Submitted to: Meeting Abstract
Publication Type: Proceedings
Publication Acceptance Date: October 15, 2007
Publication Date: November 16, 2007
Citation: Tomasula, P.M., Bonnaillie, L.M., Qi, P.X., Van Hekken, D.L. 2007. Fractionation of Dairy Proteins Using High-Pressure and Supercritical Carbon Dioxide. In Proceedings at the International Conference on Traditional Dairy Foods, November 14-17, 2007, Karnal, India. p.3. Technical Abstract: While several methods have been proposed for isolating dairy proteins from milk or aqueous solution, one of the most promising uses high pressure or supercritical carbon dioxide. In our laboratory, high pressure carbon dioxide has been used to precipitate casein from milk in a continuous pilot plant process and supercritical carbon dioxide has been used to produce enriched fractions of the whey proteins from whey protein concentrate solutions. Fractionation is achieved through manipulation of system pressure, temperature and protein concentration, all of which in turn affect solvent pH. When carbon dioxide is dissolved into an aqueous solution under pressure, it hydrolyzes to form carbonic acid. Processes based on carbon dioxide do not require organic or acidic solvents to precipitate the proteins; may be more economical than other methods because relatively concentrated feed streams or milk, instead of dilute feed streams, may be processed; and, are environmentally friendly because the carbon dioxide may be recovered after separation has been achieved. While it was initially thought that the efficiency of the isolation or fractionation of the proteins was due to pH adjustment alone, other factors related to solvent dynamics also affect the fractionation process. This presentation will focus on the casein and whey fractionation processes as well as some of the properties of the proteins obtained from these processes.