Living is made easier by advances in nanoscience and nanotechnologies in nearly every scientific subject. It is a field that works with the combination of science, engineering, and technology that is conducted at the nanoscale, which is about 1 to 100 nanometers.
Nanotechnology is the application of extremely small things and can be used across all the other science fields, such as chemistry, biology, physics, materials science, and engineering. It’s difficult to imagine just how small the nanoparticles are and here are few examples for better understandings, a strand of human DNA is 2.5 nanometers in diameter, there are 25,400,000 nanometers in one inch and a single gold atom is about a third of a nanometer in diameter.
Necessity of Nanotechnology in Food Industry
Nanotechnology is an emerging, rapidly developing technology that ensures in the development of novel materials with potential applications. Nanomaterials are used in a variety of consumer, medical, commercial and industrial products. It is a promising research area with new innovation and community outreach.
Perishable food commodities like fresh fruits, vegetables, meat, poultry and its products are easy to spoil and a good carrier of human pathogens that leads to foodborne disease outbreaks, which draw public attention towards food safety. It provokes a demand to develop new antioxidant, antimicrobial nanomaterials, nutrient carriers, functional particles to preserve perishable food and to ensure food safety. Many researchers and industrialist are researching on novel nanomaterials with multiple functions that renders great potential for food and food-related industries. Applications in Food Processing The rising consumer concerns about food quality and health benefits are impelling the researchers and industrialist to find the way that can enhance food quality and nutritional value of the product. The demand of nanoparticle-based materials has been increased in the food industry as many of them contain essential elements and also found to be non-toxic.
They have been also found to be stable at high temperature and pressures. In food processing, theses nanostructures can be used as food additives, carriers for smart delivery of nutrients, anti-caking agents, antimicrobial agents, fillers for improving mechanical strength and durability of the packaging material.
Initially food industries have searched for a development of nanoparticles with effect to improve the flavor, color and texture of developed food products. Nanoparticles from TiO2, SiO2 and amorphous silica are used as food additives. TiO2 is also used as a coloring agent in the powdered sugar coating on doughnuts which is the pioneer of nanotechnology in food industries.
Then, the use of nanotechnology by the food and food-related industries is expected to increase, impacting the food system at all stages from food production to processing, packaging, transportation, storage, security, safety and quality. Later, more research were done on identification of nano-antimicrobial agents that can be added directly to foods or through antimicrobial packaging without any migration. The antimicrobial properties of nanomaterials like essential oils, organic acids, and bacteriocins that enables to preserve food during storage and transport.
Applications in Packaging Nanotechnology being applied in the formation of encapsulation, emulsions, biopolymer matrices, simple solutions, and association colloids offers efficient delivery systems to improve the quality of foods applied with nano-techniques. Nano polymers are trying to replace conventional materials in food packaging.
A number of nanocomposites, polymers containing nanoparticles, are used by the food industry for food packaging and food contact materials. Several researchers found the usage and application of various nanomaterials in food packaging. Many nanoparticles such as silver, copper, chitosan, and metal oxide nanoparticles like titanium oxide or zinc oxide have been reported to have antibacterial property that acts as active packaging as well as anti-microbial packaging.
Amorphous silica is used in food containers and packaging. Use of inert nanoscale fillers such as clay and silicate nanoplatelets, silica (SiO2) nanoparticles, chitin or chitosan into the polymer matrix renders it lighter, stronger, fire resistance, and better thermal properties. Engineered water nanostructures generated as aerosols are very effective at killing foodborne pathogens such as Escherichia coli, Listeria and Salmonella on steel food production surfaces.
The edible nano-coatings on various food materials could provide a barrier to moisture and gas exchange and deliver colors, flavors, antioxidants, enzymes, and anti-browning agents and could also increase the shelf-life of manufactured foods, even after the packaging is opened. Curcumin the most active and least stable bioactive component of turmeric (Curcuma longa) showed reduced antioxidant activity and found to be stable to pasteurisation and at different ionic strength upon encapsulation.
