Influence of cooking and adjustment treatments on reeling and quality characteristics of raw silk

The hot air dried Indian multi-bivoltine cocoons (PM x NB4D2 race) treated at different cooking temperatures, cooking durations and adjustment temperature profiles in pan system of cooking have been found to have significant influence on reeling characteristics, viz. groping end efficiency, reelability, raw silk percentage, raw silk recovery percentage, reeling tension, waste generated during reeling, pelade weight generated and degumming loss percentage of silk waste, and on quality characteristics, viz. neatness, cleanness, cohesion and degumming loss percentage of raw silk. However, the complete cooking and reeling do not show significant influence on sericin dissolution during cooking and reeling, tenacity and elongation. The study clearly shows that the complete cooking of cocoons in pan system of cooking using five treatment temperatures effectively softens the sericin uniformly in different layers of the cocoon shell compared to single temperature treatment, thus facilitating the improved reeling performance from hot air dried Indian multi-bivoltine cocoons. The cocoon cooked using the retting temperature of 50degreesC for 1 min, high permeation temperature of 90degreesC for 2 min, low permeation temperature of 60degreesC for 1 min followed by the cooking temperature of 93-95'C for 2 min and adjustment temperature of up to 60degreesC yields better reeling performance and quality of raw silk.