Spray Enzymatic Retting: A New Method for Processing Flax Fibers

The high consumption of flax for linen in the U.S. and the fact that the U.S. does not produce any flax or linen has prompted research into the ultimate goal of re-establishing a flax/linen industry. An improved retting method for flax stems using pectinase-rich mixtures is developed and evaluated on a variety of fiber and seed flax samples. The method, termed spray enzyme retting (SER), is as follows: crimp stems to enhance penetration of enzyme formulations into the stems tissues, add chelators with enzymes in water at pH 5.0 to improve enzyme effectiveness, spray the formulation on crimped stems to soaking, and incubate at high humidity for several hours. Total fiber yield, collected from dried and bench carded SER flax, and fiber strength and micronaire (modified to use 5 g of fiber) are determined and compared for various sample types, forms, and amounts. A test of 19 samples indicates that the liquid : fiber ratio (in ml/g), after subtracting excess run-off of enzyme formulation, is 1.86 ± 0.5. Total fiber yields are about 25 to 30% of starting crimped weight of fiber flax stems and considerably higher for samples previously dew retted prior to SER. Micronaire values are high (about 7-8) for bench carded samples and lower (about 4 to 5) for the finer proportion from samples cleaned through a Shirley analyzer. Depending on the samples, fiber strengths (Stelometer) are equal to or consid erably greater than dew retted "cottonized" flax or typical cotton fibers.