The researchers looked at cellulose nanocrystals (CNC) to see if they could be adapted for the potential of being used in food packaging. They found that it is possible by adding the right ingredients on a cellulosic level. This is an important step in the transition to environmentally-conscious packaging for a more sustainable world.
UMaine is one the world’s leading researchers of cellulose nanocomposites such as cellulose nanocrystals (CNC), cellulose nanofibers (CNF), and tempo-oxidized cellulose nanofibers (TOCN). These materials can be used in a variety of applications, such as fiberglass, strengthening wood cells, and now possibly even food packaging. This is especially amazing because they are a renewable and sustainable resource that is biodegradable, nonpetroleum based, carbon-neutral, with low environmental, animal/human health, and safety risks. Read more about cellulose nanocomposites at UMaine and the ASCC.
Tunable biocomposite films fabricated using cellulose nanocrystals and additives for food packaging
Cong Chen, Dr. Wenjing Sun, Dr. Jinwu Wang, Dr. Douglas J. Gardner
Cellulose nanocrystals (CNCs) are considered a prospective packaging material to partially replace petroleum-based plastics attributed to their renewability, sustainability, biodegradability, and desirable attributes including transparency, oxygen, and oil barrier properties. However, neat CNC films are rigid and too brittle to handle or utilize for packaging applications. Hence different additives, including sorbitol, polyvinyl alcohol (PVA), chitin, and κ-carrageenan (CG) were selected to mix with CNCs for packaging film preparation. The influence of additive categories (plasticizer, nonionic polymer, weak cationic and anionic natural polysaccharide), and their concentrations on the performance of CNC suspensions as well as optical, barrier, mechanical, and thermal properties of CNC films were examined. The morphology and physical characterization including density, equilibrium moisture content, contact angle and water durability of the composite films were also determined. Sorbitol and PVA films had the best visible light transparency; mixing with chitin can effectively improve the water durability of CNC films, and CG changed the CNC film from hydrophilic to hydrophobic. Moreover, all CNC films exhibited sufficient oxygen barrier properties, high PVA content films attained the “very high” barrier grade. Thus, durable CNC films can be obtained by adding proper types and amounts of additives, which provides potential scenarios for practical application of CNC films in food packaging.