Nanotechnology and food safety

Today, the role of nanotechnology in human life is undeniable as a broad range of industries, particularly food and medicine sectors, have been dramatically influenced.

Nanomaterials can contribute to food safety by forming new nano-sized ingredients with modified physicochemical characteristics. Nanotechnologies can inhibit the growth of food spoilage microorganisms by recruiting novel and unique agents that are involved in removal of microbes from foods or prevent adhesion of microbial cells to food surfaces. Hence, nanotechnology could be considered as a high-potential tool in food packaging, safety, and preservation. Moreover, the prevention of biofilm formation by disturbing the attachment of bacteria to the food surface is another useful nanotechnological approach.

Recently, nanoparticle-based biosensors have been designed and developed to detect the foodborne pathogens and hazardous substances through complicated mechanisms. During the past half-century, many methods such as freeze-drying and spray drying have been employed for increasing the viability in food industries; however, the other novel approaches such as encapsulation methods have also been developed. Admittedly, some beneficial bacteria such as probiotics bring diverse benefits for human health if only they are in a sufficient number and viability in the food products and gastrointestinal tract (GI).

Encapsulation of these valuable microbial strains by nanoparticles improves the survival of probiotics under harsh conditions such as extreme levels of temperature, pH, and salinity during the processing of food products and within the GIT tract. The survival and effectiveness of encapsulated microorganisms depends on different factors including function of cell wall components in bacteria and type of coating materials.

Application of Nanotechnology for Food Safety

• Detection of Harmful Substances in Food

Nanosensors are advantageous for food factories as they have great potential to quantify and detect low concentrations of organic compounds, pathogens, and other chemicals. Also, these devices can indicate fast response, high sensitivity, as well as recovery and integrate arrays on a large scale. For example, nanosensors are used for detection of organophosphates (originating from pesticides) in water and fruits.

There are many merits regarding the utilization of nanosensors in the food technology category, for instance, low costs, and portable instrumentation with quick responses, high sensitivity (low detection limits) and excellent sensitivity.

Nano-cantilever is the most recent type of nanosensors which has emerged as the fundamental components of the micro (nano)-electromechanical systems such as nanomechanical-based mass sensors. The main core of these nanosensors is composed of substances derived from small pieces of silicon that are able to detect microbial pathogens and toxic proteins in food. While the specific biomolecular interactions happen between a target in solution and receptor immobilized on the surface of a nanocantilever, a mechanical bending on the nanocantilever arises as a result of a change in surface stress, mass, optical angle, and frequency, which converts biochemical interactions into a concentration-dependent nano-mechanical response of the nanocantilevers.

Safety Points in Food Nanotechnology

Recently, many industries have been dramatically affected by nanotechnology; as a result, the market of products containing nanoparticles has experienced a considerable growth. Along with different merits of nanotechnology in food science like fast reproduction, the other issues such as ethical, regulatory, and policy points as well as public and environmental safety issues have also been raised.

Nanomaterials can show substantially various biological and physicochemical characteristics compared to their respective bulk counterparts, and these unknown characteristics create unpredictable risks. Despite numerous studies in this area, the consequences of direct contact of oral intake and nanomaterials in humans remain unclear and need further risk assessment.