89-12 |
Extrusion processing of a ready-to-serve hydroponic sweet potato breakfast cereal |
M. Y. DANSBY and A. C. Bovell-Benjamin. Department of Food and Nutritional Sciences, Tuskegee University, 300 Campbell Hall, Tuskegee, AL 36088 Extrusion cooking of cereal is widely practiced, and the technology is base-lined to be used on long-term space missions by NASA. To date, there is little or no research regarding the development of an extruded sweet potato breakfast cereal. The objective of this study was to develop an extruded ready-to-serve breakfast cereal utilizing hydroponically grown sweet potatoes. Three cereal formulations consisting of 100% sweet potato flour (SPF), 75%/25% sweet potato and wheat flour (SPWF) and 100% whole-wheat flour (WWF) were prepared. Additional ingredients remained constant for the three formulations. The feed moisture contents for the SPF, SPWF, and WWF were 16.1%, 17.5%, and 22.3%, respectively. Specifications for the single-screw extruder used were: L/D ratio, 20:1 and die opening of 3 mm. The mixtures were manually fed through the hopper and extruded at 100°C, 120°C (metering zone), and 150°C (die) with a constant screw speed of 160 rpm. The moisture content, bulk density, water absorption and solubility indices, expansion ratio, and color were measured. The moisture content of the WWF was significantly higher (p< 0.05) than the SPF and SPWF cereals. Expansion ratio increased with increased sweet potato content. Water absorption index and water solubility index increased as moisture content increased for all cereals. The SPF had the highest L* (lightness) and a* (redness) values. Mean L* values for the SPF, SPWF, and WWF were 44.95±0.25, 43.49±0.25, and 39.74±0.13, respectively. Mean a* values were 8.81±0.07, 9.21±0.05, and 9.67±0.03, while mean b* values were 19.27±0.15, 26.67±0.24, and 24.25±0.19 for SPF, SPWF, and WWF, respectively. Consumers preferred the SPF, which had the lowest moisture content, greater bulk density, higher expansion ratio, and lighter color during informal bench-top testing. The extruded sweet potato breakfast cereal has potential to add variety to human diets, as well as to increase sweet potato consumption for consumers.
Session 89, Product Development
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