Author
Rosentrater, Kurt | |
MUTHUKUMARAPPAN, K - SOUTH DAKOTA STATE UNIV | |
JULSON, JAMES - SOUTH DAKOTA STATE UNIV |
Submitted to: Meeting Proceedings
Publication Type: Proceedings Publication Acceptance Date: 5/12/2006 Publication Date: 7/12/2006 Citation: Rosentrater, K.A., Muthukumarappan, K., Julson, J. 2006. Supercritical co2 extrusion – opportunities for food and biological processing. Meeting Proceedings from 2006 ASABE Annual International Meeting, Portland, Oregon, July 9-12, 2006. Interpretive Summary: Technical Abstract: Extrusion cooking is a high temperature, short time processing method. During extrusion processing, many chemical and structural changes of the feed materials occur inside the barrel due to high temperatures, shear rates, and pressures. These alterations affect bonding between molecules, which in turn influence resulting dough and final extrudate properties. An emerging technology in the food industry is extrusion processing with supercritical CO2 injection. This technique has become increasingly used in plastic polymer processing in recent years to aid the extrusion process as a plasticizer, solvent, and blowing agent. It has been shown to be particularly useful in the development of foams. At supercritical conditions, CO2 exhibits both liquid and gas properties, with low viscosities and high rates of diffusion, low flammability, low toxicity, and benign environmental effects. Upon exiting the extruder die, the CO2 diffuses into the atmosphere, and thus results in no solvent waste that requires remediation. Although supercritical extrusion has not yet found extensive use in the food industry, this technology does offer the potential to provide a mechanism for unique biological and chemical alterations in various products. Toward that end, existing literature, both in the polymer and food processing areas, will be critically reviewed and potential applications for value-added food and biological processing will be discussed. |