Studies on Pan Cooking of Indian Bivoltine Cocoons
In India, most of the cocoons are cooked using an open pan cooking device and the cooking method is mainly applied for float reeling. Three-pan cooking method for half-sunk reeling and automatic cooking method for sunk reeling have already been introduced but these methods are not being applied widely. In order to obtain high quality raw silk from bivoltine hybrid cocoons, it is necessary to develop a simple cocoon cooking method for sunk reeling. An attempt was made in this study to develop a cocoon cooking method using 2 pans for sunk reeling. The samples consisted of KS×NB4D2 bivoltine hybrid cocoons. First, the temperature distribution inside the cocoon cooking pan was determined by using a thermometer. It was shown that the highest temperature that could be used was 96℃ for this pan cooking device and it was also observed that there was a 3 or 4℃ difference in the vertical distribution of the water temperature between the top and bottom portions of the pan. Second, the cocoons cooked after changes in the temperature and time were reeled. Based on the values of brushing waste weight, thickness of the dropped cocoons and number of reeled cocoons, the cocoon cooking degree was evaluated. Then, the 2-pan cocoon cooking method was proposed. Third, the 2-pan cocoon cooking method was compared to the 3-pan and the automatic cocoon cooking methods based on reeling results. When the 2-pan cooking method was used, reelability and nonbreakable filament length were superior to those of the other two methods. On the other hand, brushing waste weight was larger and raw silk percentage was lower than those of the other two methods. Although the 2-pan cocoon cooking method may lead to over-cooking, it could be used for simple sunk reeling.
|作成者||Kozo TSUBOUCHI Subhas Venkappa NAIK T.H. SOMASHEKAR|