Mich. Comp. Laws § 289.2131

Sec. 2131. (1) When the department determines such action will promote honesty and fair dealing in the interest of consumers, the department shall promulgate rules fixing and establishing for any food or class of food a reasonable definition, standard of identity, and reasonable standard of quality and fill of container. (2) In prescribing a definition and standard of identity for any food or class of food in which optional ingredients are permitted, the department shall designate the optional ingredients that are required to be named on the label.