Casein plastic, or “milk plastic,” has been used in the Americas for decades due to its low production costs and accessibility. Casein is defined as “a white, tasteless and odorless protein precipitated from milk by rennet” (“Casein” 1). and “a slowly 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. Although there are many ways casein has been used throughout history, the most popular ways this protein has been manipulated throughout history are in plastics, foods, and nutritional supplements. Casein is found in all mammalian milks, accounting for 80% of the proteins found in cow's milk and between 25 and 40% of the proteins found in human milk. This valuable protein is separated from milk by a practice called ultrafiltration (“Casein Protein” 1). Because casein is somewhat insoluble, it often forms structures called "micelles" that increase water solubility. Simply put, micelles are a mass of molecules in a colloidal mixture. When milk is pasteurized, the heat disrupts the casein and micelle structures, breaking them down to form simpler structures. Casein is made up of a group of similar phosphoproteins found in mammalian milk fat. Casein is a very important nutrient required for most life forms, especially for the young and elderly (“Casein Protien.” 1). Casein, as noted above, is a popular nutrition enhancer, generally considered to be a compound called caseinate. Caseinate is the result of casein and a common nutritional element, the most common being sodium and calcium. Caseinates have spectacular properties... middle of paper ...... have always been a commonly used product, whether today or thousands of years ago. Works cited “Plastic casein”. The Plastic Dealer. Np, and Web. November 7, 2013. “History of plastics”. SPI. Np, and Web. November 7, 2013. “Suzy’s world: plastic”. Suzy's world: plastic. Np, and Web. November 7, 2013. “American Art Plastics: Casein.” American Art Plastics: Casein. Np, and Web. November 11, 2013. “Facts You Need to Know About CASEIN” 2 Steps 2 Health RSS. Np, nd Web. Nov. 11, 2013. “Casein. » The Free Dictionary. Farlex, nd Web. December 4, 2013. » Casein Protein." Information. Np, nd Web. December 4, 2013. "Positive effects on children: Whey vs. Casein." National Center for Biotechnology Information. US National Library of Medicine, nd Web. December 6, 2013."Sodium Caseinate." Sodium caseinate. Np, nd Web. December 9.. 2013.