Any person who shall willfully hinder or obstruct the dairy and food commissioner, or his deputy, or other person or inspector by him duly authorized, in the exercise of the powers conferred upon him by this act, shall be deemed guilty of a misdemeanor, and on conviction shall be punished by a fine of not less than 10 dollars nor more than 100 dollars, or by imprisonment in the county jail for not less than 10 days nor more than 90 days, or both such fine and imprisonment in the discretion of the court.