Background Agricultural Connections
Dairy farmers in the United States provide milk, cheese, and yogurt from approximately 51,000 farms, 97% of which are family-owned. The average herd size in the U.S. consists of 115 dairy cows and each cow can produce 6-7 gallons of milk per day. Dairy cows are strictly female cows raised by a farmer for milk production. California is known as the highest milk-producing state as it yields 21% of our nation's milk production. For this lesson student's experiences for drinking milk and eating dairy products such as yogurt, cheese, or ice cream would be required for helping them gain an understanding for the use of tools and technology on a dairy farm.
Through time, many tools and technologies have been developed to improve the quality, processing, and safe storage of milk and other dairy products. The following tools were used in earlier times before transportation provided refrigeration and adequate storage.
- A milk tester was used to test the fat content of milk and cream. It was produced by Dr. S.M. Babcock in 1890. These small hand- cranked devices were commonly found on dairy farms. Farmers used it to compare the butter fat content of milk from each cow.
- A cream separator was invented in 1890 by C.G.P. Delavai and was used to separate cream from the milk. This machine eliminated this task by hand for transporting whole milk to the creamery.
- A butter paddle was used after the cream was churned and the butter was put in a large bowl. This tool was used to separate the butter from the buttermilk and to form butter into a solid form.
- The self-acting cheese press performs one step in the cheese making process by pressuring the cheese curds and helping drain the access liquid. This press used the weight of the cheese to extract the moisture out of it. This type of cheese press was commonly used in smaller dairies.
- The foot operated butter churn was hands-free and allowed you to do something else! Butter churns separated the butter milk and butter. The primary purpose of having dairy cows was to provide a family with milk and butter. Farm production of butter started in 1791.
- The 8 gallon milk can was used to store and transport cooled milk. Until the adoption of farm bulk tanks and tanker trucks in the 1940s and 50s, milk was kept in these cans which came in 5, 8, and 10 gallon sizes. Sturges & Burn Manufacturing Company of Chicago, Illinois was a large manufacturer of milk cans.
- The earliest milk haulers used flat-bed delivery trucks to transport milk cans of various sizes along with other items such as eggs and ice.
- Milk was delivered to houses by a milk man in glass milk bottles that were thought to keep milk at its coolest temperatures.
Today, a dairy farmer is most concerned about the health of their cows for maintaining a good supply of milk. Three main areas of focus include a nutritious diet, healthy living conditions, and good medical care for the dairy cows. Most importantly farmers must provide a healthy diet of 100 pounds of food and 25 - 50 gallons of water each day for his/her dairy cows. An animal nutritionist can aid a farmer in creating a feed formulated with the correct nutrients for a well-balanced diet. Dairy cows also spend time in a pasture for grazing and acquiring fiber for their herbivore diets. Today, the following tools and technology are used to provide delicious dairy products such as milk, yogurt, cheese, and ice cream.
- Dairy cows are kept in comfortable conditions in and out of the milking parlor, a separate building where cows enter for milking 2-3 times a day.
- Dairy cows have access to feed as well as fresh, clean water 24 hours a day in a free-stall barn that allows cows to eat, drink, and sleep whenever and wherever they choose.
- The cows are milked 2-3 times a day by the use of milking machines that automatically and safely remove milk from the cow's udder.
- The milking machines transport milk directly from the cow to a refrigerated bulk tank, located on the farm where milk is cooled to between 38 to 45 Fahrenheit to preserve freshness and safety.
- Milk is transported to processing plants by tanker trucks that are equipped to haul milk under safe conditions.
- Farmers use ear tags that contain a number assigned to a particular cow to help maintain accurate health and milk production records.
- A methane digester is used to convert cow manure into methane gas burned into fuel to create electricity used on the dairy farm.
- On larger dairy farms a storage building called a silo is used to store silage, a high-moisture forage eaten by cows.
