized by three types of gelatins. Compared with PEG, AAG and HWG show similar and higher emulsion stability at high gelatin concentration (10 mg/mL). The stabilization mechanism of fish oil-loaded silver carp scale gelatin-stabilized emulsions involved an "extraction method-protein molecular weight distribution-protein molecular structure-molecular interaction-emulsibility-droplet structure-emulsion stability" route. This work would be beneficial for the research on the relationship of structure and function of gelatin and to the comprehensive utilization of aquatic products.

Biodegradable Active Packaging as an Alternative to Conventional Packaging: A Case Study with Chicken Fillets

Innovative active packaging has the potential to maintain the food quality and preserve the food safety for extended period. The aim of this study was to discover the effect of active films based on commercially available polylactic acid blend (PLA_b) and natural active components on the shelf life and organoleptic properties of chicken fillets and to find out; to what extent they can be used as replacement to the traditional packaging materials. In this study, commercially available PLA_b was compounded with citral and cinnamon oil. Active films with 300 µm thickness were then produced on a blown film extruder. The PLA_b-based films were thermoformed into trays. Fresh chicken breast fillets were packed under two different gas compositions, modified atmosphere packaging of 60% CO₂/40% N₂, and 75% O₂/25% CO₂ and stored at 4 °C. The effect of active packaging materials and gas compositions on the drip loss, dry matter content, organoleptic properties, and microbial quality of the chicken fillets were studied over a storage time of 24 days. The presence of active components in the compounded films was confirmed with FTIR, in addition the release of active components in the headspace of the packaging was established with GC/MS. Additionally, gas barrier properties of the packages were studied. No negative impact on the drip loss and dry matter content was observed. The results show that PLA_b-based active packaging can maintain the quality of the chicken fillets and have the potential to replace the traditional packaging materials, such as APET/PE trays.

Antimicrobial Polyamide-Alginate Casing Incorporated with Nisin and ε-Polylysine Nanoparticles Combined with Plant Extract for Inactivation of Selected Bacteria in Nitrite-Free Frankfurter-Type Sausage

The effects of combining a polyamide-alginate casing incorporated with nisin (100 ppm and 200 ppm) and ε-polylysine (500 ppm and 1000 ppm) nanoparticles and a mixed plant extract as ingredient in sausage formulation (500 ppm; composed of olive leaves (OLE), green tea (GTE) and stinging nettle extracts (SNE) in equal rates) were studied to improve the shelf life and safety of frankfurter-type sausage. The film characteristics and microbiological properties of sausage samples were evaluated. Sausage samples were packaged in polyethylene bags (vacuum condition) and analysed during 45 days of storage at 4 °C. Control sausages were also treated with 120 ppm sodium nitrite. Polyamide-alginate films containing 100 ppm nisin and 500 ε-PL nanoparticles had the highest ultimate tensile strength compared to other films. However, 100 ppm nisin and 500 ε-PL nanoparticles decreased water vapour permeability of films. The results also revealed that nisin nanoparticles had significantly (p < 0.05) low inhibitory effects against Escherichia coli, Staphylococcus aureus, molds and yeasts and total viable counts compared to control and ε-PL nanoparticles. Furthermore, 1000 ppm ε-PL nanoparticles displayed the highest antimicrobial activity. Based on the obtained results, the films containing ε-PL nanoparticle could be considered as a promising packaging for frankfurter-type sausages.

Essential Oil-Containing Polysaccharide-Based Edible Films and Coatings for Food Security Applications

The wastage of food products is a major challenge for the food industry. In this regard, the use of edible films and coatings have gained much attention due to their ability to prevent the spoilage of the food products during handling, transport, and storage. This has effectively helped in extending the shelf-life of the food products. Among the various polymers, polysaccharides have been explored to develop edible films and coatings in the last decade. Such polymeric systems have shown great promise in microbial food safety applications. The inclusion of essential oils (EOs) within the polysaccharide matrices has further improved the functional properties of the edible films and coatings. The current review will discuss the different types of polysaccharides, EOs, methods of preparing edible films and coatings, and the characterization methods for the EO-loaded polysaccharide films. The mechanism of the antimicrobial activity of the EOs has also been discussed in brief.

Nanocomposites for Food Packaging Applications: An Overview

There is a strong drive in industry for packaging solutions that contribute to sustainable development by targeting a circular economy, which pivots around the recyclability of the packaging materials. The aim is to reduce traditional plastic consumption and achieve high recycling efficiency while maintaining the desired barrier and mechanical properties. In this domain, packaging materials in the form of polymer nanocomposites (PNCs) can offer the desired functionalities and can be a potential replacement for complex multilayered polymer structures. There has been an increasing interest in nanocomposites for food packaging applications, with a five-fold rise in the number of published articles during the period 2010–2019. The barrier, mechanical, and thermal properties of the polymers can be significantly improved by incorporating low concentrations of nanofillers. Furthermore, antimicrobial and antioxidant properties can be introduced, which are very relevant for food packaging applications. In this review, we will present an overview of the nanocomposite materials for food packaging applications. We will briefly discuss different nanofillers, methods to incorporate them in the polymer matrix, and surface treatments, with a special focus on the barrier, antimicrobial, and antioxidant properties. On the practical side migration issues, consumer acceptability, recyclability, and toxicity aspects will also be discussed.

