Producing nanofibres from carrots with a chemical-free process

The production of nanofibres (NF) from fresh carrots residue was investigated with a mechanical process without using any pulping or bleaching chemicals. Refining with a PFI mill followed by mechanical fibrillation with a homogenizer was used to produce fine NF. Blanching with hot water was carried out to leach the extractives from carrot fibres prior to refining. The energy required to prepare carrot pulp is one order of magnitude lower than for wood pulp and the fibrillation of nanofibres from carrot residue is four times lower in energy than using wood pulp as feedstock. The average diameter and length of carrot NF are 18 nm and 5.1 μm, respectively. The chemical composition of the manufactured nanofibers, as measured by HPLC, was 53% glucose and 47% xylose. Translucent and strong flexible films were prepared from the carrot NF using a filtration based papermaking process. The strength and water vapor permeability of these carrot NF paper like composites are similar to those derived from wood-fibre of comparable dimensions.