Vapor Barrier Properties and Mechanical Behaviors of Composite Hydroxypropyl Methylcelluose/Zein Nanoparticle Films

Development and characterization of cellulose nanofiber reinforced hydroxypropyl methylcellulose films functionalized with propolis-loaded zein nanoparticles and its application for cheddar cheese storage

Cellulose nanofiber (CNF) reinforced hydroxypropyl methylcellulose (HPMC) films were functionalized with propolis-loaded zein nanoparticles (ZNP) to develop active, printable, and heat-sealable films. The films with 0, 0.10, 0.25, 0.50, or 0.75 mg/mL propolis-loaded ZNP, named 0ZNP, 0.10ZNP, 0.25ZNP, 0.50ZNP, and 0.75ZNP, respectively, were characterized for their mechanical, physicochemical, structural, functional and optical properties and antioxidant activity. The addition of propolis-loaded ZNP did not change tensile strength (P > 0.05), but increased elongation at break (from 24.72 to 36.58 %) (P < 0.05) for 0.25ZNP film. A water contact angle increased significantly (P < 0.05) for 0.50ZNP (~45 %) and 0.75ZNP (~137 %) films. The 0.25ZNP and 0.75ZNP films were evaluated for packaging cheddar cheese under refrigerated storage for 30 days, and resulted in comparable water activity, pH, titratable acidity, and lipid oxidation (P > 0.05) with those packaged by LDPE film and vacuum package. The developed films can function as eco-friendly alternatives to single-use plastic food packaging.

Application of nanotechnology in food: processing, preservation, packaging and safety assessment

Even though nanotechnology is extensively applied in agriculture, biochemistry, medicine and many other sectors, it is a developing field that conforms to new and more complex applications in food systems as compared to other technologies. It offers a viable strategy for integrating cutting-edge technology into a wide range of operations related to the production, development, fabrication, packaging, storage and distribution of food. The most fundamentally sophisticated technology in nano-based food science, nanoparticles deal with a wide range of nanostructured materials and nano methods, including nanofood, nanotubes, nanocomposites, nano packaging, nanocapsules, nanosensors, liposomes, nanoemulsions, polymeric nanoparticles and nanoencapsulation. This method is developed to increase food solubility and shelf life, availability of bioactive chemical, the protection of food constituents, nutritional supplementation, fortification and food or constituent delivery. Additionally, it serves as an antibacterial agent by generating reactive oxygen species (ROS) which cause bacterial DNA damage, protein denaturation and cell damage. Although the use of nanotechnology in food applications is advancing, there are certain negative or dangerous effects on health related to the toxicity and dangers of ingesting nanoparticles in food. The use of nanotechnology in the food industry, notably in processing, preservation and packaging, with its promising future, was addressed in this study. The toxicity of nanoparticles in food as well as its development in food safety assessments with certain areas of concern were also reviewed.

Recent progress in using zein nanoparticles-loaded nanocomposites for food packaging applications

Biopolymers are important due to their exceptional functional and barrier properties and also their non-toxicity and eco-friendly nature for various food, biomedical, and pharmaceutical applications. However, biopolymers usually need reinforcement strategies to address their poor mechanical, thermal, and physical properties as well as processability aspects. Several natural nanoparticles have been proposed as reinforcing agents for biopolymeric food packaging materials. Among them, zein nanoparticles (ZNPs) have attracted a lot of interest, being an environmentally friendly material. The purpose of the present review paper is to provide a comprehensive overview of the ZNPs-loaded nanocomposites for food packaging applications, starting from the synthesis, characteristics and properties of ZNPs, to the physicochemical properties of the ZNPs-loaded nanocomposites, in terms of morphology, permeability, solubility, optical features, hydrophobic/hydrophilic behavior, structural characteristics, thermal features, and mechanical attributes. Finally, at the end of this review, some considerations about the safety issues and gastrointestinal fate of ZNPs, as well as the use of ZNPs-based nanocomposites as food packaging, are reported, taking into account that, despite the enormous benefits, nanotechnology also presents some risks associated to the use of nanometric materials.

Development of xanthan gum/hydroxypropyl methyl cellulose composite films incorporating tea polyphenol and its application on fresh-cut green bell peppers preservation

The aim of this work was to develop an edible packaging material with good performance that can be used for fresh-cut vegetables preservation. The xanthan (XG)-hydroxypropyl methylcellulose (HPMC)-tea polyphenols (TP) composite film (XHT) was prepared by adding TP to the composite film-forming solution of XG and HPMC. At optimum TP dosage of 6% (XHT6), the tensile strength and elongation at break were at the maximum. The antioxidant activity and antibacterial properties were also enhanced, demonstrated good inhibitory ability to Staphylococcus aureus. After 8 days, the amount of Vitamin C that was retained by XHT6 was 127.81% and 7.83% higher than unpackaged and XHT0, respectively. Additionally, the MDA content in green peppers were 39.16% and 78.87% higher than that of unpackaged and XHT0, respectively. Practical applications of XHT films in preserving fresh-cut bell peppers had also shown positive results, making it possible as potential food packaging.

