Casein plastic, or "milk plastic", has been used in the Americas for decades, thanks to its low production costs and accessibility. Casein is defined as “A white, tasteless and odorless protein precipitated from milk by rennin” (“Casein” 1). and “a slow-digesting protein that plays an important role in preventing muscle breakdown” (“Casein Protein” 1). Not only is casein an important protein that all mammals need to survive, but this vital protein has also been very important throughout recent American and English history. While there are many ways that casein has been used throughout history, the most popular ways that this protein has been manipulated throughout history have been in plastics, foods, and dietary supplements. Casein is found in the milk of all mammals, making up 80% of the proteins found in milk. cow's milk and anywhere from 25 to 40% of the proteins found in human milk. This precious protein is separated from milk through a practice called ultrafiltration (“Casein Protein” 1). Because casein is somewhat insoluble, it often forms structures called “micelles” that increase water solubility. Micelles, simply put, are a mass of molecules in a colloidal mixture. When milk is pasteurized, the heat causes the casein and micelle structures to be disturbed, thus breaking them down to form simpler structures. Casein is composed of a group of similar phosphoproteins found in mammalian milk fat. Casein is a very important nutrient required for most life forms, especially the young and old (“Casein Protien.” 1). Casein, as stated above, is a popular nutritional enhancer, commonly seen as a compound called caseinate. Caseinate is the result of casein and a common nutritional element, the most common being sodium and calcium. Caseinates have a show... in the middle of the paper... they have always been a commonly used product, both today and thousands of years ago. Works mentioned "Casein Plastic". The Plastiquarium. Np, nd Web. November 7, 2013."History of plastic." SPI. Np, nd Web. 07 November 2013. "Suzy's World: Plastic." Suzy's world: plastic. Np, nd Web. 07 November 2013. "American Art Plastics: Casein." American Art Plastics: Casein. Np, nd Web. November 11, 2013."Facts You Need to Know About CASEIN" 2 steps 2 RSS health. Np, nd Web. November 11, 2013."Casein." The free dictionary. Farlex, nd Web. 04 December 2013. "Casein protein." Information. Np, nd Web. December 4, 2013."Positive Effects on Children: Whey vs. Casein." National Center for Biotechnology Information. United States National Library of Medicine, nd Web. December 6, 2013."Sodium Caseinate." Sodium caseinate. Np, nd Web. 09 Dec. 2013.