Nanoparticles belong to the world of the infinitely small: their use is based on the knowledge and control of the nano-scale world. We have heard more and more about them over the past few decades, and their properties seem to have great benefits in various fields, and in particular that of food. What are these nanoparticles, and what are they for? The use of nano diamond comes every case.
An attempt to define:
Nanoparticles are very varied, in their forms, their chemical composition, and more generally their physical and chemical properties. There are also variations in their definition, and not all texts agree on this, the very definition of a nanoparticle and a nanomaterial. But the most commonly accepted definition concerns their size: as their name suggests, nanoparticles are microscopic particles, whose size is between 1 and 100 nanometers 1 nm is 10 -9 m; of size of a molecule.
The National Institute for Research and Security (INRS) distinguishes, in its dossier on this subject, the nanoparticles of nano-materials. A nanomaterial is a material of which at least one external dimension is nano-scale, that is to say approximately between 1 and 100 nm or which has an internal or surface structure at the nano-scale taken from the ISO TS 80004-1 standard, whereas a nanoparticle has its three dimensions at the nano-scale unlike, for example, carbon nanotubes, one of the three dimensions of which is not at the nanoscale. But this is not the definition adopted by the European Commission for example, which speaks of a threshold of 50% of nanoparticles to define a nanomaterial. The very definition of nanoparticles is therefore discussed.
A scale: the nanometer
According to expert, a CNRS researcher with whom we had an interview, there is no scientific reason to define nanoparticles in this way: why, for example, stop at 100 nm, why not 110, or 200? There is no real change in physical properties that would correspond to the threshold of 100 nm. But regulation needs a definition, hence the need to decide. Thus, the official definition adopted in this country is that of the European Regulation on Consumer Information on Foods (INCO), set up in 2011, to regulate in particular the declaration and labeling of nanomaterials.
Promising physicochemical properties:
Nano-materials have, by their very small size, particular physicochemical properties and different from classical substances. The Association of monitoring and civic information on the issues of nano-science and nanotechnology explains it on its website. Nanoparticles have a larger surface area i.e. the surface area of the actual surface, divided by mass or volume than conventional particles, which makes them more reactive as summarized by the Association Acting for the Environment in his press file: The principle is simple: the smaller a particle is, the more reactive it is. Materials can also acquire new properties at the nano-scale: for example, gold is totally inactive at the micrometric scale, while it becomes an excellent catalyst for chemical reactions when it takes nano-scale dimensions.
It is these properties that are exploited in the industry, in all areas: automotive, cosmetics and in particular, agro-food.
The many uses and benefits of nanoparticles in food
Nanoparticles used in food are in two ways: in the food itself, in particular, food additives, and in packaging. Each kind of nanoparticle has a specific role and improves the quality of the product in a broad sense: food and packaging in a certain way.