Tuesday, January 13, 2009


Nanotechnology based on highly reactive particles of sizes less than 100 nano meter is predicted to be central to developing and using new electronics and energy technologies during the present century. Properties of nano particles are not governed by the same physical laws as larger particles but by quantum mechanics. Their physical and chemical properties such as color, solubility, strengths, chemical reactivity and toxicity can be quite different. Engineered nano particles are used in hundreds of commercial products that are marketed to day which include transparent sun screens, light diffracting cosmetics, penetration enhanced moisturizers, stain and odor repellent fabrics, dirt repellent coatings, long lasting paints & varnishes and many others.

A nano meter (nm) sized particle measures one billionth of a meter and one can imagine how small it is when a human hair measures 80,000 nm! A DNA strand is 2.5 nm wide while a protein chain is 5 nm in diameter. Nano technology has already made inroads into food industry and it is claimed that more than 300 foods have already been developed with this technology. The market value for nano foods is estimated to increase to more than $ 20 billion by 2010 and it is predicted that more than 40% of food products will be nano technology based by the year 2015. Nano technology can confer unique advantages on processed foods in many ways. Programmable foods, considered the ultimate dream of the consumer will have designer food features built into it and a consumer can make a product of desired color, flavor and nutrition using specially programmed microwave ovens. The trick is to formulate the food at the manufacturer's end with millions of nano particles of different colors, flavors and nutrients and under the program in the oven set by the consumer based on his preferences, only selective particles are activated while others stay inert, giving the desired product profile. Nano based polymers with silica based nano particles sandwiched can enhance the properties of pressure sensitive adhesive labels and create biodegradable properties in them. Enhanced solubility, improved bio-availability, facilitating controlled release and protecting the stability of micro nutrients in food products are other virtues of nano technology. According to MFPI Minister, GOI is setting up a National Nano Science and Technology Institute to develop nano foods by using nano technology during cultivation, processing and packaging of food but it is not clear whether the declaration has any backing of the GOI or whether any serious planning has really gone into the proposal.

How about a butter with low fat but tasting and feeling like natural butter? Nano technology bluffs believe it is possible in future using this powerful technique. Similarly one can make milk taste like cola beverage so that youngsters will have less inhibition in consuming nutritious milk. Foods can be enriched with fruits and vegetables through nano technology to deliver higher nutrient density in such foods. Nano scale food components can be encapsulated and mixed with other foods in novel combinations. This technology is also seems to be useful in dissolving additives like vitamins, minerals, anti oxidants, phytochemicals, nutritious oils which are not normally soluble. Nano particles can make many products clear which other wise are opaque or translucent. Nano adhesive properties can bind to harmful matters in the GI tract and remove them without any harm. Pure silver colloid liquid, reduced to one nano meter size with atomic particles is highly bactericidal, capable of achieving 99.9% kill against 650 species of microorganisms within 6 minutes while a normal antibiotic is effective only against 5-6 species. There are containers being offered with coatings of nano silver particles which can be used for storage of foods safely without spoilage. Use of nano technology as a sensor to detect food spoilage within a packet of processed food is fraught with great significance in our fight against pathogenic microorganisms.

While consumer will be thrilled at the enormous range of exciting food products emerging by application of nano technology, like any other new technologies, serious questions about safety will be an issue requiring attention by the industry as well as the policy makers. The GRAS list of additives universally accepted will have to be reexamined when used at nano scale level. Rats breathing nano particles showed a tendency to collect them in the brain and the lungs increasing the bio markers for inflammation and stress response. Toxicity is one issue which will be upper most in the minds of the consumer and since nano particles are more reactive, more mobile and likely to be more toxic, this concern must be addressed. There is strong possibility that nano particles in the body can result in increased oxidative stress which, in turn, can generate free radicals leading to DNA mutation, cancer and possible fatality. If irradiation technology has taken more than 5 decades of research and safety assessment before becoming acceptable in a limited way, nano technology also can wait till all safety issues are resolved.


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