Reinforcement of Yeast Biomass Films with Bacterial Cellulose and Rice Husk Cellulose Nanofibres

In the last decades, cellulose nanoparticles have been widely used to reinforce polymeric materials due to their strength and their wide availability in nature. Cellulose nanoparticles are entirely compatible to reinforce natural polymers, as performed in this study. The effect of rice husk cellulose nanofibers (RHCNF) and bacterial nanocellulose (BNC) on water vapor transfer and mechanical properties was studied in yeast biomass films, made from dispersions at pH 6 and 11. Water vapor permeability was reduced at 5 wt% in both reinforcements in films prepared at pH 11, although their influence was negligible at pH 6. Despite both cellulose nanofibres have similar aspect ratios, Young’s modulus, tensile strength, elongation and tensile toughness of films reinforced with BNC were significantly increased with respect to RHCNF films, and both were better than the pure matrix. In this way, the present study provides an interesting contribution regarding the effect of the mentioned nanocellulosic reinforcements on yeast biomass films used for packaging purposes. Graphic Abstract