Assessment of enzyme treated wool samples
The BIOFELT project carried out a technical assessment on enzyme treated wool samples and fibres. The samples' morphology was studied using a scanning electron microscope. The differences between stages in fabrication and different treatments were recorded. A reference standard cloth was compared with samples that had undergone an alkali solubility test. Single steps in fabrication were investigated using piano hammers to study tension release. The amino acid pattern of samples were examined and compared with a reference value. Vegetable contaminants of wool, ring burrs and grass seeds, were treated with commercial cellulase, xylanases and pectinase, both separately and in combination. Measuring reducing sugars and soluble carbohydrate content of the treatment solution gave an indication of the breakdown of vegetable material. The effects of different enzymes on the weight loss of different grass seeds were also noted. Also studied were the individual and combined effects of peroxidase and laccase on ring burrs and the possible removal of lignin. Felted yarn and prefelted samples of material treated with protease showed an improved uptake of colour compared to untreated samples. Samples treated with protease showed deeper colouration when subjected to different dyes. Laboratory scale experiments indicated that low-temperature dyeing at 60 degrees Celsius resulted in uneven colouration. Prefelted material treated with protease and dyed at 90 degrees Celsius gave a similar or marginally improved result to untreated reference material dyed at 98 degrees Celsius. However, when the process using protease was carried out on a pilot scale with felted examples severe fibre damage was observed. The project's findings will help reduce manufacturing costs of felt and carbonising wool due to savings in energy, water and time. The competitiveness of the European felt industry will also be enhanced through updated production methods and a higher market profile for wool felts.
