films. Nisin acts as a depolarizing agent in bacterial membranes and creates pores in lipid bilayers. Nanofilm multilayer peptides intercalated different peptides charged at neutral pH, which was much more stable than when peptide film only stabilized electrostatic interactions.
There have also been records of nanoscale chitosan antibacterial action. A potential antimicrobial pathway includes interactions between the positive and the negative chitosan cell membranes, raising the membrane permeability and eventually contributing to the breakdown and leakage of intracellular content. The ineffectiveness of both rough chitosan and engineered nanoparticles at pH levels above 6 is consistent with observation given the lack of protonated amino groups [52].
1.9 Nano-scavenging Oxygen Film Used in Food or Eating Substances
Oxygen (O2) is responsible either directly or indirectly for the deterioration of many foods. For example, direct oxidation reactions lead to fruit browning and vegetable oils rancidity. Degradation of food by indirect action of O2 includes aerobic microorganism food spoilage. The inclusion of O2 scavengers in the food kit will also hold O2 rates very small, which are beneficial for many purposes because they will increase the food's life.
Successful production of oxygen scavenger films was achieved by applying titanium nanoparticles (TiO2) to different polymers, which are used to pack a wide range of oxygen-sensitive products. In particular, the emphasis was on the photocatalytic behavior of ultraviolet nanocrystalline titania. Since TiO2 acts by a photocatalytic mechanism, the requirement for ultraviolet absorption (UVA) light is its major drawback [53].
1.10 UV-Proof Processing of Foods Using Nanometal Oxides
The film based on nanocrystalline titanium (TiO2) is the commonly used material for UV absorption. During the exposure to sunlight, the effectiveness of TiO2-coated film exposure to sunlight inactivates TiO2 visible photo- catalytic absorption in the context of UV irradiation. Doping TiO2 with silver has been reported to have greatly improved photocatalytic bacterial inactivation. The resulting combination was good antibacterial properties of nanoparticles TiO2/Ag+ in a polyvinyl chloride (PVC) nanocomposite.
1.11 Nano-intelligent Food Labeling
In smart/natural, nanomaterials are used to monitor biochemical or microbial modifications in products, such as the identification of particular food contaminants or unique food spoilage markers. Nanoparticles may be used as reactive particles in packaging materials as regards smart packaging to notify the state of the packed product. To interact, warn, and classify the drug, the so-called nanosensors can respond to external stimulation adjustments to ensure its consistency and health. The latest innovations for smart food packaging polymer nanomaterials include spoilage triggers, oxygen markers, detection of items, and traceability [54].
1.12 Nanotechnology-Aided Freshness and Spoilage Indicators
The chemical interactions of nanosensors with spoilage components produced during the deterioration of food resulted in color change and state the level of freshness. The electrical, electronic, magnetic, and optical properties of polymers or electrically active conjugated polymers play an important role in chemical or electrical oxidation. Particularly electrochemical-polymerized conducting polymers may switch from oxidized (doped) to reduced (undoped) isolating state, which is the basis for many applications. The product indicator includes polyaniline film, which responds to several fundamental volatile amines released by noticeable colors during fish spoilage. Color variations were well linked in terms of overall volatile amine concentrations and microbial fish sample development rates in terms of the gross polyaniline (Milkfish) color variation [55].
Intelligent package has the potential to improve food safety and reduce food bone illness. Food spoilage is induced by microorganisms whose metabolism creates volatile compounds that can be identified by the conduction and/or recognition of micro-orientations dependent on gas emissions and food-freshness detections through performing polymer nanocomposites or metal oxides. Polymer nanocomposite-based sensors are used to conduct particles that are integrated into the polymer insulation matrix. The sensor resistance changes establish a pattern that adapts to the studied material. Conducting polymer nanocomposite sensors in black and polyaniline carbon were designed for the detection and identification of foodborne pathogens by producing a specific response pattern for each microorganism (for example, Salmonella sp., Bacillus parahemolyticus). For example, chicken freshness was analyzed based on the fragrance using a neural network to analyze metallic performance results such as tin and indium oxide gas sensors. In food packaging, a device that has several nanosensors, which are extremely susceptible to spoilage markers, creates a color change that indicates when the food is harmed.
1.13 Nanotechnology-Aided Oxygen Indicators in Food Industry
Metal nanoparticles can be easily used to generate oxygen and to cultivate aerobic microorganisms during the storage of food. There has been growing interest in developing nontoxic and irreversible sensors of oxygen in food-free, oxygen-free systems such as vacuum or nitrogen packaging. A UV colorimetric oxygen indicator was developed with UVA light that uses titania nanoparticles (TiO2) to photosensitize the reduction in polymer encapsulation of methylene blue by triethanolamine. The sensor bleaches through UV irradiation and stays colorless before oxygen is added to the initial blue light. The survival time is relative to the amount of access to oxygen [4, 56].
1.14 Application of Nanotechnology in Product Identification and Anti-counterfeiting
Nanoparticles can be used as some smart food packaging as a food safety tracking device or to avoid falsification. BioMerieux has developed the Food Expert ID® multi detection test for nano-monitoring responses to food scares. Nanobarcodes for individual objects or pellets were produced by the US Oxonica Inc., which must be interpreted using a modified microscope for anti-counterfeiting purposes. Commercially available nanobars are made of inert metals, such as nickel, platinum gold, and silver, by electroplating into templates that define the particle diameter, which then releases stripped nanorods from templates [1–4].
1.15 Usages of Nanotechnology in Traceability and Active Tags in Food and Drug Industry
Radiofrequency recognition usually involves package stickers in food and drug or pharmaceutical industries. The brands are electronic radio-frequency sensor-based mechanisms used for transferring data from a tag connected to an object and automated recognition of the object. RFID is an improvement on previous manual tracking systems or bar codes. It is extremely robust and can work at extreme temperatures and pressures and can be detected over 100 m, and many tags can be played at the same time. Nanotechnology also allows for cost-effective RFID tags in sensor packaging. Smaller, more compact nano-enabling tags may be placed on thin labels [1–3, 55]. It is a fact that when concerning public health, an evaluation of the possible migration into food of packaging components and an evaluation of their potential danger are critical for a thorough risk assessment. However, very little research has been conducted so far on the impact of nanomaterials on absorption or possible association of food contact materials with nanomaterial-dependent food components [56]. Thin film transistor is the key part of RFID tags, and it can be embedded in food packages; a researcher came upon with cheaper printable thin film transistor made up of carbon nanotube-filled inks. It can be easily printed on papers and plastics [57].
1.16 Conclusions
In the last ten years, nanotechnology offers enormous opportunities for creative food packaging technologies that favor customers and businesses alike. Even at an early stage of improvement of the material properties of packaging,
