Chitosan-nanocellulose biocomposites were prepared from chitosan having molecular weight of 600-800 kDa, nanocellulose with 20-50 nm diameters and various levels of 30, 60 and 90% (v/wCHT) for glycerol. Agitation and sonication were used to facilitate even dispersion of particles in the polymer matrix. The nanocomposites were examined by differential scanning calorimetry, X-ray diffraction and agar disc diffusion tests; finally, the film was applied on the surface of ground meat to evaluate its performance in real terms. Chitosan-nanocellulose nanocomposites showed high Tg range of 115-124°C and were able to keep their solid state until the temperature (Tm) range of 97-99°C. XRD photographs revealed that nanocellulose peak completely disappeared after their addition to chitosan context. Agar disc diffusion method proved that the nancomposite had inhibitory effects against both gram-positive (S. aureus) and gram-negative (E. coli and S. enteritidis) bacteria through its contact area. Application of chitosan-nanocellulose nanocomposite on the ground meat decreased lactic acid bacteria population compared with nylon packaged samples up to 1.3 and 3.1 logarithmic cycles at 3 and 25°C after 6 days of storage, respectively.
Keywords: Carbohydrate polymers; Chitosan; DSC; Ground meat; Nanocellulose; XRD.
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