In all prosecutions arising under the food and drug laws of this state for the manufacture or sale of an adulterated, misbranded, or otherwise unlawful article of food, drink, condiment, or drug, the standards of purity for food products, established by the United States secretaries of agriculture and health and human services, in effect on the date this 1986 amendatory act takes effect, shall be accepted as the legal standards, except in cases where other standards are specifically prescribed by the laws of this state.