“Canned Milk” shall be received from sources and handled in a manner acceptable to the secretary with respect to sanitation and protection of public health. There shall be a presumption that such milk is so received and handled but the secretary, in his discretion, may check and verify this and come to his own determination. If “canned milk” in its final container is found to be unsafe or contaminated, the secretary shall have the right to exclude it from sale in Pennsylvania.