After harvest, flax stalks are allowed to dry in open air for several weeks before they undergo threshing , or removal of seeds from the stalk by crushing open the dried seed pods. Hand threshing is usually achieved by simply beating the dried stalks until all the seed pods have been crushed, then shaking the seeds free.
Flax fibers are considered bast fibers. Bast fibers are fibers collected from the phloem , or the inner-bark of the plant. Fabrics made from these fibers are typically quite strong and durable fabrics. Aside from linen, a few other fabrics made from bast fibers include hemp, ramie, and rattan. You may remember from your Biology class that the phloem is one of the two vascular structures inside of plants that carry nutrients throughout the organism the other is the xylem , or the woody core.
These fiber nodes are also what make linen fabric flexible without being brittle. This is achieved via a process called retting --or, literally, rotting. And yes, with the same awful smell! The malodorous process of retting can be achieved in a variety of ways, but it typically involves prolonged exposure of the stalk to moisture.
Plants hold themselves upright by increasing water uptake into their cells, which causes the plasma membrane to swell and increases internal pressure against the cell wall. This pressure keeps the plant structures stiff Biology review: Turgor pressure. Prolonged water exposure during retting eventually causes the cells of the phloem to lyse , or burst open, and allows local micro-organisms that break down the sticky pectins to invade the plant cell.
The image to the right is a c ross section of a bast fiber: "X" is xylem; "P" is phloem; "C" is cortex; "BF" is bast fibers. How do these micro-organisms break down those sticky pectins? A man named Sergei Winogradsky figured out the answer to this question back in the s.
Winogradsky, a microbiologist and soil ecologist, is actually quite famous for this answer - his discovery of chemosynthesis - a process wherein autotrophs organisms that make their own food absorb carbon and inorganic nutrients from their surrounding environments in order to mediate the chemical reactions with which they create their own energy. Prior to this discovery, scientists believed that all autotrophs were dependent upon sunlight for energy production remember photosynthesis?
But Winogradsky found a little bacterium living in the root nodules of legume plants that changed everything. He identified it as Clostridium Pasteuranium , an obligate anaerobe that, by definition, cannot survive in the presence of atmospheric oxygen O 2. The presence of this autotrophic bacterium inside of the root nodules, without access to atmospheric oxygen and therefore also without access to sunlight, led Winogradsky to investigate how it managed to survive.
He found that C. Pasteuranium uses water molecules to break up the sticky pectin bonds that hold the bast fibers to the phloem, a process called hydrolysis. It then uses the chemical pieces of the broken up pectins to create ammonia NH 3 out of free, bioavailable nitrogen N 2 in its surrounding environment, which can then be utilized by the bacteria in its metabolic processes.
This is is called nitrogen fixation. Scientists have since isolated more than 22 different kinds of autotrophic, pectin-dissolving bacteria from retted flax, mostly belonging to the Clostridium family. Dew retting is the preferred method in areas where water sources are limited but that enjoy warm daytime temperatures and heavy nighttime dews. Flax stalks are spread out evenly across a grassy field, where the combination of air, sun and dew causes fermentation, which dissolves much of the stem within weeks.
Dew-retted fibers are typically of poorer quality and more darkly pigmented than natural water-retted fibers. Tank retting takes place in large vats that are typically made of cement, as the acidic waste products of the bacteria corrodes metal. Stalks are first leached, or soaked, for hours to removedirt and pigment from the bundles. Linen is made following a series of steps that have been perfected over several generations, creating what is considered today as one of the most sustainable textiles.
Step 1: Flax is planted in a cool climate and after approximately days is harvested. Step 2: The fibers are separated. The leaves and seeds of the plant are removed, as well as the flax fibers located inside the dried stems.
In the past, this occurred using a long wooden blade. Today, advanced technology crushes the stalk using metal rollers. Step 4: The fibers are removed, and other parts of the plant are set aside for other purposes such as making paper, which enhances the sustainability of the process.
This leaves behind the long flax fibers. Step 6: The fibers are then spun into yarn before they are woven into a textile product. Because of the method that flax fibers are grown and the method that linen is made; this textile is extremely sustainable compared to other textiles such as synthetics. Linen is biodegradable as well.
Overall, however, linen is one of the least environmentally damaging textiles. Unlike synthetic textiles, natural fabrics like linen are biodegradable, which means that their constituent molecules reabsorb into the surrounding environment within a matter of years instead of centuries. If linen is cultivated in accordance with proper stewardship of the land, it is not environmentally harmful. To meet the global demand for linen products without incurring prohibitive overhead costs, however, the majority of linen producers choose to use inexpensive processes that may be environmentally damaging.
A variety of linen fabric certifications are available to ensure that linen fibers are produced with sustainable and responsible means. This non-governmental organization NGO focuses specifically on textile products, which means it imposes stricter organic standards that focus specifically on the particulars of textile production.
About the author:. Sewport Support Team is the founder and CEO of Sewport - an online marketplace connecting brands and manufacturers, former founder of various clothing manufacturing services.
He is passionate about e-commerce, marketing and production digitisation. Connect with Boris on LinkedIn. Did you know we helped over brands find garment manufacturers and specialists and we can help you too Table of contents What Is Linen Fabric? Planting 2. Growth 3. Harvesting 4. Fiber Separation 5. Breaking 6. Combing 7. Spinning 8. Reeling 9. Where Is Linen Fabric Produced? Damask linen 2. Plain-woven linen 3. The Hugenots eventually brought linen manufacturing over to England and Northern Ireland — and since then, linen has been made all over the world.
Just like cotton fabric, linen is made from a natural source — a plant. Linen is created from the fibres that naturally grow as part of the flax plant, a plat that grows all over the world. The production process is quite simple, which is why linen has been used for so long, but more modern techniques have been adopted in many places.
The fibres first have to be naturally degraded from the plant. This is achieved through "retting". This is a process which uses bacteria to decompose the pectin that binds the fibres together.
Natural retting usually takes place in tanks and pools, or directly in the fields. There are also chemical retting methods; these are faster, but are typically more harmful to the environment and to the fibres themselves. After retting, the stalks are ready for "scutching".
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