Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: April 1, 2004
Publication Date: July 14, 2004
Citation: Kozempel, M., Tomasula, P.M. 2004. IFT Annual Meeting. A continuous process for biodegradable protein films. Abstract No. 67-F. Technical Abstract: About 60 million tons of petrochemical-based films and coatings are produced annually with 32 million tons used in food packaging. The only successfully reported method for making protein-based films has been by a casting process that results in films with variable thickness and uneven properties. If the films can be made by a continuous process, they could command a significant market because they are not only readily biodegradable, but also edible. Objectives of this study were to develop a continuous process for making calcium caseinate films. The process developed should be applicable to other protein films. Our specific objective is to develop a continuous process to make CO2 casein-based films. CO2 casein has unique physical properties. CO2 casein films are barely soluble in water, are more resistant to high humidity, and are slightly stronger and stiffer than corresponding Ca caseinate films. To develop the continuous process, the drying parameters, suitable belt materials that permit the film solution to properly wet the surface, dry, and easily release, plus a suitable feed system were determined. Two belt materials were suitable - polyethylene and Mylar. The solutions easily wet the surfaces, spread uniformly and remained on the belt by surface tension. The dry film was easily removed. With repeat application, the film was still easily removable. A belt speed of 2.2 m/h and a feed rate of 18.3 g/m gave a fairly uniform film when dried. Drying time was a minimum of 5.5 h. The tensile strength ranged from 2 to 5 MPa and the % elongation ranged from 22 to 59. The film thickness was 0.11-0.15. Various large, major companies have expressed strong interest in the casein films but further interest was attenuated due to the limitations of cast films. With the advent of a continuous process, commercial potential should be significantly increased.