write about cocoon riddling
Answers
Explanation:
Silk reeling is the process by which a number of cocoon baves are reeled together to produce a single thread. This is achieved by unwinding filaments collectively from a group of cooked cocoons at one end in a warm water bath and winding the resultant thread onto a fast moving reel.
Answer:
Cocoon quality
A series of natural circumstances will produce variations in cocoon quality. Some of the most noteworthy include:
differences in cocoon quality in the same batch;
differences in cocoons produced in the same location by different farmers who have reared the same species;
seasonal influences. In Japan for example, cocoons produced in the spring and late autumn are higher in quality than those in early autumn and summer;
environmental conditions affect cocoon reelability such as temperature and humidity;
processing technique in reeling will impact reeling efficiency as well as raw silk quality;
bivoltine cocoons are superior quality compared to multivoltine silkworm species traditional farmed in tropical zones.
Recent silkworm cultivation now develops cross-breeds of multivoltine with bivoltine silkworms as a strategy to improve overall cocoon quality.
3.2 Factors influencing cocoon quality
This section presents the measures to be taken during silkworm rearing and mounting to obtain a better quality of cocoons with higher silk content, longer filament, better reelability and lower percentage of defective cocoons.
Temperature and humidity during mounting
Maintain temperatures at or near 25ºC and relative humidity around 65 percent for silkworms to spin good quality cocoons with a high reelability.
Mounting device
Although different mount practices are employed among producer countries, rotary mounting frames provide good ventilation. The result is improved reelability of cocoons.
Harvesting and handling of fresh cocoons
Cocoons should be harvested only following complete pupation. In practice, the appropriate harvesting day would be the fifth day in tropical countries, and the seventh or eighth day in temperate countries, from the mounting date. If premature harvesting takes place, the silkworm will still be in its larval stage, weigh more, have fragile skin, and could likely be crushed, which would cause stains to the cocoon during handling and transportation.
Transport of fresh cocoons
After proper harvesting and removal of diseased or damaged cocoons, the fresh cocoons are taken to the market. For short distances, the farmer carries the cocoons in bamboo baskets or jut bags on his head or by bicycle. If the distance is longer, cocoons are transported in a van or a bus. Caution should be exercised when loading fresh cocoons on to the van to ensure that containers are loosely packed in tiers to avoid damage. Vibration and shock during long trips can spoil fresh cocoons. Cocoon quality is affected by steam produced while being transferred in a bag or basket. If there are defective cocoons (see section 3.3) fresh cocoon quality will be harmed.
Table 9 describes the impact of transportation on fresh cocoons. While it is advisable to avoid carrying cocoons over long distances, there are steps, which preserve silk reelability. First use of P.V.C. containers with 15 kgs capacity is recommended. Shock absorbers, such as sponge can prevent damage over long distances. To minimize the risk of heat deterioration, shipping should take place only during the night or early morning. Ideally, the fresh cocoons should arrive at the stifling unit within two to three days after harvest.