Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/20/2003
Publication Date: 3/1/2004
Citation: KOZEMPEL, M.F., TOMASULA, P.M. DEVELOPMENT OF A CONTINUOUS PROCESS TO MAKE CASEIN FILMS. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY. 2004. V. 52(5). P. 1190-1195. Interpretive Summary: Calcium caseinate, a modified casein derived from milk protein, has unique physical properties that make it a desirable biodegradable polymer for use in films and coatings. Films made from casein, glycerol, (added to make the films more flexible) and water have properties not unlike those of films made from petrochemicals. It is relatively easy to make films in the laboratory by pouring a solution of casein, glycerol and water into a dish and allowing it to dry undisturbed to properly form a thin film. However, the technology for making these films on a large-scale is unknown. A process was developed to make casein films on a continuous or moving belt. Time, temperature, belt support material, and feeding mechanism were determined. The process can produce continuous films about 20 cm wide. This process establishes the potential for the commercial production of biodegradable polymer coatings made from dairy products.
Technical Abstract: A semi-continuous pilot plant process was developed to make films from Ca Caseinate plasticized with glycerol. Adjusting the glycerol concentration, the process produces films with properties similar to those previously reported for a batch process. Ca caseinate/glycerol solutions wetted and spread on polyethylene or Mylar belts and were readily removed after forming films. Ca Caseinate was used as a surrogate for casein prepared using high pressure CO2. CO2 casein has unique physical properties and batch prepared films are barely soluble and are slightly stronger and stiffer than corresponding Ca caseinate films. It is anticipated that this process will apply to CO2 casein and to other proteins and carbohydrates.