Pasteur revolutionized the food industry with the invention of the pasteurization process, which brought food production and processing down to the micron level.

When Watson and Crick discovered deoxyribonucleic acid (DNA) and conceived the DNA structure model at the level of 2.5nm, they reduced the human research perspective to the nanometer level and opened the door to the nanometer world of biotechnology, agriculture and food production, and the food industry completed the second revolution, and the real symbol of the arrival of the nanometer era of the food industry is the carbon nanotube-buckyball fullerene. The real symbol of the food industry’s nano era is the discovery of carbon nanotubes – Buckyball fullerene (C60), expanding the level of food production to the level of 1 nanometer.

Nano Related Concepts

Naturally occurring, engineering synthesis or accidentally generated, in the form of binding state, aggregation state or appendage form, and the form of one-dimensional or multi-dimensional size of 1nm ~ 100nm within the substance is called nanoparticles, as long as the internal composition or the surface containing nanoparticles of the substance that is nanomaterials; at the same time, one-dimensional or multi-dimensional size of 1nm or less in fullerene (C60), nanofibers, single-walled carbon nanotubes and graphene flakes are also special nanomaterials.

Nanotechnology is the science and technology based on the study of the special physical, chemical and biological properties and phenomena of nanomaterials, and the use of the special properties of nanoparticles to redesign, modify or assemble nanoparticles into new types of materials, devices or systems, etc. In short, “nanotechnology” is the science and technology of the world.

In a word, “nano” is not only limited to the measurement of space scale, but also provides a brand-new way of thinking for human beings to explore the unknown in science, which enables human beings to satisfy the needs of a higher level according to their own will from the more microscopic level of the objective world, so as to enhance the welfare of the human society.

As for nano-food, there is currently no precise definition in the international arena. According to the concepts of nanomaterials and nanotechnology, it can be seen that food products formulated by nanotechnology based on the raw materials of natural, synthetic or biogenic materials that are edible to human beings and in accordance with the needs of human body’s health and nutritional and dietary needs are nano-foods. From a broad perspective, as long as nanomaterials or nanotechnology are involved in the whole process of pre-production (agricultural production), production and processing, packaging, storage and transportation, the food produced can be called nanofood.

Since the existing scientific knowledge can not be fully assessed on the application of nanotechnology in the field of food, while nanofood contributes to the development of society, it also poses certain risks to human health, the biological environment, and the social and ethical order of the society, which to some extent has increased the heat of research on nanofood.

Food Applications – International Scope

With the development of nanotechnology, its application scope involves 1805 kinds of products in 37 fields of 8 industries, such as home appliances, automobiles, electronics, food (beverage), home gardening, etc.; its application in the field of food is also more extensive, in the period of 2009~2012, there are as many as 186 patents about nano-food, and 10% of the patents are related to food safety detection, 19% are related to nano-food 10% of the patents are about food safety testing, 19% are about nano-food additives, and 47% are about nano-packaging materials for food.

It can be seen that the application of nanotechnology in the food field mainly focuses on three aspects: food additives, food packaging materials and food safety testing.

From the perspective of food production chain, there are 4 links involving nanofood production:

First, the pre-production process of food production, mainly refers to the agricultural production process, which will be used to contain nanomaterials such as pesticides, fertilizers and other agricultural inputs, agricultural inputs in the agricultural products will have residues, and edible agricultural products are the raw materials for food production, so the process is the source of nanofood production;

Second, food processing, the process involves nano-food additives, nano-production equipment and technology;

Third, nano-food, i.e., food containing nano-particle components or packaging materials containing nano-particle components;

Fourth, food safety and detection process, using nanotechnology to synthesize specialized sensors to detect nano-components in food and safety.

In terms of specific types, at present, in the food market, from livestock to aquatic products, from eggs and milk to vegetables, from fresh products to manufactured products, can see the corresponding nano-food.

For example, milk containing nano-casein, meat with nano-cellulose, cookies with nano-silver, olive oil with nano-liposomes, and other food products that are closely related to public life.

