naa a22 4500 510725236 CHVBK 20180411082932.0 cr unu---uuuuu 180411e20131201xx s 000 0 eng 10.1007/s11947-012-0977-4 doi (NATIONALLICENCE)springer-10.1007/s11947-012-0977-4 Investigation of Growth and Shrinkage Mechanisms in Vapor-Induced Expansion of Extrusion-Cooked Corn Grits [Elektronische Daten] [Mario Horvat, Heike Schuchmann] The development of expansion models with good predicting capabilities requires experimental data and a more fundamental understanding of the vapor-induced expansion behavior in extrusion cooking. In this study, we used a conventional and also a high-speed camera to observe the radial and axial expansion behavior of extrusion-cooked corn grits. Image processing was performed with an automated evaluation code. The experimental setup consisted of a novel high-speed extruder, which enabled the determination of the influence of high screw speeds of up to 1,200rpm on extrudate growth and shrinkage. In addition to optical measurement of the expansion, moisture content and temperature development during growth and shrinkage were determined. Three distinct stages of expansion were observed: extrudate growth, short-term shrinkage, and long-term shrinkage. The initial extrudate growth rate fitted well with a linear regression. Especially the second stage of shrinkage occurring in a time range of 24h after the experiment showed that shrinkage is often underestimated in existing models. Furthermore, total shrinkage increased at higher screw speeds. The data obtained deliver new insight into expansion phenomena and can support the development of predicting models. Springer Science+Business Media New York, 2012 Extrusion cooking nationallicence Expansion nationallicence Bubble growth nationallicence Shrinkage nationallicence Image processing nationallicence Glass transition nationallicence Horvat Mario Institute of Process Engineering in Life Sciences, Section I: Food Process Engineering, Karlsruhe Institute of Technology, Kaiserstraße 12, 76131, Karlsruhe, Germany aut Schuchmann Heike Institute of Process Engineering in Life Sciences, Section I: Food Process Engineering, Karlsruhe Institute of Technology, Kaiserstraße 12, 76131, Karlsruhe, Germany aut Food and Bioprocess Technology Springer US; http://www.springer-ny.com 6/12(2013-12-01), 3392-3399 1935-5130 6:12<3392 2013 6 11947 https://doi.org/10.1007/s11947-012-0977-4 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11947-012-0977-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Horvat Mario Institute of Process Engineering in Life Sciences, Section I: Food Process Engineering, Karlsruhe Institute of Technology, Kaiserstraße 12, 76131, Karlsruhe, Germany aut NATIONALLICENCE 700 1- Schuchmann Heike Institute of Process Engineering in Life Sciences, Section I: Food Process Engineering, Karlsruhe Institute of Technology, Kaiserstraße 12, 76131, Karlsruhe, Germany aut NATIONALLICENCE 773 0- Food and Bioprocess Technology Springer US; http://www.springer-ny.com 6/12(2013-12-01), 3392-3399 1935-5130 6:12<3392 2013 6 11947 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer