Gordon Selling
Department of Agriculture Agricultural Research Service Peoria, USA
Title: Extrusion processing of zein to provide higher value with improved processability
Biography
Biography: Gordon Selling
Abstract
Corn protein (zein) is one of the main co-products of corn bio-ethanol production and is known to have good film forming properties. However, zein also has deficiencies that may limit its applicability in the food packaging market. The properties of zein based articles will change on exposure to moisture and chemical modification is necessary to reduce the impact of moisture. Various techniques have been developed to achieve improved properties, however much of this work has been done in solution. In order to develop a successful food packaging product, in addition to product value, the process being utilized must use the most economical techniques. Extrusion processing is perhaps the most economical method for processing polymeric materials. Research will be presented demonstrating how extrusion processing effects the properties of zein articles. Extrusion processing at temperatures of up to 140 C can be performed with minimal reduction in product value. Zein can be recycled using extrusion processing to deliver articles with good properties. The impact of temperature and recycling on zein was carried out at temperatures from 100 – 300 C and up to 7 passes through the extruder at an extrusion temperature of 140 C. Molecular weight, secondary structure, and tensile properties were measured under all sets of conditions. Zein can be altered chemically using reactive extrusion techniques to provide higher valued articles. Solvent resistance and tensile properties were evaluated on the chemically altered zein. The information presented will be of value to scientists and companies interested in utilizing extrusion processing of their biobased materials.