The Microbiology of Raw Milk

Milk and dairy products are consumed worldwide and considered as relevant sources of nutrition in humans and animals, not only the newborns. Due to the complexity of the dairy chain, microbial contamination can occur in different steps of production, leading to the development of adequate control plans for monitoring the microbial quality and safety of milk since production to processing. Different microbial groups can contaminate milk, with a wide range of impacts for its quality, safety, and even beneficial features. Important microbial groups are researched in milk to assess the hygienic procedures and conditions during production, such as mesophilic aerobes and coliforms; some groups are considered as relevant spoilage agents, such as psychrotrophics; many bacteria are researched due to their pathogenic potential, such as Listeria monocytogenes and Salmonella spp.; and other bacteria can possess beneficial features, like some lactic acid bacteria strains. This huge diversity is a challenge in the dairy industry, once their monitoring and control became mandatory to testify and guide the raw milk utilization by consumers and dairy industry.