6.
A microbial process that partially degrades
tissues and separates fibers from non-fiber
material
The degradation of pectin, which is a
compound that binds cells and tissues
together in plants, is key to the retting of
flax.
Retting
7.
Scanning electron
micrographs of flax stems
Left: unretted cross
section of stem showing
bast fibers in bundles
between the cuticle and
woody core
Right: dew-retted cross
section of stem showing
separation of fibers and
fiber bundles from the
non-fiber tissues
Retting
8.
9.
By spraying some 4o salts, e.g. Glyphosate, N-
phosphono-methylglycine, a broad-spectrum
systemic herbicide used to kill weeds
It is typically sprayed and absorbed through the
leaves.
At the mid point of flowering cause uniform pre-
maturation of the standing plant
The stems are retted in situ
I. Stand Retting
15.
Cold Water Retting Warm Water Retting
2-3 weeks or longer More quickly
Vast space Less retting space
Rivers, ponds…. Equipped retry
Low cost High cost
Anaerobic Water Retting
18.
Anaerobic water liquor Aerobic liquor
Low pH High pH
↑Offensive smell ↓Offensive smell
↑Volatile acids ↓Volatile acids
↑OD ↓OD
↑ Waste accumulation Not the same waste
accumulation
Low potential of reuse Used over and over again
Anaerobic vs. Aerobic
19.
The Main Retting Techniques ( cont.)
I. Stand retting
II. Water retting
III. Enzyme retting
Scutching (the 5th step)
Contents