“Producer-handler” means any person that is both a producer and a handler of market milk. For the purposes of this chapter a producer-handler is a producer in any transaction which involves the sale or delivery of bulk market milk which was produced by him to a handler or to any nonprofit cooperative association of producers, and is a handler in any transaction which involves the purchase, acquisition or receipt by him of market milk, the pasteurization or packaging of market milk, or the sale or delivery of packaged market milk to any person.