Recent advances in cellulose-based hydrophobic food packaging

Global food packaging is a billion-dollar market that is projected to reach USD 464 billion by 2027. Various regulations, bans, and standards paved the way for utilizing environmentally acceptable and biodegradable materials including cellulose and its derivatives as food packaging materials. Considering end-user application requirements, a high priority has been afforded to the enhancement of the performance of nanocellulose-based sustainable materials. The swelling behavior of cellulosic materials, low resistance to wettability, and inherent sensitivity to liquid water and moisture are those characteristics of cellulosic surfaces that have made their utilization in the packaging industry more challenging. To make cellulose a more mainstream raw material for the sustainable packaging industry, surface hydrophobic modification of cellulose can be a prior choice. Hydrophobic modification strategies provide a barrier to wettability and offer low permeability to moisture for cellulose to improve the water barrier property and mechanical stability of those packaging materials that utilize cellulose as host matrix, reinforcement agent, and binder in thin films or as a coating for paper-based matrices. Moreover, superhydrophobic coatings can be applied to the inner surface of food packaging to reduce and even eliminate the adhesion of liquid foods on the inside of food packaging leading to waste reduction. This work aimed to comprehensively review the state-of-knowledge studies about hydrophobic cellulose-based packaging materials and elucidate the key indicators of each method.