Basic Dairy Foods Manufacturing

1. The Arkansas Food Technology Educational Program Presents Basic Dairy Foods Manufacturing

2. Facts About Milk • Americans consumed nearly 20 billion gallons of milk in 2002. • Milk has been known by man in recorded history for over 5,000 years. • The average U.S. dairy cow produces 18,000 pounds (2090 gallons) of milk per year. • U.S. milk production is moving from the Northeast and upper Midwest to the Southwest and West following human population shifts. • Most milk is marketed through large, farmer owned cooperatives.

3. Milk Constituents • Milk is the lacteal secretion of cows. • Raw milk straight from the cow is 87.6% water and contains: • 3.6% fat • 4.9% lactose (milk sugar) • 3.2% protein (mostly casein) • .7% minerals (Ca and P) • Fat content is dependent on the breed of cow. • How well the cow is fed affects the protein content.

4. Milk is Produced on Dairy Farms • Cows are fed scientifically balanced rations of grain, silage, hay and pasture. • Cows are milked twice daily in sanitary facilities under health department inspection. • Cows are examined and tested for disease by veterinarians. • Milk flows from the milking parlor in glass pipelines and is stored in a refrigerated, stainless steel tank. • Milk is picked up every day or second day and transported to processing plants.

5. From Farm to Processing Plant Milk is transported under refrigeration to the processing plant in tankers such as this one. Tankers are stainless steel and vary in size from 1500 to 6000 gallons. http://www.photojournalistas.com/Sept-Oct_2002/Evaporated_Milk/Photo_Pages/knoxfarm3.html

6. Cream Separator The cream separator was invented by De Laval. This machine separates the lighter cream from the heavier skim. The production of low fat milk and high fat products such as half and half and whipping cream is accomplished by recombining cream and skim milk. http://park.org/Netherlands/pavilions/food_and_markets/cheese/creamery.html

7. Pasteurized Milk Pasteurization was discovered by Louis Pasteur. Milk is heated to 161° F and held at that temperature for 15 seconds. This process destroys all pathogenic and spoilage organisms, preventing the transmission of disease and helping to preserve the milk. http://www.foreverpure.com/flash_pasteurizer.htm

8. Milk Standards • Originally whole milk was the only product available to the consumer. • Current diet and health concerns have made reduced fat products more in demand. • More reduced fat milk is consumed than whole milk. • Milkfat standards for milk are: • whole milk: ≥ 3.25 %. • reduced fat milk: 2.0 %. • lowfat milk: 1.0 %. • skim milk: no measurable fat. • Flavored milks such as chocolate and strawberry must conform to the same fat standards.

9. What is homogenized milk, anyway? During processing, the milk is pumped through a machine called a homogenizer. The fat globules in the milk are broken into extremely small pieces. After homogenization the fat will not rise, preventing separation of the cream from the milk.

10. Milk Packaging Milk and milk products are packaged in glass, paper and plastic bottles. Popular retail sizes are 10 quart, 1 gallon, half gallon, quart, pint and half pint. It is also available in 5 and 6 gallon wholesale packages. http://park.org/Netherlands/pavilions/food_and_markets/cheese/creamery.html

11. Cream Creams are made by combining cream and milk in correct proportions to give the desired fat content. Half and Half is 10.5% fat and light or coffee cream is 19 % fat. Heavy or whipping cream is ≥ 36 % fat. www.counton.org/numberland/ 48/48.shtml

12. Cheese Production Cheese is manufactured from whole or skim milk by the action of bacteria and enzymes. Liquid milk is converted to cheese by removing whey to produce curds and molding the curd to form the cheese. Cheeses are aged to produce characteristic textures and flavors. www.aillweecave.ie/ ac-cheesemaking.htm

13. Cottage Cheese Cottage Cheese is manufactured from skim milk by the action of bacteria and enzymes. Dry cheese curd is produced by cooking the curds and whey then draining the whey. Creamed cottage cheese is made by adding a creaming mixture to the dry curd. www.lancewood.co.za/recipes/

