Mich. Comp. Laws § 750.468
Shipment of baked goods and pastries in sanitary and dust proof containers-It shall be unlawful for any person engaged in the manufacture of baked goods and pastries, by himself or his agent or employe to convey, ship or transport any baked goods or pastries from the place where such goods are manufactured to any place in this state where such baked goods and pastries are to be consumed or offered for sale, without first placing such baked goods and pastries in a clean and sanitary container or package sufficiently tight and compact to exclude all dust and dirt and other contamination. None of such containers or packages containing baked goods or pastries shall be opened or exposed to the dust or dirt or other contamination from the place where manufactured until they arrive in the place where such baked goods and pastries are to be consumed or exposed for sale.
Any person who shall violate any of the provisions of this section shall be guilty of a misdemeanor.
MCL 750.468