It is hereby declared that fluid milk and fluid cream are necessary articles of food for human consumption; that the production and maintenance of an adequate supply of healthful milk of proper chemical and physical content, free from contamination, is vital to public health and welfare, and that the production, transportation, processing, storage, distribution and sale of fluid milk and fluid cream in the State of California is an industry, in whole and in part, affecting public health and welfare; that unfair, unjust, destructive and demoralizing trade practices have appeared within this industry and these practices constitute a menace to the health and welfare of the inhabitants of this state by threatening the stability of this industry and by thereby endangering the assurance to the people of the State of California of the maintenance of an adequate supply of this necessary commodity; that it is a policy of this state to promote, foster and encourage the intelligent production and orderly marketing of commodities necessary to its citizens, including fluid milk and fluid cream, and to eliminate speculation, waste, improper marketing, unfair and destructive trade practices, and improper accounting for milk purchased from producers.