Acetobacter sp. growing medium was modified in order to produce bacterial cellulose (BC) nanocomposites using a bottom-up technique that allowed starch to be introduced into the cellulose network. The BC-starch mats were hot-pressed to obtain nanocomposites sheets. Morphological characterisation was carried out using Atomic Force Microscopy and Environmental Scanning Electron Microscopy. The images obtained from microscopy were then processed using image analysis. Network properties, such as mesh size and fibre orientation were characterised. Fracture surfaces of these new nanocomposites were analysed. ©Smithers Rapra Technology, 2008.