Evaluation of bionanocomposites as packaging material on properties of soft white cheese during storage period

Development and characterization of eco-friendly guar gum-agar-beeswax-based active packaging film for cheese preservation

In this work, an attempt has been made to develop a novel natural polysaccharide-based composite packaging biofilm prepared through a solution casting method. The biofilm is prepared from guar gum (GG) and agar-agar (AA) beeswax (BE). The incorporation of 20 % wt./wt.glycerol BE in the blended polymer GG/AA (50:50) (GG/AA/BE20 (50:50)) film shows a reduction in water solubility (66.67 %), water vapour permeability (69.28 %) and oxygen permeability (72.23 %). Moreover, GG/AA/BE20 (50:50) shows an increment in the tensile strength and elongation of a break by 48.32 % and 26.05 %, respectively, compared to pristine GG film. The scanning electron microscopy (SEM) image reveals defects-free smooth surfaces of the film. The Fourier transform-infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) demonstrated the strong hydrogen bonding between GG, AA, and BE. The biodegradable film shows 99 % degradation within 28 days when placed in the soil. The developed film plays a crucial role in extending the shelf life of cheese, effectively maintaining its moisture content, texture, colour, and pH over a span of up to two months from the point of packaging. These results suggest that GG/AA/BE20 (50:50) composite film is a promising packaging film for cheese preservation.

Nanotechnology in food packaging materials: role and application of nanoparticles

Global concerns about food security, driven by rising demand, have prompted the exploration of nanotechnology as a solution to enhance food supply. This shift comes in response to the limitations of conventional technologies in meeting the ever-increasing demand for food products. Consequently, nanoparticles play a crucial role in enhancing food production, preservation, and extending shelf life by imparting exceptional properties to materials. Nanoparticles and nanostructures with attributes like expansive surface area and antimicrobial efficacy, are versatile in both traditional packaging and integration into biopolymer matrices. These distinctive qualities contribute to their extensive use in various food sector applications. Hence, this review explores the physicochemical properties, functions, and biological aspects of nanoparticles in the context of food packaging. Furthermore, the synergistic effect of nanoparticles with different biopolymers, alongside its different potential applications such as food shelf-life extenders, antimicrobial agents and as nanomaterials for developing smart packaging systems were summarily explored. While the ongoing exploration of this research area is evident, our review highlights the substantial potential of nanomaterials to emerge as a viable choice for food packaging if the challenges regarding toxicity are carefully and effectively modulated.

Advances in sustainable food packaging applications of chitosan/polyvinyl alcohol blend films

Researchers are addressing environmental concerns related to petroleum-based plastic packaging by exploring biopolymers from natural sources, chemical synthesis, and microbial fermentation. Despite the potential of individual biopolymers, they often exhibit limitations like low water resistance and poor mechanical properties. Blending polymers emerges as a promising strategy to overcome these challenges, creating films with enhanced performance. This review focuses on recent advancements in chitosan/polyvinyl alcohol (PVA) blend food packaging films. It covers molecular structure, properties, strategies for performance improvement, and applications in food preservation. The blend's excellent compatibility and intermolecular interactions make it a promising candidate for biodegradable films. Future research should explore large-scale thermoplastic technologies and investigate the incorporation of additives like natural extracts and nanoparticles to enhance film properties. Chitosan/PVA blend films offer a sustainable alternative to petroleum-based plastic packaging, with potential applications in practical food preservation.

Optical, thermal, mechanical, and antibacterial properties of polyvinyl alcohol/sodium alginate/ZnMn2O4 nanocomposites films for various optical devices and food packaging applications

This work involves preparing zinc manganite nanoparticles (ZnMn2O4 NPs) using the Sol-gel method. Polymer nanocomposites of polyvinyl alcohol (PVA)/Sodium alginate (NaAlg)- ZnMn2O4 NPs were created using the solution casting technique. The polymer nanocomposites films were made with varying weight percentages of ZnMn2O4 nanoparticles. With the addition of nanofiller, the reduced direct and indirect energy band gap values and increased Urbach energy values were discovered in the UV-Vis data. XRD data showed a reduction in crystallinity degree with dopant. ZnMn2O4 NPs had a strong interaction with PVA/NaAlg blend, as confirmed by FTIR. The addition of ZnMn2O4 NPs led to improved thermal stability of the polymer nanocomposites films. Additionally, the nanocomposites films' mechanical characteristics were examined. The loading of ZnMn2O4 nanoparticles has been associated with an increasing trend in the mechanical properties of the nanocomposites, including its toughness, Young's modulus, Tensile strength (Ts), and elongation. The antibacterial activity of the nanocomposites against fungus and bacteria was studied. Additionally, PVA/NaAlg-ZnMn2O4 nanocomposites films had good antibacterial characteristics against environmental microorganisms such as Gram-positive (G+) S. aureus and Gram-negative(G-) E. coli bacteria as well as fungi C. albicans and A. niger. It was observed that the biodegradability of the nanocomposite films was lower compared to the pure PVA/NaAlg film. Compared to pure film, the water solubility was decreased upon the addition of ZnMn2O4 NPs. After ZnMn2O4 was added to the pure blend, the WVTR decreased. The produced polymer nanocomposites films appear to be a promising material for food packing, according to these results.