Cellulose Hydrogels Containing Geraniol and Icaridin Encapsulated in Zein Nanoparticles for Arbovirus Control

The most important arboviruses are those that cause dengue, yellow fever, chikungunya, and Zika, for which the main vector is the Aedes aegypti mosquito. The use of repellents is an important way to combat mosquito-borne pathogens. In this work, a safe method of protection employing a repellent was developed based on a slow release system composed of zein nanoparticles containing the active agents icaridin and geraniol incorporated in a cellulose gel matrix. Analyses were performed to characterize the nanoparticles and the gel formulation. The nanoparticles containing the repellents presented a hydrodynamic diameter of 229 ± 9 nm, polydispersity index of 0.38 ± 0.10, and zeta potential of +29.4 ± 0.8 mV. The efficiencies of encapsulation in the zein nanoparticles exceeded 85% for icaridin and 98% for geraniol. Rheological characterization of the gels containing nanoparticles and repellents showed that the viscoelastic characteristic of hydroxypropylmethylcellulose gel was preserved. Release tests demonstrated that the use of nanoparticles in combination with the gel matrix led to improved performance of the formulations. Atomic force microscopy analyses enabled visualization of the gel network containing the nanoparticles. Cytotoxicity assays using 3T3 and HaCaT cell cultures showed low toxicity profiles for the active agents and the nanoparticles. The results demonstrated the potential of these repellent systems to provide prolonged protection while decreasing toxicity.

The safety of nanomaterials in food production and packaging

Nanotechnology involves developing, characterising, and applying structures ranging in size from 1 to 100 nm. As a key advanced technology, it has contributed to a substantial impact across engineering, medicine, agriculture and food. With regards to their application in food, nanomaterials posses the ability to lead the quantitative and qualitative development of high-quality, healthier, and safer foods by outperforming traditional food processing technologies for increasing shelf life and preventing contaminations. Although rapid progress has been made in nanotechnology in food products, the toxicity of nanoparticles and nanomaterials is not very well known. As a result, nanomaterials are potentially toxic, therefore, considering the constantly increasing employment in food science, they need to be further characterised, and their use must be better regulated. We may face a crisis of nanotoxicity if the molecular mechanisms by which nanoparticles and nanomaterials interact with food and within living organisms is not fully understood. Food safety can be guaranteed only if we are thoroughly aware of nanomaterial properties and potential toxicity. Therefore, it is urgently necessary to have in the food sector a regulatory system capable of managing nanofood risks and nanotechnology, considering the health effects of food processing techniques based on nanotechnology. This present review discusses the impact and role nanotechnology play in food science. The specific application of Nanomaterials in food science, their advantages and disadvantages, the potential risk for human health and the analysis to detect nanocomponents are also highlighted.

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Nanotechnology can be used in food and feed processing at any level.

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Nanocomposite materials have been used in active packaging to prevent the passage of oxygen, carbon dioxide, and moisture into the food.

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Nanomaterials must be used with caution because they have the potential to cause toxic effects.

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Nanomaterials can travel deeper into the nucleus of cells and damaging the DNA.

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Analytical methods are required to reliably detect and characterize nanoparticles.

Measuring the concentration of protein nanoparticles synthesized by desolvation method: Comparison of Bradford assay, BCA assay, hydrolysis/UV spectroscopy and gravimetric analysis

The desolvation technique is one of the most popular methods for preparing protein nanoparticles for medicine, biotechnology, and food applications. We fabricated 11 batches of BSA nanoparticles and 2 batches of gelatin nanoparticles by desolvation method. BSA nanoparticles from 2 batches were cross-linked by heating at +70 °C for 2 h; other nanoparticles were stabilized by glutaraldehyde. We compared several analytical approaches to measuring their concentration: gravimetric analysis, bicinchoninic acid assay, Bradford assay, and alkaline hydrolysis combined with UV spectroscopy. We revealed that the cross-linking degree and method of cross-linking affect both Bradford and BCA assay. Direct measurement of protein concentration in the suspension of purified nanoparticles by dye-binding assays can lead to significant (up to 50-60%) underestimation of nanoparticle concentration. Quantification of non-desolvated protein (indirect method) is affected by the presence of small nanoparticles in supernatants and can be inaccurate when the yield of desolvation is low. The reaction of cross-linker with protein changes UV absorbance of the latter. Therefore pure protein solution is an inappropriate calibrator when applying UV spectroscopy for the determination of nanoparticle concentration. Our recommendation is to determine the concentration of protein nanoparticles by at least two different methods, including gravimetric analysis.

