Chemical Degradation
Measurement of the non-cellulosic binder breakdown in harvested flax stalks determines the optimal harvest window. This degradation, evaluated as the retting degree pectin matrix, indicates the portion of pectin that has been removed by fungi or chemical treatment. Flax fibers are bound together and to the stem by this matrix, which must be partially destroyed to allow fiber separation.
Determining this degree prevents the damage that occurs when too much or too little pectin is removed.
Extraction Efficiency
Mechanical separation of flax fibers from the woody core, known as scutching, is more efficient when the binder is correctly degraded. A high retting degree pectin matrix value means that the fibers separate easily without breaking, yielding a high proportion of long line fibers. Conversely, an insufficient retting degree leaves the bundles stuck to the wood, which increases the amount of short, low-value tow produced during scutching.
Spinners require a precise retting level to ensure that the fibers can be drawn into a uniform yarn on the drafting frame.
Fiber Integrity
Over-retting occurs when the fungal decay begins to attack the cellulose in the fiber walls. This attack weakens the technical fiber bundles and lowers yarn strength. Monitoring the pectin breakdown prevents this degradation.