14. Butter Butter is produced from cream by churning. Churning breaks down the milk/fat emulsion causing the fat to coalesce. Salt is added and the butter is worked or kneaded to produce the desired waxy texture. http://www.tillamookcheese.com/products/butter.html

15. Yogurt Yogurt is produced by fermentation with beneficial bacteria which produce lactic acid and the characteristic flavor. Plain yogurt is used in cooking. Fruit is added to create a light, cool dessert. royaltyfreeclipart.com/ food/food-3.html

16. Ice Cream Ice cream mix is made by adding sugar and flavoring to cream and milk. The mix is pumped to freezers and frozen. The soft ice cream is filled into consumer packages or bulk containers for dipping into cones. The filled packages are frozen in a cold room. virtual.clemson.edu/groups/foodscience/ icecreamtour.htm

17. Frozen Yogurt and Custard Frozen yogurt is produced from yogurt in ice cream freezing equipment. Sugar and flavorings are added. Frozen custard is made from milk, sugar and eggs with various flavorings. www.goodforyouyogurt.com/ treat.html

18. Sherbets and Sorbets Sherbet is a frozen dessert which contains milk solids but no fat. Sherbets contain fruit juices and are acidified giving a refreshing sweet/sour taste. Sorbets contain no milk and are made from fruit juice, sugar and water. Both are made in ice cream equipment www.robertsdairy.com/html/ other_products.htm

19. Frozen Novelties Frozen novelties include ice cream bars, fudge bars, stick ice pops, ice cream sandwiches and other trademarked items. The specialized equipment for manufacturing novelties can automatically produce up to 30,000 items per hour.

20. Evaporated and Condensed Milk To produce evaporated milk, whole raw milk is heated under vacuum to remove half of the water. It is then canned and sterilized. Condensed milk contains added sugar. Both products are shelf stable for long periods. www.my-meals.com/ProductExpress/ Default.aspx?ProductID=3804

21. Buttermilk Buttermilk was originally a byproduct of butter churning. Now buttermilk is made by fermenting skim milk with bacteria. The resulting product is salted and packaged. www.medosweet.com/fluids.htm

22. Sour Cream Sour cream is produced from fluid cream. Bacterial cultures are used to ferment the product. Acid is produced to lower the pH. Acid precipitates the casein, causing the thick body and texture. Flavor compounds are also produced giving the desirable sour cream taste and aroma. www.horizonorganic.com/products/ indexsourcream.html

23. Non-Fat Dry Milk Non-Fat Dry Milk is produced from skim milk by removing the water in a spray dryer and collecting the powder. NFDM is packaged for the retail consumer and in bulk for use as an ingredient in many foods. www.quinnindia.com/infra.html

24. Nutrients in Milk • Three glasses (24 oz) of milk provides 100 % of calcium daily values and 20 % of protein daily values. • Milk is fortified to provide 20 % of Vitamin A and 75 % of Vitamin D daily values. • Milk contains traces of other nutrients and is a good source of energy in the form of fat and carbohydrates.

25. Calorie Content of Dairy Foods

26. Summary • The modern dairy industry produces safe, nutritious products for the consumer. • Milk can be manufactured into many different foods. • Milk is a excellent source of nutrients.

27. Produced and narrated by Jim Goff For further information contact: Jim Goff University of Arkansas Institute of Food Science and Engineering 2650 N. Young Avenue Fayetteville, AR 72704 (479) 575-3095 FAX (479) 575-2165 jgoff@uark.edu

28. For more information on Food Science contact: Steve Seideman, PhD Extension Food Processing Specialist Cooperative Extension Service University of Arkansas 2650 N. Young Avenue Fayetteville, AR 72704 (479) 575-4221 FAX (479) 575-6936 seideman@uark.edu