Processing of Cocoons

Processing of mulberry cocoons

Pre reeling process

Cocoon stifling and drying

The objective of stifling process is to kill the pupae to prevent the emergence of moths and then the cocoons are dried for preservation and storage.

Methods of stifling
Cocoon sorting

The objective of cocoon sorting is to separate the defective cocoons in lot that only good cocoons are taken for reeling. The defective cocoons like doubled, stained, flimsy etc. separated and cocoons of uniform size, shape, shell thickness are taken for reeling.

Cocoon boiling

For unwinding the filament, it is necessary to soften the gum by putting the cocoon in hot water or boiling.

Methods of boiling
Cocoon brushing

Cocoons brushing is carried out in order to find out the correct end of the filament.

Types of cocoon brushing

Reeling: Mulberry reeling is done in the following reeling devices

Charkha

This is the conventional hand operated reeling system. 50-60% of Indian raw silk production is from this reeling device. It is made of locally available material and consists of mud platform, tara patti, thread guide and reel.

Improved charkha

In this process, cooking and reeling operations are separated, Croissure pully is provided and the reel shaft and spoke are spoke are made of iron and wooden ribs and fitted are with ball bearing. Quality of yarn produced in this device is better than country charka.

Cottage basin

This is a development over the charkha hand reeling machine. The thread button and croissure mechanism is not incorporated and steam is used for production of heat and electrical motor for mechanical motors.

Multi end reeling machine

This is a modified version of cottage basin to improve to quality and production of row silk yarn. Each basin has 10-20 ends. The filaments are drawn through jetteboutte tube and the button hole. Filaments are drawn through the croissure pully and ultimately tied on the reel. The quality of raw silk in multi end machine is better.

Re reeling

Re reeling is done to make raw silk skeins of standard size and weight. Generally, the re reeling machine is constructed with iron and wooden component with "U" brackets for large reel, fitted with traversed mechanism, reel drive arrangement and silk drying facility. In Assam conventional wooden structured hand drive re-reeling machine with traversed mechanism is practised.

Mulberry weaving

Fly shuttle loom with Jacquard/dobby mechanism is used for mulberry weaving. Mulberry weaving is generally concentrated in Sualkukhi area of Assam. In Imphal, mulberry weaving is done for preparing fabric of local design. The major portion of the mulberry silk utilized in these areas comes from Karnataka and only a little locally produced mulberry raw silk is used. Generally a fly shuttle loom can consume 2.5 to 3 kg warp yarn and 5 to 6 kg weft yarn in one setting.

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