1. Introduction

Nanotechnology is an emerging technology born at the end of the 20th century after the invention of the tunneling microscope in 1981. It is a technology that focuses on molecular research at a scale of 1~100 nanometers, and uses atoms or molecules to construct products with specific properties. Nanotechnology has a wide range of contents, including seven categories: nanosystem physics, nanochemistry, nanobiology, nanomaterials, nanoelectronics, nanofabrication, nanomechanics, etc., which are independent and interrelated, and together constitute an important milestone in the development of human history - from utilization to creation.

With the development of science and technology and the improvement of consumer requirements, nanotechnology enjoys an indispensable and important position in the development of human society. The food industry in particular, it has become a powerful force for change, aiming to provide innovative solutions to improve the quality, safety and shelf life of food. Nanotechnology is able to manipulate materials at the atomic or molecular level, enabling the creation of advanced materials that can significantly impact the way food is produced, packaged, and preserved. In particular, the addition of nanomaterials to food packaging can inhibit microbial growth, monitor food freshness, improve product durability, and directly address challenges such as food spoilage and waste [1].

Since the beginning of the 21st century, various nanomaterials have been developed, such as silver nanoparticles (AgNPs), which are widely used for their powerful antimicrobial properties, which help prevent the growth of harmful bacteria and prolong the freshness of food. Similarly, there is a growing interest in biocompatible and biodegradable nanomaterials, which provide environmental benefits by reducing plastic waste. However, while these innovations are promising, they also raise concerns about consumer health and environmental safety. Addressing these issues through rigorous testing and regulatory standards is essential for the sustainable and safe application of nanotechnology in the food industry. This article will explore the classification, structure, and function of nanomaterials in food applications, current advances in packaging, food additives, and safety monitoring, as well as the challenges and future directions for optimizing these technologies [2].

2. Classification, structure and function of nanomaterials

Nanomaterials have brought about epochal changes in all aspects of life, including food, clothing, housing, transportation, and cutting-edge technology. Biodegradable nanomaterials, for example, are biocompatible, tunable in performance, and have controllable activity in nanosystems, which are very suitable for use in the medical field [3]. These materials can be classified as inorganic, organic, and others, each with different uses in food technology.

2.1. Inorganic nanomaterials

Inorganic nanomaterials, such as titanium dioxide (TiO2), silicon dioxide (SiO2), and zinc oxide (ZnO), are commonly used in food packaging due to their strong antimicrobial and UV protection properties. For example, ZnO nanoparticles have strong antimicrobial activity and can inhibit the growth of bacteria on food surfaces, thereby extending the shelf life. Similarly, titanium dioxide effectively blocks UV rays and protects light-sensitive food ingredients from photodegradation, which helps maintain product quality.

2.2. Organic nanomaterials

Organic nanomaterials, including nanocellulose and PLA, are valued for their biocompatibility and potential health benefits. Plant-derived nanocellulose provides structural support and enhances the texture of food without being a health hazard. PLA is a recently popular biodegradable polymer that is widely used in packaging and food contact materials due to its non-toxic properties and ability to be safely absorbed by humans, compared to which these materials are more attractive to health-conscious consumers.

2.3. Other types of nanomaterials

Other types of nanomaterials, such as ceramic nanomaterials, biological nanomaterials, carbon-based nanomaterials and other materials. Among them, carbon-based nanomaterials are considered to be the most valuable materials due to their various allotropes of carbon. A typical example is graphene, which has properties as a smart nanomaterial for biomedical applications [4].

3. Application of nanomaterials in the food industry

The application of nanotechnology in the food field can be summarized into two categories, namely food nanostructure components and food nanosensing [5]. Applications in the food industry, including production, packaging and quality control, offer significant advantages over the past in terms of safety, freshness and sustainability.

3.1. Food Packaging

When it comes to food packaging, the two aspects of preventing movement and breathing are the most important topics. While there is no perfect solution, the advantages of nanomaterials over conventional materials are highlighted by their ability to limit the movement and permeability of gases to very low levels, which can greatly improve the preservation quality of food. Nanomaterials can enhance the functionality and durability of food packaging, and play a vital role in promoting the development of food packaging. Recent research has focused on further enhancing the durability, barrier, and antimicrobial properties of packaging.

