The provisions of this act shall not be deemed to in any manner restrict the authority of the Department of Health and Environmental Control to regulate or ban the use or consumption of distressed food donated, collected or received for charitable purposes but deemed unfit for human consumption, nor shall the exemption from liability provided for in this chapter in any manner affect the liability of a producer or processor of food products for defects existing in a food product prior to the time such product became "distressed food" as defined in § 15-74-10.