Cellulose nanocrystals as reinforcements for collagen-based casings with low gas transmission

Cellulose nanocrystals (CNCs) of excellent mechanical properties, high purity, high aspect ratio, and cost-efficient production have drawn many attentions as a new class of reinforcement nanofillers. We chose CNCs as reinforcement nanofillers, which were incorporated in collagen to prepare CNCs/collagen casings by a traditional extruding method. The effects of CNCs on these casings were investigated. The dispersity and compatibility of CNCs within the collagen are rather good. The presence of CNCs can improve the light transmittance, barrier property, tensile strength, Young's modulus, and thermostability of the CNCs/collagen casings, where collagen might cross-link with CNCs by electrostatic and hydrogen bonding interaction. When the CNCs content is 4 wt%, the water vapor permeability of CNCs/collagen casing reaches the minimum of 0.18 g.mm/h.m(2).KPa. That concentration gave the highest light transmittance, and the mechanical properties were optimal. The development of CNCs/collagen casings represents an important potential to extend shelf life by the prevention of lipid oxidation and water loss of sausages.