Also the sector of materials for food packaging has seen many innovations connected to the progress of nano-technologies. In particular, recently there has been the development of the following materials:
• nano-compounds for the production of polymer nano-materials, made by introducing nano-particles in a polymer matrix. This approach is considered much better for obtaining polymer nano-materials compared with the production of polymer materials on a nano-metric scale;
• “active and intelligent” materials for food packaging able to release substances of nano-metric dimensions with antimicrobial and/or antioxidant properties. Some nano-materials show, besides the antimicrobial activity, also the possibility to have a common interface or a physical contact with the food surface and this is essential for the functionality of active materials packaging. Therefore, the combination of antimicrobial packaging materials with active nano-metric substances, is a new way to control the superficial microbial contamination of food, extend their preservation time, improve food quality and safety and, finally, also decrease the impact of waste deriving from food packaging. In addition to the above mentioned applications, intelligent packaging on a nano-metric scale, also include nano-sensors, which can communicate to the consumer information on the food they contain;
• the nano-metric fillers can improve the barrier properties of the material where they are contained and so reduce the deterioration and contamination effects of the product.
From what has been seen, it is clear that the progress on nanotechnologies can be an advantage not only for food industries but also for all the sectors connected to food and therefore it is desirable to have a greater diffusion in nanotechnologies at an industrial level. Even if there are many advantages in the use of nano-technologies, it is necessary to keep into consideration the possible negative implications of their use in the food sector and the importance of investigations on health and the possible implications on the environment should not be under evaluated. Nano-particles which come into contact with the human body both intentionally and by chance, have such small dimensions to potentially reduce the efficacy of the barriers of the human body to the penetration of foreign bodies and to their movement inside the body. Therefore, there is a growing concern that the use of nano-materials in the food industry could cause the access of nano particles into the tissues, with a related accumulation of toxic contaminants to the detriment of human health. For this reason, it could be useful to divide the nano packaging into 2 big groups, distinguishing packaging for which the migration of nano-particles into food products is intentional, from packaging for which the migration of nano particles is not necessary or is unwanted. It is reasonable to foresee that the first type of packaging will develop less than the second, because it will be subject to higher restrictions and probably also to a more negative perception from consumers. For all these reasons, before commercializing nano-technologies in packaging, it will be necessary to evaluate the toxicity and the bio-accumulation of these substances, and then proceed to the evaluation of risks related to the exposure and finally outline the rules connected to their use.
Bibliography
M. Cushen, Trends in Food Science & Technology 24, 2012, 30