Novel chitosan-based smart bio-nanocomposite films incorporating TiO2 nanoparticles for white bread preservation

Chitosan (CS)-based bio-nanocomposite food packaging films were prepared via solvent-casting method by incorporating a unique combination of additives and fillers, including polyvinyl alcohol (PVA), glycerol, Tween 80, castor oil (CO), and nano titanium dioxide (TiO2) in various proportions to enhance film properties. For a comprehensive analysis of the synthesized films, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), tensile testing, field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDS), and UV-vis spectrophotometry were employed. Furthermore, the antimicrobial efficacy of the films against S. aureus, E. coli, and A. niger was examined to assess their potential to preserve food from foodborne pathogens. The results claimed that the inclusion of castor oil and TiO2 nanoparticles considerably improved antimicrobial properties, UV-vis light barrier properties, thermal stability, optical transparency, and mechanical strength of the films, while reducing their water solubility, moisture content, water vapor and oxygen permeability. Based on the overall analysis, CS/PVA/CO/TiO2-0.3 film can be selected as the optimal one for practical applications. Furthermore, the practical application of the optimum film was evaluated using white bread as a model food product. The modified film successfully extended the shelf life of bread to 10 days, surpassing the performance of commercial LDPE packaging (6 days), and showed promising attributes for applications in the food packaging sector. These films exhibit superior antimicrobial properties, improved mechanical strength, and extended shelf life for food products, marking a sustainable and efficient alternative to conventional plastic packaging in both scientific research and industrial applications.

Application of a Chitosan-based Active Packaging Film Prepared with Cell-free Supernatant of Lacticaseibacillus paracasei ALAC-4 in Mongolian Cheese Preservation

Fungal spoilage of food is a worldwide concern prompting the development of many antimicrobial agents and applications. In this study, the cell-free supernatant (CFS) of Lacticaseibacillus paracasei ALAC-4 had a significant inhibition effect on fungi. The CFS with antifungal activities were combined with chitosan (CS) matrix to prepare an active packaging CS-CFS films by using a solvent casting method and used for the packaging of Mongolian cheese for 15 days during storage at 4 ± 1℃. The optimized formulation of the film were 1.25% (w/v) chitosan, 1.75% (w/v) gelatin, 0.3% (v/v) glycerol, and 9.6% (w/v) CFS. It was found that CS-CFS films exhibited strong antifungal activities against molds and yeasts, especially Candida albicans, and also had excellent mechanical properties. Additionally, FTIR spectroscopy indicated that hydrogen bonds between the CFS and CS formed, and there was a smooth surface, compact cross-section observed in SEM morphologies of CS-CFS films. Furthermore, CS-CFS film also displayed a strong antifungal effect against molds and yeasts on cheese surface. These results suggest that the chitosan-based CS-CFS film has a promising application for Mongolian cheese and food preservation.

Innovations in Food Packaging for a Sustainable and Circular Economy

Packaging is fundamental to maintaining the quality of food, but its contribution with a negative footprint to the environment must be completely changed worldwide to reduce pollution and climate change. Innovative and sustainable packaging and new strategies of reutilization are necessary to reduce plastic waste accumulation, maintain food quality and safety, and reduce food losses and waste. The purpose of this chapter is to present innovations in food packaging for a sustainable and circular economy. First, to present the eco-design packaging approach as well as new strategies for recycled or recyclable materials in food packaging. Second, to show current trends in new packaging materials developed from the use of agro-industrial wastes as well as new methods of production, including 3D/4D printing, electrostatic spinning, and the use of nanomaterials.