According to the data and information on the website of Project on Emerging Nanotechnology (PEN) in the United States, as of November 2014, as many as 116 types of nanofoods have been developed globally, whereas there were only six types of nanofoods in the category of nanofoods in 2006 and before; nanofoods involve nanomaterials, mainly zinc oxide nanoparticles, nano-silicon dioxide, nano-silver, nano-gold, nano-copper, nano-cobalt, nano-magnesium, nano-calcium, nano-carbon materials, nano-fibers and other material materials. In addition, the origin of these nano-products shown in PEN website is mainly concentrated in EU member states, the United States, Japan and other countries and regions.

Application – Domestic Scope

The application of nanotechnology in the field of food science in China is still in the exploratory stage, however, China as a country in the world with faster development of nanotechnology, has developed and applied the number of products related to nano-food far more than 7, from the application of the development of the application of China’s nano-food is mainly embodied in the 3 aspects:

First, the development and application of nano-functional food.

The development of nano-functional food focuses on two fields, namely, nano-particle delivery system (functional food carrier system) and nutrient additives for functional food. The main purpose of functional food carrier is to enhance the absorption of nutrients by human body and prevent the oxidization and deterioration of docosahexaenoic acid (DHA), vitamins and other nutrients, and the specific applications include nano-microcapsule for lipid, nano-microcapsule for enzyme, and nano-microcapsule for enzyme. Specific applications include nano-microcapsules of lipids, nano-microcapsules of enzymes, nano-microcapsules of biologically active substances, e.g., nano-microcapsules of carotenoids, nano-microcapsules of DHA, nano-microcapsules of facultative amylase, etc. The technology of nanoemulsion embedding is also applied to the development of functional foods.

However, in view of the potential bio-toxicity of nanoemulsion, there are some limitations in the application of this technology; nano nutrient additives are a kind of nano-foods that nanosize essential trace elements and other substances, increase the direct absorption of trace elements in the intestine, and reduce the toxic side effects that may be produced by the interaction of trace elements in the human body, for example, nano-calcium, iron, zinc, selenium and so on, are applied in food.

The second is the nano-packaging materials for food.

At present, the domestic application of nano-packaging materials is mainly to reduce water absorption, antibacterial coatings, time-temperature indicators (in order to ensure the freshness and shelf-life of the temperature range that can withstand on the basis of); focused on nano-freshness preservation materials, nano-bacterial materials, nano-barrier materials in three areas; specific application to food preservation of nano-Ag freshness preservation materials, nano-tiO2 freshness preservation materials, nano-SiOx preservation materials, nano-molecular sieve preservation materials, nano-molecular sieve preservation materials, nano-molecular sieve preservation materials. materials, nano molecular sieve preservation materials and other types.

For example, PE/Ag2O nanopackaging bags can effectively reduce the decay rate of fruits and vegetables; nano TiO2 chitosan composite film can prevent the loss of VC in young ginger; nano SiOx freshness preservation fruit wax can reduce the hardness of apples while reducing the rate of weight loss of apples; ZnO nanoparticles and different polymers blended with different types of nano-antimicrobial materials, for example, the ZnO/PVC film can effectively suppress growth of bacteria such as E. coli in food, prolonging the shelf life of fresh food; in terms of nano-barrier materials, the more widely used is polyester nanoplastics, which can make dairy products, beer and other food products keep fresh taste for a longer period of time.

Third, nano food safety testing.

Nano-detection applications are mainly manifested in the development of biosensors based on nano-materials and the integration of nano-materials and traditional food safety detection technology in two aspects, covering the scope of sample pre-treatment, sensor preparation, detection and analysis of signal generation and other aspects of food safety detection.

Due to the high specificity of nanobiosensors, there are deficiencies in quantitative food safety detection, while the application is limited. In general, the technology of integrating nanomaterials in traditional food safety detection is more widely used, for example, carbon nanotubes, gold nanoparticles, quantum dots, magnetic nanomaterials, etc. are widely used in the detection of pesticide and veterinary drug residues, microorganisms, nitrites, phenolic compounds and heavy metals in water quality, and genetically modified foods.