Retting flax stalks

The USD A Flax Pilot Plant (Flax-PP) contains a separate research component for enzyme-retting plant stalks to engineer fibers with desired properties, to optimize enzyme-retting, and to enhance processing. Pilot scale tests of commercially cleaned flax indicated that fiber strength, fineness, and yield could be varied by enzyme/chelator levels (Akin et al. 2001). Our proposed current method to enzymatically ret flax stalks includes commercial pectate lyases after chelator for high... 

Hemp is retted in water tanks in a manner similar to flax, after which the stalks are laid out to dry. The fibres are then separated either manually or mechanically by passing through fluted rollers which crush the woody tissues. At this state the hemp is softened by beating with a softwood mallet on a flat stone or a hard floor. The same effect can also be achieved when a heavy millstone, usually operated by water power, rolls over the fibres for 3 or 4 hours. Finally the fibres, which tend to stick together, are separated by combing. 

To facilitate and integrate research on bast fiber retting and subsequent processing, a pilot plant was established to quickly and effectively evaluate processes (Akin et al. 2005 Foulk et al. 2008a, 2009). The USDA Flax Fiber Pilot Plant (Flax-PP), the only research facility of this type in the US, is able to process and extract bast fibers from retted and unretted plant stalks using commercial-type equipment. 

Bacci et al. [39] treated nettle stalks with boiling soda solution xmtil the bark, the source of fiber, was easily removed from the core of the stalk than performed alkalization treatment on the bark. Enzymatical fiber retting maybe faster and more reproducible than the traditional biological fiber retting methods and is extensively studied for flax and hemp extraction enhancement [39]. 

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