A review of environmental friendly green composites: production methods, current progresses, and challenges

The growing concern about environmental damage and the inability to meet the demand for more versatile, environmentally friendly materials has sparked increasing interest in polymer composites derived from renewable and biodegradable plant-based materials, mainly from forests. These composites are mostly referred to as "green" and they can be widely employed in many industrial applications. Green composites are less harmful to the environment and could be potential substitutes for petroleum-based polymeric materials. It is helpful to limit usage of fossil oil assets by developing biopolymer matrices such as cellulose-reinforced biocomposites using renewable assets such as plant oils, carbohydrates, and proteins. This paper focuses on green composites processing utilizing a variety of naturally available resources, sustainable materials which are not detrimental to the environment, new scientific signs of progress in achieving green sustainable development, as well as nanotechnology and its environmental consequences. Additionally, the environmental impacts of different composite materials are examined in this paper, along with their production from eco-friendly materials. Moreover, the manufacturing aspects of green composites and some concerns related to their production are also discussed. The merits of green composite materials and valid reasons why they are a valuable substitute for the traditionally used composite materials are also covered.

Novel Bionanocomposites Based on Cinnamon Nanoemulsion and TiO2-NPs for Preserving Fresh Chicken Breast Fillets

In this study, bionanocomposite coating solutions were created using polyvinyl alcohol (PVA) and chitosan (Cs), with different concentrations of cinnamon essential oil in nanoemulsion (n-CEO; 0%, 5%, 10%, and 20%) and TiO2 nanoparticles (TiO2-NPs). The bionanocomposite was characterized using Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy with EDX, and mechanical and barrier property assessment. Additionally, antimicrobial and antioxidant properties and total phenols were evaluated. Generally, mechanical and barrier properties were enhanced with increasing n-CEO concentrations with a favorable distribution in film matrix. Moreover, total phenols, antioxidant, and antimicrobial activities were also enhanced a broader inhibition pattern against A. flavus, gram-positive, and gram-negative bacteria. The influence of n-CEO and TiO2-NPs blended into bionanocomposite on preservation of fresh chicken breast fillets during 21 days of refrigeration was evaluated. Added n-CEO concentration, especially 20%, and TiO2-NPs enhanced antimicrobial properties and extended preservation time up to 14 days compared to uncoated samples. Furthermore, weight loss was decreased during storage of coated samples. Thus, PVA/Cs/TiO2–NPs with n-CEO bionanocomposites may be useful as a coating for chicken breast fillets to control microbial growth and reduce weight loss during cold storage.

Chronic effects of two rutile TiO2 nanomaterials in human intestinal and hepatic cell lines

Background

TiO₂ nanomaterials (NMs) are present in a variety of food and personal hygiene products, and consumers are exposed daily to these NMs through oral exposition. While the bulk of ingested TiO₂ NMs are eliminated rapidly in stool, a fraction is able to cross the intestinal epithelial barrier and enter systemic circulation from where NMs can be distributed to tissues, primarily liver and spleen. Daily exposure to TiO₂ NMs, in combination with a slow rate of elimination from tissues, results in their accumulation within different tissues. Considerable evidence suggests that following oral exposure to TiO₂ NMs, the presence of NMs in tissues is associated with a number of adverse effects, both in intestine and liver. Although numerous studies have been performed in vitro investigating the acute effects of TiO₂ NMs in intestinal and hepatic cell models, considerably less is known about the effect of repeated exposure on these models. In this study, we investigated the cytotoxic effects of repeated exposure of relevant models of intestine and liver to two TiO₂ NMs differing in hydrophobicity for 24 h, 1 week and 2 weeks at concentrations ranging from 0.3 to 80 µg/cm². To study the persistence of these two NMs in cells, we included a 1-week recovery period following 24 h and 1-week treatments. Cellular uptake by TEM and ToF–SIMS analyses, as well as the viability and pro-inflammatory response were evaluated. Changes in the membrane composition in Caco-2 and HepaRG cells treated with TiO₂ NMs for up to 2 weeks were also studied.

Results

Despite the uptake of NM-103 and NM-104 in cells, no significant cytotoxic effects were observed in either Caco-2 or HepaRG cells treated for up to 2 weeks at NM concentrations up to 80 µg/cm²_. In addition, no significant effects on IL-8 secretion were observed. However, significant changes in membrane composition were observed in both cell lines. Interestingly, while most of these phospholipid modifications were reversed following a 1-week recovery, others were not affected by the recovery period.

Conclusion

These findings indicate that although no clear effects on cytotoxicity were observed following repeated exposure of differentiated Caco-2 and HepaRG cells to TiO₂ NMs, subtle effects on membrane composition could induce potential adverse effects in the long-term.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12989-022-00470-1.

