Submitted to: International Food Technology Meeting Abstracts
Publication Type: Abstract only
Publication Acceptance Date: 7/10/2003
Publication Date: 7/1/2003
Citation: Cheng, M., Berrios, J.D., Tang, J., Swanson, B.G., Garnanez, R.J. 2003. Fiber supplements and the physical properties of legume extrudates. International Food Technology Meeting Abstracts. Interpretive Summary:
Technical Abstract: High fiber-supplemented functional snacks or breakfast foods could improve intake of dietary fiber in the U.S. The average intake of dietary fiber is only half of the recommended amount. However, fiber supplements may reduce the appearance and texture quality of extrudates. The objective of this study was to determine the physical properties of extruded combination of dietary fiber supplements and legume flours extrudates. Seeds of two legume cultivars, Yellow Split Pea (YSP), Red Chief Lentil (RCL) and apple pomace in wheat bran fiber were processed using a twin-screw extruder. The properties of extrudates containing apple pomace fiber and wheat bran fiber at different concentration levels (5%, 10%, 15% and 20%) were studied by determining expansion index (EI), relative diameter difference (RD), density, color and texture profiles of the corresponding extrudates. The texture profiles of extrudates were also compared with those of six commercial extruded snacks. It was found that fiber supplements decreased EI and increased the density linearly with increasing fiber concentrations. No significant differences in EI were observed between YSP and RCL EI. The addition of fiber reduced RD and slightly darkened the extrudates due to the fiber's brown color. Hardness and strength of extrudates increased significantly with increasing fiber concentration. Equivalent amounts of apple pomace fiber affected the physical properties of extrudates more than wheat bran, except for color. Pea and lentil were also extrudated and exhibited equivalent texture as commercial extruded snacks at similar moisture contents. This study indicated that fiber may reduce the quality of legume extrudates slightly, but have potential as a nutritional supplement in expanded foods based on legume flours.