Starch-Hibiscus-Cellulose Nanofibrils Composite Films as a Model Antimicrobial Food Packaging Material

The large amounts of coffee husks (CHs) waste matter generated from coffee farms and factories has been considered as a new non-wood source of cellulose. The aim of this work was to fabricate an edible food packaging material from starch incorporating TEMPO-oxidized cellulose nano-fibrils (TOCNFs) and hibiscus extracts to boost its mechanical and antibacterial properties respectively. In this study, three schemes were employed to fabricate this enhanced novel nanocomposite film of starch, hibiscus and TOCNF Firstly, glycerol was used as the plasticizer on the formation of the starch film to give mobility to the α-D-glucose structural chains making the composite film more flexible. Secondly, TEMPO-oxidized cellulose nano-fibers derived from coffee husks were thrown into the mix to enhance the mechanical properties of the starch matrix and to control water vapor permeability and solubility. Lastly, the antimicrobial activity and UV resistance of the films were enhanced through incorporation of hibiscus crude extracts which were infused into the nanocomposite films.