Recent development in antibacterial activity and application of nanozymes in food preservation

Nanozymes with excellent broad-spectrum antibacterial properties offers an alternative strategy for food preservation. This review comprehensively summarized the antibacterial mechanisms of nanozymes, including the generation of reactive oxygen species (ROS) and the destruction of biofilms. Besides, the primary factors (size, morphology, hybridization, light, etc.) regulating the antibacterial activity of different types of nanozymes were highlighted in detail, which provided effective guidance on how to design highly efficient antibacterial nanozymes. Moreover, this review presented elaborated viewpoints on the unique applications of nanozymes in food preservation, including the selection of nanozymes loading matrix, fabrication techniques of nanozymes-based antibacterial films/coatings, and the recent advances in the application of nanozymes-based antibacterial films/coatings in food preservation. In the end, the safety issues of nanozymes have also been mentioned. Overall, this review provided new avenues in the field of food preservation and displayed great prospects.

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.

Extraction of cellulose nanocrystals from areca waste and its application in eco-friendly biocomposite film

Areca nut husk fibers are easily available and they are abundant agricultural waste, whose utilization to high value products needs more attention. The present study aims at the extraction of cellulose nanocrystals (CNCs) from areca nut husk fibers and the evaluation of its reinforcement capacity in polyvinyl alcohol (PVA) and chitosan (CS) film. The CNC showed rod-like structures, which were confirmed by TEM and AFM analysis. The diameter of the isolated CNC was 19 ± 3.3 nm; the length was about 195 ± 24 nm with an aspect ratio of 10.2 ± 6.8. The zeta potential of CNC was -15.3 ± 1.2 mV. Fourier Transform Infrared Spectroscopy analysis showed that the non-cellulosic compounds were effectively eliminated, and the X-ray diffraction results showed that CNC had higher crystallinity than the raw, alkali, and the bleached fibers. Thermogravimetric analysis revealed good thermal stability for the CNC. Moreover, the effects of the incorporation of CNC on the optical and tensile behaviours of the bionanocomposite film were investigated. The bionanocomposite film retained the same transparency as the PVA/CS film, indicating that the CNC was disseminated evenly in the film. The incorporation of CNC (3 wt%) to the PVA/CS film enhanced the tensile strength of the bionanocomposite film (9.46 ± 1.6 MPa) when compared to the control films (7.81 ± 1.4 MPa). Furthermore, the prepared nanobiocomposite film exhibited good antimicrobial activity against foodborne pathogenic bacteria and postharvest pathogenic fungi. These findings suggest that the bionanocomposite film might be suitable for food packaging applications.

Novel Bio-Based Materials and Applications in Antimicrobial Food Packaging: Recent Advances and Future Trends

Food microbial contamination not only poses the problems of food insecurity and economic loss, but also contributes to food waste, which is another global environmental problem. Therefore, effective packaging is a compelling obstacle for shielding food items from outside contaminants and maintaining its quality. Traditionally, food is packaged with plastic that is rarely recyclable, negatively impacting the environment. Bio-based materials have attracted widespread attention for food packaging applications since they are biodegradable, renewable, and have a low carbon footprint. They provide a great opportunity to reduce the extensive use of fossil fuels and develop food packaging materials with good properties, addressing environmental problems and contributing significantly to sustainable development. Presently, the developments in food chemistry, technology, and biotechnology have allowed us to fine-tune new methodologies useful for addressing major safety and environmental concerns regarding packaging materials. This review presents a comprehensive overview of the development and potential for application of new bio-based materials from different sources in antimicrobial food packaging, including carbohydrate (polysaccharide)-based materials, protein-based materials, lipid-based materials, antibacterial agents, and bio-based composites, which can solve the issues of both environmental impact and prevent foodborne pathogens and spoilage microorganisms. In addition, future trends are discussed, as well as the antimicrobial compounds incorporated in packaging materials such as nanoparticles (NPs), nanofillers (NFs), and bio-nanocomposites.

Metal-based nanoparticles, sensors, and their multifaceted application in food packaging

Due to the global rise of the human population, one of the top-most challenges for poor and developing nations is to use the food produces safely and sustainably. In this regard, the storage of surplus food (and derived products) without loss of freshness, nutrient stability, shelf life, and their parallel efficient utilization will surely boost the food production sector. One of the best technologies that have emerged within the last twenty years with applications in the packaging of food and industrial materials is the use of green mode-based synthesized nanoparticles (NPs). These NPs are stable, advantageous as well as eco-friendly. Over the several years, numerous publications have confirmed that these NPs exert antibacterial, antioxidant, and antifungal activity against a plethora of pathogens. The storage in metal-based NPs (M-NPs) does not hamper the food properties and packaging efficiency. Additionally, these M-NPs help in the improvement of properties including freshness indicators, mechanical properties, antibacterial and water vapor permeability during food packaging. As a result, the nano-technological application facilitates a simple, alternate, interactive as well as reliable technology. It even provides positive feedback to food industries and packaging markets. Taken together, the current review paper is an attempt to highlight the M-NPs for prominent applications of antimicrobial properties, nanosensors, and food packaging of food items. Additionally, some comparative reports associated with M-NPs mechanism of action, risks, toxicity, and overall future perspectives have also been made.

