In order to obtain the optimal pre- cooking conditions and parameters of Apostichopus japonicus,its quality changes were studied in the process of boiling with distilled water( I) or saline solution with different concentration( 1%,3%,6%)( Ⅱ,Ⅲ,Ⅳ) and steaming with no water( Ⅴ) or water( Ⅵ).The results were as follows:mcrobial residues and crude protease activity declined with time. The sequence of the ability of lowering bacteria and protease activity was( Ⅰ,Ⅱ,Ⅲ and Ⅳ),Ⅴ,Ⅵ,but there were no significant diff...