Using nanotechnology and cellulose to make bio-based packaging material for the food industry
Schema of food packaging test by contact (a); food simulation after 5 days, with TOCN film (b), TOCN/PVA-PPy (c); schema of food packaging test by noncontact (d); food simulation flasks ( left: TOCN/PVA-PPy and right: TOCN/PVA films) (e); piece of banana after 5 days (f).
Scientists at the Renewable Materials Research Centre at the Université du Québec à Trois-Rivières (CRMR-UQTR) are conducting studies looking at the feasibility of producing bio-based packaging using cellulose-based nanomaterials obtained from Kraft wood pulp, polypyrrole and polyvinyl alcohol that would have antibacterial and antioxidant properties necessary for food preservation.
Non-perishable food packaging should prolong shelf life while providing protection from, among other things, dirt, oxygen, moisture and microbial degradation. In addition, the increasing environmental preoccupations of consumers are pushing industry towards the development of environmentally friendly “green” packaging. The type of composite packaging studied at CRMR-UQTR would incorporate the gas barrier and “green” properties (biodegradable) of cellulose with the antioxidant and antibacterial properties of polypyrrole. The hydrophobic nature of the polypyrrole also makes it possible to preserve the cellulosic material against moisture and thus to maintain the good mechanical properties of the packaging over time. A nanocellulose fibre gel, composed of micro and nanofibers, was produced using TEMPO oxidation and sonication treatments of bleached Kraft wood pulp and mixed with polyvinyl and dried to produce a film which was then coated by polypyrrole layer and then dried. The resulting packaging material was then subjected to various tests to evaluate its structural, barrier and antibacterial properties. Results look quite promising.
For more information, consult these articles: Article 1, Article 2.