Chemical and organoleptic changes of curd cheese stored in new and reused active packaging systems made of Ag-graphene-TiO2-PLA

The study reports obtaining, characterization and evaluation of the preservation efficacy of nano-Ag-graphene-TiO₂-polylactic acid (PLA) film during the storage of the curd cheese. The reusability of the active package was also evaluated. The mechanical resistance of the film was improved by 30% following the composite addition. Water vapour permeability decreased by 11-27% when the composite was incorporated into PLA in a mass percentage ranged between 0.5 and 3%. The highest fat permeability was obtained for PLA3% at 4 °C. The oxygen permeability of PLA3% is 24.6% lower than that of neat-PLA. PLA0.5% and PLA3% presented the highest antibacterial activity. PLA3% achieved the lowest solubility in food simulants at 4 °C compared to PLA and reference. The best active packages for curd storage were PLA0.5% and PLA3%. They showed also the lowest depreciation from the first to the second use. Their active role is kept 100% and 85% respectively, during the second use.

Employing Nanosilver, Nanocopper, and Nanoclays in Food Packaging Production: A Systematic Review

Over the past decade, there has been an increasing demand for “ready-to-cook” and “ready-to-eat” foods, encouraging food producers, food suppliers, and food scientists to package foods with minimal processing and loss of nutrients during food processing. Following the increasing trend in the customer’s demands for minimally processed foodstuffs, this underscores the importance of promising interests toward industrial applications of novel and practical approaches in food. Along with substantial progress in the emergence of “nanoscience”, which has turned into the call of the century, the efficacy of conventional packaging has faded away. Accordingly, there is a wide range of new types of packaging, including electronic packaging machines, flexible packaging, sterile packaging, metal containers, aluminum foil, and flexographic printing. Hence, it has been demonstrated that these novel approaches can economically improve food safety and quality, decrease the microbial load of foodborne pathogens, and reduce food spoilage. This review study provides a comprehensive overview of the most common chemical or natural nanocomposites used in food packaging that can extend food shelf life, safety and quality. Finally, we discuss applying materials in the production of active and intelligent food packaging nanocomposite, synthesis of nanomaterial, and their effects on human health.

Kinetics of proteolysis in stored Mongolian cheese at ice-temperatures and split-split-plot analysis of storage factors affecting cheese quality

Mongolian cheese is non-fermented cheese, which easily deteriorates during storage because of hydrolysis. The freezing points of sucrose and sucrose-free cheese were measured -5.16 °C and -4.29 °C, respectively. Ice-storage temperatures of -2 °C and -4 °C were used and 0 °C was used as reference temperature. In this study, the changes of proteolytic indexes (PI) and total viable counts (TVC) of cheese at different ice-temperatures during storage were studied. The PIs of all treatments increased over storage time, which conformed to the Arrhenius first-order kinetic model. The shelf lives of sucrose and sucrose-free cheese were predicted. In addition, -4 °C effectively suppressed the increases in TVC and PIs. The split-split-plot design was applied in comparing the effects of cheese type, the storage time and storage temperature on PI. Storage time was the most important factor followed by cheese type and storage temperature.

Aging Studies on Food Packaging Films Containing β-Cyclodextrin-Grafted TiO2 Nanoparticles

Polymeric materials, such as polyvinyl alcohol (PVA) and ethylene–PVA copolymers (EVOH) are widely used in the food sector as packaging materials because of their excellent properties. TiO₂ nanoparticles (NPs) show photocatalytic activity; when added to the aforementioned polymers, on the one hand, they are expected to provide bactericidal capacity, whereas on the other hand, they could favor nanocomposite degradation. These types of nanoparticles can be derivatized with cyclodextrin macromolecules (CDs), which can act as food preservative carriers, increasing the packaging food protective properties. In this work, films containing β-Cyclodextrin (βCD)-grafted TiO₂ nanoparticles and PVA or EVOH were prepared. Regarding the photocatalytic activity of the nanoparticles and the possible environmental protection, accelerated aging tests for PVA, EVOH, and their composites with cyclodextrin-grafted TiO₂ nanoparticle (NP) films were performed by two methods, namely, stability chamber experiments at different conditions of temperature and relative humidity and UV light irradiation at different intensities. After analyzing the systems color changes (CIELAB) and Fourier transform infrared spectroscopy (FTIR) spectra, it was observed that the film degradation became more evident when increasing the temperature (25–80 °C) and relative humidity percentage (28–80%). There was no significant influence of the presence of CDs during the degradation process. When irradiating the films with UV light, the largest color variation was observed in the nanocomposite films, as expected. Moreover, the color change was more relevant with increasing NP percentages (1–5%) due to the high photocatalytic activity of TiO₂. In addition, films were characterized by FTIR spectroscopy and variation in the signal intensities was observed, suggesting the increase of the material degradation in the presence of TiO₂ NPs.