Applications in Packaging and Safety Nanomaterials used for food packaging provide many safety and functional benefits such as improved mechanical barriers, detection of microbial contamination and potentially enhanced bioavailability of nutrients. This is perhaps the most common application of nanotechnology in food and its related industries. Nanosensors is yet another boon to food safety that can be used for a variety of applications.
Commercial use of nanosensors has been reported to check storage conditions and during food transport in refrigerated trucks for temperature control. Biosensors based on carbon nanotubes also gained much attention due to their rapid detection, simplicity and cost effectiveness and have also been successfully applied for the detection of microorganisms, toxins, and other degraded products in food and beverages. Electronic tongue or nose is another novel invention to monitor and check the exact quality of foods at different temperature on consecutive days that consists of the array of nanosensors monitor the food condition by giving signals on aroma or gases released by food items
There are few studies that stress on unknown causes and query on safety measures to humankind because of nanotechnology in the form of nanomaterials and nanoparticles that is introduced directly in foods or in its packaging. Consumers are exposed to nanomaterials by consumption of food and beverages containing these extremely small particles of large reactive surface area of unknown safety.
Once absorbed in the gastrointestinal system, they may bioaccumulate in various organs of the body, leading to potentially adverse effects. Thus, application of nanotechnology by the food industry is of public concern. Public acceptance of food and food products containing nanomaterials depends on their perceived safety. This makes concern to formulate a standard and regulations in food industries to eliminate few hurdles and fear in application of nanotechnology in food products.
Advantages and Limitations Packaging Materials containing nanoparticles will resist and effective in foodborne pathogens which increases the shelf life of the food product through packaging. Packaging Materials containing nanomaterials have the potential of migrating from food packaging into food, so this technology still must demonstrate regulatory compliance before it gains wide-spread acceptance in the industry.
Future scope Nanomaterials are used as sensors to detect contamination and regulate the food environment. They can detect microbial and other food contaminants. Therefore, they are used as sensors in food production and at packaging plants. They can monitor the condition of food during transport and storage. More research to be done on material that is considered as GRAS (generally regarded as safe) substance, additional studies must be acquired to examine the risk of its nano counterparts because the physiochemical properties in nanostates are completely different from that are in macrostate.
The advances in nanotechnology are paving new paths day by day, there still persist many challenges and opportunities to improve the current technology and also issues about the consequences of nanotechnology that must need to be addressed in order to alleviate consumer concerns. The transparency of safety issues and environmental impact should be the priority while dealing with the development of nanotechnology in food systems and therefore compulsory testing of nano foods is required before they are released to the market.
Commercial applications of nanomaterials in the food industry will grow because of their unique and novel properties. Human exposure to nanomaterials will continue to increase. Therefore, the health impact of nanomaterials in food is of prime public concern. The ability to quantify the nanomaterial throughout the food life cycle is critical for manufacturing consistency, safety and potential benefits of the consumer product. US Food and Drug Administration (FDA) has issued a draft guidance for industry use of nanomaterials in animal feed.
However, more research is required to determine the impact of nanomaterials in food on human health to ensure public safety and improve public communication of the safe use of such materials in our food supply. Some test methods for nanomaterial safety assessment have been reported. However, no internationally accepted standard protocols for toxicity testing of nanomaterials in food or feed are currently available. Such protocols are in the development stage by organizations such as the International Alliance for Nano Environment, Human Health and Safety Harmonisation and US National Research Council. A uniform international regulatory framework for the evaluation of nanotechnology is a necessity for community acceptance and marketing.
(Dr Raajeswari is associate professor, Department of Food Science and Nutrition, Avinashilingam Institute for Home Science and Higher Education for Women, Coimbatore; Devatha is Ph.D Researcher, Department of Food Science and Nutrition, Avinashilingam Institute for Home Science and Higher Education for Women, Coimbatore)