ABSTRACT
[Objective] To investigate the purchase and use of edible oil , as well as recycling of kitchen waste oil in Shanghai catering service units , providing reference for relevant regulatory authorities . <br> [ Methods] A total of 976 units of various types of catering service in Shanghai were selected via strati-fied sampling methodology , a self-designed questionnaire used to investigate the purchase and use of edi-ble oil, as well as recycling of kitchen waste oil .Meanwhile, an on-site rapid detection technology was used to test items including acid value , peroxide value , polar components of unused pre -packaged edible oil and also the process of using frying oils on site . [ Results] The amount of edible oil used in catering service units of Shanghai was about 1235 tons per day;6.0% of the oil purchased was bulk cooking oil , which accounted for 5 .6%of the total amount consumed;44 .3%of the catering service units signed with professional companies for the recycling of kitchen waste oil;3615 samples were detected using an on -site rapid detection , of which 17 were suspected to be positive .The lab confirmed that test results were quali-fied. [ Conclusion] The edible oil used in Shanghai catering service units is safe in general , while bulk cooking oil may have potential safety hazards .Food practitioners have low awareness of health risk caused <br> by using edible oil repeatedly and for too long time , which makes some enterprise use “old oil” for too long;There does exist the possibility of kitchen waste oil returning to food chain as its recycling has not been standardized .