Biodegradable carboxymethyl cellulose based material for sustainable packaging application

The main goal of the present work was to develop a value-added product of biodegradable material for sustainable packaging. The use of agriculture waste-derived carboxymethyl cellulose (CMC) mainly is to reduce the cost involved in the development of the film, at present commercially available CMS is costly. The main focus of the research is to translate the agricultural waste-derived CMC to useful biodegradable polymer suitable for packaging material. During this process CMC was extracted from the agricultural waste mainly sugar cane bagasse and the blends were prepared using CMC (waste derived), gelatin, agar and varied concentrations of glycerol; 1.5% (sample A), 2% (sample B), and 2.5% (sample C) was added. Thus, the film derived from the sample C (gelatin + CMC + agar) with 2.0% glycerol as a plasticizer exhibited excellent properties than other samples A and B. The physiochemical properties of each developed biodegradable plastics (sample A, B, C) were characterized using Fourier Transform Infra-Red (FTIR) spectroscopy and Differential Scanning Calorimetry (DSC), Thermogravimetric analysis (TGA). The swelling test, solubility in different solvents, oil permeability coefficient, water permeability (WP), mechanical strength of the produced material was claimed to be a good material for packaging and meanwhile its biodegradability (soil burial method) indicated their environmental compatibility nature and commercial properties. The reflected work is a novel approach, and which is vital in the conversion of organic waste to value-added product development. There is also another way to utilize commercial CMC in preparation of polymeric blends for the packaging material, which can save considerable time involved in the recovery of CMC from sugarcane bagasse.

Nanotechnology application in food packaging: A plethora of opportunities versus pending risks assessment and public concerns

Environmental factors, oxidation and microorganisms contamination, are the major causes for food spoilage, which leads to sensory features alteration, loss of quality, production of harmful chemicals and growth of foodborne pathogens capable to cause severe illness. Synthetic preservatives, traditional conserving methods and food packaging (FP), although effective in counteracting food spoilage, do not allow the real-time monitoring of food quality during storage and transportation and assent a relatively short shelf life. In addition, FP may protect food by the spoilage caused by external contaminations, but is ineffective against foodborne microorganisms. FP preservative functionalities could be improved adding edible natural antioxidants and antimicrobials, but such chemicals are easily degradable. Nowadays, thanks to nanotechnology techniques, it is possible to improve the FP performances, formulating and inserting more stable antioxidant/antimicrobial ingredients, improving mechanical properties and introducing intelligent functions. The state-of-the-art in the field of nanomaterial-based improved FP, the advantages that might derive from their extensive introduction on the market and the main concerns associated to the possible migration and toxicity of nanomaterials, frequently neglected in existing reviews, have been herein discussed.

Sodium alginate with turmeric coating for ripened cheeses

Artisanal cheeses produced with high coliform counts are commonly on the market in several countries. The bioactive edible coating use appears as technological innovation in the dairy derivatives market to improve quality and increasing the products shelf life. The objective of this study was to evaluate the characteristics of cheeses produced with Lactobacillus helveticus containing high coliform counts and coated with tumeric and sodium alginate. The coatings were evaluated for mechanical properties, water steam permeability and sorption isotherm. The experimental design was completely randomized and the treatments consisted of sodium alginate and turmeric 1% (AGAT) edible cover and the other one without edible cover (SEMC), data were analyzed by the Proc GLM SAS 9.3 program.The coated cheeses had higher microbial growth although the total coliform bacteria were reduced according to the storage time. For instrumental color, there was no significant difference between treatments. Coverage significantly altered hardness, gumminess, chewiness and cohesiveness over time, while elasticity was not affected. The coating presence was not significant for water steam permeability and mechanical properties. The tested solution did not effectively improve microbiological quality, however, coated cheese samples showed increased lactic acid bacteria, water activity and improved cheese texture, making them softer, with less elasticity, cohesion and chewing.

