Submitted to: Journal of Natural Fibres
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/20/2003
Publication Date: 11/20/2004
Citation: Akin, D.E., Henriksson, G., Evans, J.D., Adamsen, A., Foulk, J.A., Dodd, R.B. 2004. Progress in Enzyme-Retting of Flax. Journal of Natural Fibres. Vol. 1, pp. 21-47.
Interpretive Summary: The development of a flax fiber industry in the US is impaired by lack of a retting method that provides consistent quality fibers. Research has been conducted over a series of years, with involvement of several research associates and collaborations with universities, to undertake a comprehensive evaluation of enzyme-retting. Results indicate that two commercial products, one a pectinase-rich enzyme mixture and the other a chelator, constitute a successful retting formulation to produce consistent quality flax fibers from various sources. This research has the potential to replace the current retting method and provide a basis for better quality, domestic source of flax fibers for the US.
Technical Abstract: New methods for retting flax are sought to overcome problems in the current method of dew-retting of flax. Published data are reviewed and new data presented on the development and testing of a method to ret flax using pectinase-rich enzyme mixtures plus chelators based on cost and fiber yield and properties. In spray enzyme retting (SER), flax stems are crimped to physically disrupt the plant's protective barrier and then sprayed until soaked with, or briefly immersed in, an enzyme/chelator formulation. Flax is then incubated at temperatures optimal for enzyme activity, washed, and dried. Pilot scale tests, conducted with 10 kg samples of flax retted with a series of formulations, showed that this method effectively retted flax stems from a variety of sources, including fiber flax, mature fiber flax, and linseed straw. Fiber yield, strength, and fineness were significantly influenced by variations in enzyme-chelator amounts. Cellulases in pectinase mixtures appeared to preferentially attack dislocations in fibers and fiber bundles resulting in loss of fiber strength. Polygalacturonases alone effectively separated fiber from non-fiber components. The SER method proved to be an effective framework for further tests on enzyme-chelator formulations that now must be integrated with physical processing to optimize the extraction of flax fibers based on cost and fiber yield and properties.