Scientists have discovered that nano-sized biological and non-biological structures have valuable physical, chemical and biological properties that are substantially different from the larger forms from which they are made. Engineered nanomaterials (ENMs) are now used in medicine, information technology, nutrition, food processing and food safety, just to mention a few applications.
Although still in the emerging phases, global sales of ENM ingredients and finished products were estimated to be nearly US$17 billion in 2008 and are expected to grow 6.9 per cent annually over the next four years. Food applications are estimated to be about six per cent of global sales today, but are expected to outpace other nanotechnology (NT) applications.
As the name implies, nanotechnology is all about the science and technology of things small, specifically 1-100 nm in at least one dimension. A nanometer is 1/billionth of a metre. A molecule of DNA is about 1.6 nm in thickness. Life forms are essentially complex arrangements of different nanomaterials (NMs) working in synergy. NMs are not unique to life forms, and can be found everywhere in nature including volcanic dust.
Food applications are expected to bring a range of benefits to the industry including new flavours, textures, aromas, colours, fewer calories, novel nutrients, improved bioavailability for nutrients, easier processing, improved packaging, traceability and enhanced security. A variety of food ingredients, additives, carriers for nutrients and food-contact packaging materials are now available in some countries.
Sensory – Because of their minute size, ENMs have an enormous surface area and thus can absorb large quantities of flavours, aromatics and food colouring agents. ENMs can then be further engineered to release their absorbed ingredients on cue when a temperature, pH or other condition is attained. Nano-emulsions have been reported to mimic the texture of fats, enabling product developers to reduce the amount of fat without sacrificing eating quality. There are reports saying that NT can reduce salt levels in some applications and enhance smoothness in emulsions.
Nutrition – Both novel food ingredients and food supplements can be carried by ENMs which are incorporated into conventional food products. As already mentioned, these ENMs can be tailored to release their payload under different conditions and/or times. In addition to having a large surface area to carry bioactive ingredients, ENMs’ small size can enhance the bioavailability of the ingredients, making them a good vehicle for delivering nutrients.