Efficiency of Novel Antimicrobial Coating Based on Iron Nanoparticles for Dairy Products’ Packaging

The main function of food packaging is to maintain food’s quality and safety. The use of active packaging, including antimicrobial materials, can significantly extend the shelf life of food. Many of these packaging solutions are based on the application of polymer films containing metal nanoparticles (e.g., Ag, Au, Cu) or metal oxides (e.g., TiO2, ZnO, MgO). However, the use of iron nanoparticles is rarely mentioned. In the study, polylactide (PLA) films containing zero-valent iron (ZVI) were made by casting method. Pure PLA films and PLA films with the addition of Fe2O3 were used as comparative materials. The composition and structure of ZVI/PLA films were evaluated with scanning electron microscopy. The XRD spectra performed on ZVI/PLA films confirmed the presence of iron in the packaging material and revealed their oxide form (Fe2O3). The addition of zero-valent iron in the concentration 1%, 3%, or 5% resulted in the formation of crystallographic planes measuring 40.8, 33.6, and 28.6 nm, respectively. The color and gloss of the films, and their antimicrobial activity against bacteria (Bacillus subtilis, Escherichia coli, Staphylococcus epidermidis) and fungi (Geotrichum candidum, Rhodotorula rubra) were also examined. The PLA films with addition of 3% of ZVI (w/w) inhibited the growth of all tested organisms in contrast to PLA and PLA/Fe2O3 films. The addition of ZVI to polymer matrix caused changes in its appearance and optical properties. The ZVI/PLA coating used on polyolefin film allowed to extend the shelf life of goat cheese packed in examined material to 6 weeks. Considering the antimicrobial properties of the ZVI/PLA films and PLA biodegradability the obtained material can be successfully applied in the food industry.

The emerging role of metallic nanoparticles in food

Nanotechnology is widely used in biomedical applications, engineering sciences, and food technology. The application of nanocompounds play a pivotal role in food protection, preservation, and increasing its shelf life. The changing lifestyle, use of pesticides, and biological and/or chemical contaminants present in food directly affect its quality. Metallic nanoparticles (MNPs) are useful to develop products with antimicrobial activity and with the potential to improve shelf life of food and food products. Due to the prevention of microbial growth, MNPs have attracted the attention of researchers. Biopolymers/polymers can be easily combined with different MNPs which act as a vehicle not only for one type of particles but also as a hybrid system that allows a combination of natural compounds with metallic nanocompounds. However, there is a need for risk evaluation to use nanoparticles in food packaging. In this review, we aim to discuss how MNPs incorporated into polymers/biopolymers matrices can be used for food preservation, considering the quality and safety, which are desirable in food technology.

Utilization of chitosan/Ag bionanocomposites as eco-friendly photocatalytic reactor for Bactericidal effect and heavy metals removal

Chitosan is a nontoxic, eco-friendly, and biocompatible natural polymer which could be used in an extensive range of applications for example in the areas of membranes, biomedicine, hydrogels, wastewater treatment, food packaging. Moreover, chitosan based nanomaterials had high sorption capacities, chelating activities, stability, and versatility, that would be potentially applied as green reactants in various scientific and engineering applications. The current study involved the preparation of silver nanoparticles incorporated into chitosan thin films and used for various purposes including photo-oxidation of organic pollutants, heavy metal removal (Cd, Pb, Cr, and Fe) and antibacterial activity. The fabricated chitosan/silver (CS/Ag) bionanocomposites thin films were characterized by the ultraviolet-visible (UV-Vis) spectroscopy, transmission electron microscopy (TEM), and Fourier transforms infrared (FT-IR) spectroscopy. Furthermore, the prepared CS/Ag bionanocomposites had revealed good photodegradation rate, heavy metals removal and antimicrobial activity against gram-negative bacteria like E. coli, and gram-positive bacteria like G. bacillus, with increasing the loading of different concentrations of chitosan and silver nanoparticles incorporated into the prepared bionanocomposite thin films. Consequently, the prepared CS/Ag bionanocomposites are considered good candidates for wastewater treatment through photo-oxidation of organic pollutants, heavy metal removal as well as respectable antibacterial materials.

