Dairy

What is a Dairy and Its Historical Significance?

A dairy is more than just a place where milk is stored; it’s the heart of an industry that has been central to human nutrition for millennia. Historically, milking was done by dairymaids, with the term ‘dairy’ coming from Old English, signifying female servants. But as we delve into the modern dairy industry, we find a complex web of processes and technologies that have transformed how milk is produced and consumed.

The Evolution of Dairy Production

From cottage industries to large-scale commercial operations, the structure of the dairy industry has evolved significantly. In the early days, people would milk animals by hand or use simple machines designed for this purpose. Hand-milking involves grasping the teat and squeezing it in a specific manner to close off the milk duct, then expressing the trapped milk into a bucket. This method was labor-intensive but effective.

As farms grew larger, milking became more mechanized. In 1907, milking machines were introduced with a claw, teatcups, pulsator, and vacuum system for efficient milk harvesting. These machines not only increased productivity but also kept the milk enclosed and safe from external contamination.

The Structure of Dairy Plants

Dairy plants process raw milk by heat treatment and dehydration to extend its marketable life. Cream and butter are processed into various consumer products, including powdered milk, condensed milk, and home-consumption sized packs of butter. Skimmed milk is the product left after cream removal. To make consumable liquid, skim milk is mixed with a portion of cream to create low-fat or whole milk, which may have additives such as calcium, vitamin D, and flavoring.

Casein found in fresh milk has various uses including food and industrial applications. Cheese is made from whole milk by forming curds, which can be processed into different types depending on the country’s regulations. Whey is a byproduct of cheese making and can be used to make lactose-free products. Yogurt making involves stopping the cheese-making process before curdling hardness.

Modern Milking Systems

The introduction of milking machines in 1907 marked a significant shift in dairy production. These machines work by creating pressure differences across the teat canal to massage milk from the cow’s udder, then transporting it through a hose and storing it in refrigerated bulk tanks or central storage vats.

Herringbone milking parlours have cows enter single file and line up almost perpendicular to the central aisle of the milking parlour on both sides of a central pit. Swingover systems operate with one set of milking cups shared between two rows of cows, while rotary systems can handle over a thousand cows.

Automatic milking sheds use robot arms to clean teats and apply equipment. Computer-controlled gates direct cow traffic, allowing farmers to ration supplements and monitor cow activity. In the dairy industries, two main types of wastewater are produced: dairy wastewater and cheese whey. Proper sanitation practices and pasteurisation reduce the risk of bacterial contamination in dairy products.

Health Risks and Environmental Concerns

Dairy production can pose health risks to humans, such as leptospirosis, cowpox, tuberculosis, brucellosis, listeria, and Crohn’s disease caused by M. paratuberculosis. The dairy industry also raises concerns about animal welfare and environmental impact.

The corporate dairy industry, the government, and schools form a troika of immense influence that hides from public view the animal rights violations and cruelties happening within the dairy industry. In 1937, bovine somatotropin (BST or bovine growth hormone) was found to increase milk yield. Several pharmaceutical companies developed commercial rBST products, which have been approved for use in several countries but are banned or restricted due to negative animal welfare effects.

In conclusion, the dairy industry has come a long way from its humble beginnings. From hand-milking to automated systems, it continues to evolve with new technologies and practices. As we navigate this complex landscape, it’s important to consider both the benefits and challenges of dairy production.