3.1.1. Antimicrobial properties

Antibacterial nanomaterials, such as nano-silver and nano-zinc oxide, can inhibit microbial growth, reduce spoilage, and extend shelf life. For example, nanosilver can damage bacterial cell walls to prevent perishable food from spoiling, making it ideal for preserving fresh produce and dairy products. By integrating these materials into the packaging material, a high level of food safety and a relatively long shelf life can be guaranteed.

Freshness function

Nano packaging can prolong freshness by controlling oxygen and moisture content. Certain nanomaterials can form a barrier to regulate humidity within packaging, reduce oxidation, and preserve the taste and texture of food. Controlling freshness can also be achieved through smart packaging, which can control oxygen and moisture levels through sensors and determine if food has spoiled with sensors that detect pH [6]. These innovations reduce food waste through improved storage, while also providing real-time freshness indicator nanomaterials as food additives, providing innovative opportunities to enhance flavor, texture, and nutritional value.

3.2. Food additives

The use of nanomaterials as food additives is a pioneering practice. Edible nanocoatings are typically about 5 nanometers thick and can be used for all types of food products, not only as a packaging barrier, but also to enhance the flavor, texture, and even nutritional value of food products [7].

3.2.1. Nutritional enhancement

Nanomaterials can improve the nutritional value of food by ensuring safe delivery by improving the bioavailability of minerals and vitamins. For example, fat-soluble vitamins are encapsulated with nanomicelles to ensure their efficient transport in the body. This improves nutrient absorption, making it much more useful as a dietary supplement. In addition, nanoencapsulation technology also helps to protect and control the release of nutrients, thereby increasing their bioavailability.

3.2.2. Flavor and texture improvement

Nanomaterials can also enhance the flavor and texture of foods, acting as emulsifiers or thickeners. For example, nanoemulsions can provide consumers with smoother mouthfeel and stable texture of food, while nano-thickeners can produce a uniform consistency. These applications provide consumers with a better sensory experience and meet consumer preferences for high-quality, delicious food.

In addition, nanomaterials can be used as stabilizers to improve the consistency and organoleptic quality of food products and help provide solutions that make food choices healthier and more appealing.

3.3. Food safety testing

3.3.1. Nanosensors and nanodevices come into use

The use of nanosensors and nanodevices to monitor food quality in real time provides an innovative solution for real-time detection of food quality and revolutionizes the paradigm of food safety monitoring [8]. Nanosensors and nanoscale chips can be used to track a wide range of parameters, such as temperature, humidity, and contaminants in food. These sensors are able to detect small changes in the environment with greater accuracy than traditional methods. For example, nanoparticles can be functionalized to detect specific chemical or biomarkers to determine if food has spoiled or contaminated at an early stage. As a result, manufacturers and consumers can act quickly to keep food safe and reduce the risk of foodborne illness.

3.3.2. The improvement on sensitivity of detection

Nanotechnology can improve the sensitivity of detection systems to microbial and chemical contaminants [9], which are difficult to detect compared to traditional methods. Nanomaterials such as gold nanoparticles, carbon nanotubes, and quantum dots can be functionalized to identify and bind to specific target microorganisms or toxins. When these bound nanoparticles are incorporated into the biosensor, the signal generated by their interaction with the contaminant is amplified, thereby increasing the sensitivity and selectivity of the detection. As a result, even trace amounts of harmful substances can be detected quickly and accurately. This progress is critical to ensuring food safety and helping to prevent consumers from consuming food contaminated with pathogens, heavy metals, pesticides or other harmful substances.

4. Challenges and Optimization Solutions

While nanotechnology presents unprecedented opportunities for the food industry, there are still many challenges to its application. There are several issues that must be addressed in order to maximize its benefits and reduce risks.

