How Silk Is Extracted from Silkworm Cocoons, Plus Types, Prices, and How to Tell Real from Fake
Silk is a continuous long fiber formed when the silk liquid secreted by a mature silkworm solidifies as it spins its cocoon. It is also called natural silk and is a natural fiber.So how is silk extracted from silkworm cocoons? How many types are there? Roughly how much does it cost per jin? How can you tell real from fake?According to the Changsha Gaoqiao wholesale market, six jin of fresh cocoons are needed to extract one jin of silk, and silk is priced at 180-220 yuan, so the formula for calculating the price of dried mulberry silkworm cocoon silk is dried cocoon silk price * weight plus cost.
How is silk extracted from silkworm cocoons?
1. The live silkworm pupae and parasitic fly eggs inside fresh cocoons will, after a certain period, turn into moths or emerge as maggots and bore out through the cocoon shell, damaging the cocoon layer and making reeling impossible. Therefore, the pupae and maggots must be killed promptly using hot air or electromagnetic waves and an appropriate amount of moisture removed so the cocoons dry out, do not rot or deteriorate, and are easy to store.
2. The drying process of silkworm cocoons is also called cocoon baking. Dried silkworm cocoons are called dried cocoons. To prevent dried cocoons from becoming moldy and deteriorating, temperature and humidity control must be strengthened during storage, along with insect-proof and rat-proof measures. Mulberry silkworm cocoons are generally reeled from dried cocoons.
3. The dissociation of silk from fresh tussah silkworm cocoons is better than from semi-dried and dried cocoons, so in northern China fresh cocoons are used for reeling in both winter and spring. After April, that is, before the pupae become moths, the pupae-killed dried cocoons are put into cocoon cages and kept outdoors, or dried and then stored in warehouses. Because temperatures in southern China are higher, fresh cocoons are not suitable for reeling and, like mulberry silkworm cocoons, are dried before storage.
How many types of silk are there?
1. Silk is a continuous long fiber formed when the silk liquid secreted by a mature silkworm solidifies as it spins its cocoon. It is also called “natural silk.” Like wool, it is one of the animal fibers humans have used for the longest time.
2. Depending on the food they eat, silkworms are further divided into mulberry silkworms, tussah silkworms, cassava silkworms, camphor silkworms, willow silkworms, and Chinese oak silkworms, among others. The silk filament drawn from a single cocoon is called a bave; it is formed from two single fibers bonded and covered by sericin.
3. The silk strand formed by drawing out the silk filaments of several cocoons and bonding and wrapping them with sericin is divided into mulberry silk (also called raw silk) and tussah silk, collectively known as silk. Silk with the sericin removed is called degummed silk.
How can you tell real silk from fake?
1. Pull the silk a bit: silk is relatively fine and even, and it is very tough, so it does not break easily. Silk fibers have a certain ability to stick to one another.
2. Silk is a natural fiber. When held to a flame, it goes out as soon as the flame source is removed and does not produce an open flame.
3. When silk burns, it does not produce an open flame, and the smoke it gives off is white. Silk turns to char when burned and feels like a powdery substance to the touch.
4. After a silkworm becomes a cocoon, if you put it to your nose, it has a faint fragrance, but once made into a finished product it will have no smell at all. Even so, you can still identify real silk by smell. When silk burns, it gives off an odor similar to burning hair, because the main component of silk is protein.
5. Silk is very expensive. The current purchase price of silkworm cocoons is 40 to 50 per kilogram, and finished silk products are more than 150 yuan. Add processing fees and taxes and the like. Products with low prices are unlikely to really be silk.