Article 35 of the Food Safety Law stipulates that: the state implements a licensing system for food production and operation. Engaged in food production, food sales, catering services, shall obtain a license according to law.

As a middle school canteen, as long as the food business license is obtained, the purchase channel is formal and transparent. If the finished food is accepted, the food delivery enterprise should also obtain a valid food business license. So as long as the documents are complete, legal and effective, and the food raw materials are qualified, they can be purchased and used. There is no provision in the Food Safety Law that "finished products and semi-finished products cannot enter the canteen".