Dairy Industry: Sanitary Revolution: 1850–1917

At the same time that improvements were quickly occurring in dairy manufacturing, the fluid-milk industry was being transformed through the development of laws and processes that protected milk from contamination and consumers from disease. These changes eventually affected the entire industry. The movement began in the 1840s with an exposé on the evils of the New York swill milk industry. As objections to swill milk grew, the milk for large cities was increasingly brought in by rail, enhancing the potential for contamination. Breaking connections between producer and consumer also afforded the dealer more opportunities to adulterate the product. Farmers and dealers both attempted to sell skimmed milk (then considered almost worthless) as whole by adding chalk and other colorants. To retard souring, dealers sometimes added formaldehyde.