The Effect of Nanofillers on the Functional Properties of Biopolymer-based Films: A Review

Waste from non-degradable plastics is becoming an increasingly serious problem. Therefore, more and more research focuses on the development of materials with biodegradable properties. Bio-polymers are excellent raw materials for the production of such materials. Bio-based biopolymer films reinforced with nanostructures have become an interesting area of research. Nanocomposite films are a group of materials that mainly consist of bio-based natural (e.g., chitosan, starch) and synthetic (e.g., poly(lactic acid)) polymers and nanofillers (clay, organic, inorganic, or carbon nanostructures), with different properties. The interaction between environmentally friendly biopolymers and nanofillers leads to the improved functionality of nanocomposite materials. Depending on the properties of nanofillers, new or improved properties of nanocomposites can be obtained such as: barrier properties, improved mechanical strength, antimicrobial, and antioxidant properties or thermal stability. This review compiles information about biopolymers used as the matrix for the films with nanofillers as the active agents. Particular emphasis has been placed on the influence of nanofillers on functional properties of biopolymer films and their possible use within the food industry and food packaging systems. The possible applications of those nanocomposite films within other industries (medicine, drug and chemical industry, tissue engineering) is also briefly summarized.

A review on versatile applications of blends and composites of CNC with natural and synthetic polymers with mathematical modeling

Cellulose is world's most abundant, renewable and recyclable polysaccharide on earth. Cellulose is composed of both amorphous and crystalline regions. Cellulose nanocrystals (CNCs) are extracted from crystalline region of cellulose. The most attractive feature of CNC is that it can be used as nanofiller to reinforce several synthetic and natural polymers. In this article, a comprehensive overview of modification of several natural and synthetic polymers using CNCs as reinforcer in respective polymer matrix is given. The immense activities of CNCs are successfully utilized to enhance the mechanical properties and to broaden the field of application of respective polymer. All the technical scientific issues have been discussed highlighting the recent advancement in biomedical and packaging field.

Silver nanoparticles coated with dodecanethiol used as fillers in non-cytotoxic and antifungal PBAT surface based on nanocomposites

In the present study, we report the preparation of antifungal and non-cytotoxic polymer nanocomposites with potential application in biomedical materials. Dodecanethiol-protected silver nanoparticles (AgNPs-DDT) were synthesized by a reduction/precipitation method and dispersed in chloroform to obtain stable colloidal dispersions. PBAT-based nanocomposites containing 0.25, 0.5 and 2 wt% AgNPs-DDT were prepared by casting method. The incorporation of AgNPs-DDT in PBAT matrix resulted in nanocomposites which combine improved mechanical performance and antifungal properties with a non-cytotoxic characteristic.

Sol gel synthesis of hybrid chitosan/calcium aluminosilicate nanocomposite membranes and its application as support for CO2 sensor

Modification of chitosan with cross-linkers, blends with various kinds of polymers, nanoparticles and new organic-inorganic hybrid composites in order to obtain some improved properties attached more attention nowadays due to their good sensitivity in changing electrical and optical properties. In the current work modified hybrid chitosan/calcium aluminosilicate (CH/CAS) nanocomposite membranes and doped with (3, 5 & 7 mol%) Al₂O₃ nanoparticles were synthesized via sol-gel process in acidic conditions, which can be efficiently employed to capture CO₂ gas at lower and moderate temperatures. Furthermore, the fabricated CH/CAS nanocomposite membrane loading with (3, 5 & 7 mol%) Al₂O₃ were investigated using XRD, SEM, FTIR and dielectric measurements. The results indicated that the incorporation of Al₂O₃ in CH/CAS matrix significantly affected on the structural, dielectric and appeared good reliability for sensing CO₂ at atmospheric pressure. The dielectric behaviour for the prepared CH/CAS indicates that the dielectric constant (ε') decreases. According to XRD the introducing of Al₂O₃ leads to increase the crystallinity of the system and thus the dipoles of the system orient hardly with the applied field and results in lesser dielectric constant (ε'). Correspondingly, the CH/CAS nanocomposite membranes were characterized and its performance as CO₂ gas sensor was evaluated.

Degradable and Photocatalytic Antibacterial Au-TiO₂/Sodium Alginate Nanocomposite Films for Active Food Packaging

A degradable and antibacterial sodium alginate film containing functional Au-TiO₂ nanocomposites for food packaging was successfully developed. The Au-TiO₂ nanocomposites are synthesized hydrothermally and mixed with the alginate solution to form the film by a casting method. The Au-TiO₂ nanocomposites enable the film with excellent visible light absorption and transfer ability with the light absorption rang covering UV–visible wavelength (300–800 nm) and induce the increase of the film water contact angle from 40° to 74°, which contributes to the film shape stability. Furthermore, compared to the TiO₂ nanoparticle-incorporated film, the antibacterial ability of Au-TiO₂/sodium alginate composite film is improved approximately by 60% and 50% against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), respectively, in light conditions. The antibacterial property of the film arises from the increased production of reactive oxygen species (ROS) induced by the surface plasmonic resonance of Au nanoparticles. The degradable and antibacterial properties render the composite film of great application potential in food packaging industry.