Investigation of food microstructure and texture using atomic force microscopy: A review

We review recent applications of atomic force microscopy (AFM) to characterize microstructural and textural properties of food materials. Based on interaction between probe and sample, AFM can image in three dimensions with nanoscale resolution especially in the vertical orientation. When the scanning probe is used as an indenter, mechanical features such as stiffness and elasticity can be analyzed. The linkage between structure and texture can thus be elucidated, providing the basis for many further future applications of AFM. Microstructure of simple systems such as polysaccharides, proteins, or lipids separately, as characterized by AFM, is discussed. Interaction of component mixtures gives rise to novel properties in complex food systems due to development of structure. AFM has been used to explore the morphological characteristics of such complexes and to investigate the effect of such characteristics on properties. Based on insights from such investigations, development of food products and manufacturing can be facilitated. Mechanical analysis is often carried out to evaluate the suitability of natural or artificial materials in food formulations. The textural properties of cellular tissues, food colloids, and biodegradable films can all be explored at nanometer scale, leading to the potential to connect texture to this fine structural level. More profound understanding of natural food materials will enable new classes of fabricated food products to be developed.

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.

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.

Effect of the application of an edible film with turmeric (Curcuma longa L.) on the oxidative stability of meat

The aim of this study was to develop an edible alginate-based film produced with turmeric (EFT), as an active compound, and evaluate its antioxidant capacity for application in fresh pork loin, beef loin, and chicken breast. The EFT was characterized by barrier parameters, color, and mechanical, structural, and antioxidant properties. Meat samples with and without EFT were stored at 4°C and analyzed at 2-day intervals. The meat samples with EFT showed significant differences (p < .05) in color (CIE L*a*b*) and exhibited lower TBARS values compared with those without EFT. The addition of turmeric in the film, besides affecting its physicochemical and structural properties, contributed an important antioxidant effect for the meat.

Effect of bovine bone collagen and nano-TiO2 on the properties of hydroxypropyl methylcellulose films

Hydroxypropyl methylcellulose (HPMC) film containing bovine bone collagen (BC) and nano-TiO2 were developed via casting method. The films were characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR), and their mechanical properties, barrier properties, thermal stability and surface color were investigated. The results showed that polymer matrices of HPMC and BC had good compatibility. The nano-TiO2 could be well embedded and dispersed in the matrix of HPMC/BC films, resulting in homogeneous, continuous and compact structure of the composite films. The addition of BC and nano-TiO2 significantly (p < .05) changed the surface color parameters of the films (p < .05). In addition, the introduction of BC and nano-TiO2 had a positive effect on the improvement of mechanical properties, barrier properties and thermal stability of the HPMC based films. The results suggest that HPMC based films containing BC and nano-TiO2 are more suitable for active packaging in the food industry.

Effect of various additives on the properties of the films and coatings derived from hydroxypropyl methylcellulose-A review

Edible films and coating materials are commonly used as appropriate packaging materials to extend the shelf life of fresh food. Due to all their properties, edible film and coating materials have been received much attention. They are biodegradable, edible, and good barrier against environmental parameters; thereby, they could carry and deliver food additives protecting food quality. Hydroxypropyl methylcellulose (HPMC), a cellulose derivatives, can act as an excellent film-forming agent for coating food produces. The aim of this study was to provide an overview of the HPMC properties and investigate the effects of various additives on its film-forming properties, such as rheological behavior, water vapor, and gas permeability, as well as mechanical, optical, antioxidant, and antimicrobial properties, with a focus on the recent progress and outputs, which has been recently published. Hydroxypropyl methylcellulose is prone to be commonly used as an advanced film-forming and coating materials for the sake of well miscibility with a wide range of organic and inorganic materials. However, this polymer requires further improvements regarding moisture susceptibility and thermal properties.

Recent Developments in Food Packaging Based on Nanomaterials

The increasing demand for high food quality and safety, and concerns of environment sustainable development have been encouraging researchers in the food industry to exploit the robust and green biodegradable nanocomposites, which provide new opportunities and challenges for the development of nanomaterials in the food industry. This review paper aims at summarizing the recent three years of research findings on the new development of nanomaterials for food packaging. Two categories of nanomaterials (i.e., inorganic and organic) are included. The synthetic methods, physical and chemical properties, biological activity, and applications in food systems and safety assessments of each nanomaterial are presented. This review also highlights the possible mechanisms of antimicrobial activity against bacteria of certain active nanomaterials and their health concerns. It concludes with an outlook of the nanomaterials functionalized in food packaging.