Potential of Propolis Extract as a Natural Antioxidant and Antimicrobial in Gelatin Films Applied to Rainbow Trout (Oncorhynchus mykiss) Fillets

Usage of edible films and coatings alone or incorporated with natural extracts are a new approach to preservation and packaging of food. In this study, therefore, the microbiological, chemical quality, and sensorial changes of rainbow trout fillets coated with gelatin films supplemented with propolis extract (PE) (2, 8, 16%), as a source of polyphenols, were determined during 15 days of refrigerated storage (4 ± 1 °C). According to peroxide value (PV) and thiobarbituric acid reactive substances (TBARS) assays, lipid oxidation was delayed in the fillets coated with gelatin films incorporated with PE comparing with the control and gelatin-coated (without PE) fillets. The total volatile basic nitrogen (TVB-N) value of rainbow trout fillets showed an increase in all groups at the end of storage, observing the lowest values in the fillets coated with gelatin films prepared with 16% PE. Gelatin films enriched with PE had great inhibitory effects on the microbial growth in rainbow trout fillets. The addition of PE enhanced the effectiveness of gelatin films and delayed the lipid oxidation and sensory and microbial deterioration in trout fillets coated with these films. Thus, PE can be recommended to be used as a natural antioxidant and antimicrobial additive with gelatin films to maintain rainbow trout fillet quality.

Biodegradable Antimicrobial Food Packaging: Trends and Perspectives

This review presents a perspective on the research trends and solutions from recent years in the domain of antimicrobial packaging materials. The antibacterial, antifungal, and antioxidant activities can be induced by the main polymer used for packaging or by addition of various components from natural agents (bacteriocins, essential oils, natural extracts, etc.) to synthetic agents, both organic and inorganic (Ag, ZnO, TiO2 nanoparticles, synthetic antibiotics etc.). The general trend for the packaging evolution is from the inert and polluting plastic waste to the antimicrobial active, biodegradable or edible, biopolymer film packaging. Like in many domains this transition is an evolution rather than a revolution, and changes are coming in small steps. Changing the public perception and industry focus on the antimicrobial packaging solutions will enhance the shelf life and provide healthier food, thus diminishing the waste of agricultural resources, but will also reduce the plastic pollution generated by humankind as most new polymers used for packaging are from renewable sources and are biodegradable. Polysaccharides (like chitosan, cellulose and derivatives, starch etc.), lipids and proteins (from vegetal or animal origin), and some other specific biopolymers (like polylactic acid or polyvinyl alcohol) have been used as single component or in blends to obtain antimicrobial packaging materials. Where the package's antimicrobial and antioxidant activities need a larger spectrum or a boost, certain active substances are embedded, encapsulated, coated, grafted into or onto the polymeric film. This review tries to cover the latest updates on the antimicrobial packaging, edible or not, using as support traditional and new polymers, with emphasis on natural compounds.

Effect of gamma irradiation on physico-mechanical and structural properties of active Farsi gum-CMC films containing Ziziphora clinopodioides essential oil and lignocellulose nanofibers for meat packaging

The objective of this study was to examine the effect of gamma irradiation (0, 2.5, and 5 kGy) on physico-mechanical and structural characteristics of films based on Farsi gum-carboxymethyl cellulose supplemented with Ziziphora clinopodioides essential oil (ZEO; 0%, 1%, and 2%) and lignocellulose nanofibers (LCNF; 0%, 1%, and 2%), and their application on fresh minced beef meat's shelf-life during refrigerated temperature (4 ± 1 °C) for 16 days. Gamma irradiation under the ⁶⁰ Co source at 2.5 and 5 kGy doses did not have a significant effect on thickness, tensile strength, swelling index, oxygen permeability, and water vapor transmission rate of prepared films (P > 0.05). The best microbiological (total viable count, psychrotrophic bacterial count, Pseudomonas spp., Brochothrix thermosphacta, lactic acid bacteria, and Enterobacteriaceae) and chemical (thiobarbituric acid reactive substances, total volatile base nitrogen content, and peroxide value) properties were recorded for samples packaged with ZEO 2% + LCNF 2%, followed by ZEO 2% + LCNF 1%, ZEO 1% + LCNF 2%, and ZEO 1% + LCNF 1%. These results indicate acceptable extensions of hurdle technology for prolonged refrigeration of minced beef meat. PRACTICAL APPLICATION: The application of active packaging films has received considerable interest in extending the shelf-life of perishable foods during prolonged chilled storage. The effects of active Farsi gum-carboxymethyl cellulose films supplemented with Ziziphora clinopodioides essential oil 2% + lignocellulose nanofibers 2% resulted in delaying lipid oxidation and microbial spoilage growth of refrigerated minced beef meat and consequently extending the shelf-life during storage for at least 16 days.

Application of Edible Alginate Films with Pineapple Peel Active Compounds on Beef Meat Preservation

Alginate-based edible films containing natural antioxidants from pineapple peel were applied in the microbial spoilage control, color preservation, and barrier to lipid oxidation of beef steaks under storage at 4 °C for five days. Different stabilization methods of pineapple peel compounds were used before incorporation into alginate films, including extracted compounds with an hydroalcoholic solvent encapsulated in microparticles, microparticles produced by spray-drying pineapple peel juice, and particles obtained by milling freeze dried pineapple peel. Bioactive films exhibited higher antioxidant activity (between 0.15 µmol to 0.35 µmol FeSO4.7H2O/g dried film) than the alginate film without these compounds (0.02 µmol FeSO4.7H2O/g dried film). Results showed that control films without active compounds had no significant effect on decreasing the microbial load of aerobic mesophilic and Pseudomonas spp., while the films containing encapsulated hydroalcoholic extract showed a significant inhibitory effect on microbial growth of meat at two days of storage. Alginate films containing peel encapsulated extract were effective for maintaining the color hue and intensity of red beef meat samples. Pineapple peel antioxidants have the potential to retard lipid oxidation in meat samples, and the possibility of incorporation of a higher amount of pineapple peel bioactive compounds in the films should be investigated.