Submitted to: Journal of Food Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/29/2016
Publication Date: 11/10/2016
Publication URL: http://handle.nal.usda.gov/10113/5695336
Citation: Fleischman, E.F., Kowalski, R.J., Morris, C.F., Nguyen, T., Li, C., Ganjyal, G., Ross, C. 2016. Physical, textural, and antioxidant properties of extruded waxy wheat flour snack supplemented with several varieties of bran. Journal of Food Science. 81:E2726-E27233. Interpretive Summary: Consumer appeal is of importance when introducing fiber into snack foods with intense colors and harder textures like purple bran. Consumers may enjoy an antioxidant-enriched puffed snack food as an alternative to other retail products with little fiber. Furthermore, extrusion technology provides an efficient and inexpensive way to manage wheat bran waste.
Technical Abstract: Wheat represents a ubiquitous commodity and while industries valorize 10% of wheat bran, most of this antioxidant-rich byproduct gets discarded. The objective of this study was to incorporate wheat bran into an extruded snack. Bran varieties from hard red spring, white club Bruehl, and purple wheat lines were added to waxy pen wheat flour (T. aestivum L) at replacement concentrations of 0, 12.5, 25, and 37.5% (w/w) (n=10). Extrudates were evaluated for antioxidant capacity, color, and physical properties. Results showed that high fiber concentrations altered several pasting properties, reduced expansion ratios (p<0.0001), yet created denser products (p<0.0001); these observations were especially apparent for white bran. Purple bran extrudates produced harder products compared to white and red bran treatments (p<0.0001). Extrudates produced using 37.5% (w/w) of each bran variety absorbed more water than the control. The Oxygen Radical Absorption Capacity (ORAC) assay, expressed as Trolox equivalents, showed that red (37.5%) and purple (37.5%) bran had higher values compared to the other treatments, and the control, white, and red bran treatments had less antioxidant activity after extrusion (p<0.0001) compared to purple bran extrudates. Hence, purple bran may serve as a viable functional ingredient in extruded foods. Future studies could evaluate how bran variety and concentration, extruded shape, and flavor influence consumer acceptance.