4.1. Safety and Health Risks

4.1.1. Cumulative pathogenic risk of nanomaterials in humans

The use of nanomaterials in food packaging, processing, and sensors can raise serious safety concerns, especially the accumulation of nanoparticles in the human body. Some studies have shown that due to the biological activity of nanostructures, nanoparticles have the potential to penetrate biological barriers such as the skin, gastrointestinal tract, and blood-brain barrier and thus be deposited in organs such as the lungs, greatly increasing the likelihood of lesions [10]. Their small size and high surface area allow them to interact with cellular structures, which can lead to inflammatory responses, organ damage, or other adverse effects. Since nanoparticles accumulate over time, assessing their long-term effects on human health is an inevitable step.

4.1.2. Monitoring the migration of nanomaterials in food contact

How to safely migrate nanoparticles from food packaging materials into food is another significant issue that remains to be addressed [9]. Regulatory agencies such as the FDA and EFSA are working to develop guidelines for assessing the migration and bioavailability of nanomaterials. Advanced technologies, such as in vitro models and simulation studies, are being developed to assess the risk of nanoparticles being transferred from packaging to food to ensure that they do not pose a threat to consumer health. Continuous monitoring and testing of it is the best answer to minimize any potential health hazards associated with the migration of nanomaterials.

4.2. Environmental impacts

4.2.1. Polluting effects of nanomaterials on ecosystems

The environmental impact of nanoparticles is another major issue for nanotechnology in the food industry [11]. Most nanomaterials are non-biodegradable, and their accumulation in the environment may lead to long-term ecological pollution risks. For example, nanoparticles can enter soil, water, or air during waste disposal or food packaging leaks, causing microbial communities to be destroyed or entering the food chain, affecting wildlife and human health. To address the environmental impact of nanomaterials, the first thing that needs to be carefully considered is how to extend their life cycle from production to recycling.

4.2.2. Development of biodegradable nanomaterials

In order to reduce the impact on the environment, researchers are currently focusing on the development of biodegradable and environmentally friendly nanomaterials. Materials synthesized from biopolymers or natural nanoparticles have gradually become effective alternatives to traditional non-degradable nanomaterials. In addition, the development of "green nanotechnology" aimed at creating materials and processes that are least harmful to the environment is also on the agenda. Research is ongoing to address the major challenges often faced in maintaining particle structure, size, and yield, while remaining environmentally friendly. These eco-friendly alternatives can reduce the environmental footprint of nanotechnology in the food industry, leading to more sustainable practices.

4.3. Cost and Market Acceptance

4.3.1. The high cost of nanotechnology

One of the major reasons why nanotechnology is currently not widely adopted in the food industry is the high cost associated with its production. The synthesis and functionalization of nanoparticles, as well as the integration of nanomaterials into food safety and packaging applications, require significant capital investment. At present, these costs would significantly increase the price of food if it were put into actual production, making it difficult for small and medium-sized enterprises to bear the economic burden of adopting nanotechnology. However, as research advances and production scales expand, the cost of nanomaterials will decrease, and they will be accepted and applied by a wider range of industries [12].

4.3.2. Consumer perception and acceptance

Another major obstacle is the low consumer acceptance of the use of nanotechnology in food. Even though nanotechnology is nothing new, many people are skeptical about the safety of adding nanoparticles-containing additives in consumption, although it is true that their potential risks are not fully understood [13]. Gaining public acceptance plays a crucial role in the acceptance of new technologies, so transparent communication, regulation and oversight, and scientific research to educate the public about the benefits and safety of nanotechnology, while maintaining rigorous testing and certification, will help build trust in the minds of consumers and increase market acceptance.

5. Conclusion

Nanotechnology offers tremendous opportunities for the food industry, providing innovative solutions to improve food safety, quality and sustainability. The use of nanomaterials in food inspection and packaging can improve detection sensitivity, leading to faster and more accurate identification of contaminants. However, there are still challenges in addressing safety, environmental issues, and consumer acceptance. In order to realize the full potential of nanotechnology, it is essential to continuously study the health and environmental impacts of nanomaterials and develop more sustainable and environmentally friendly alternatives. Through continuous innovation and regulatory oversight, I believe that nanotechnology can revolutionize the food industry in the future, making it safer, more efficient, and more sustainable, and bringing a better experience to consumers.