15F-25 |
Optimization of sensory characteristics and consumer acceptability for peanut-based extruded snack products using response surface methodology |
I. -. D. CHOI1, A. V. A. Resurreccion, and R. D. Phillips. (1) Food Science & Technology department, University of Georgia, griffin, GA 30223-1797 Snack foods are a significant part of America's diet, and today's consumers are demanding a broader selection of snack foods. We have previously reported the cell size measurements of indirectly puffed, peanut-based snacks produced by extrusion processing. The purpose of this study was to optimize composition and extrusion conditions and to characterize these snacks by descriptive sensory profiles and consumer acceptability. Mixtures of lightly roasted, partially defatted peanut flour -PF(30-50%), rice flour and salt(2%) were extruded at several screw speeds-SS and feed rates-FR in a 3x3x3 central composite experimental design. The extrudates were dried to obtain half-products with moisture content of 11-12%, and the half-products were expanded by deep-fat frying at 200°C for 40sec. Quantitative Descriptive Analysis(QDA) was used to characterize the sensory profiles by nine panelists, and consumer acceptance tests were conducted with 40 panelists evaluating each sample. The consumer acceptance data for 5 attributes were subjected to response surface methodology(RSM) to identify the optimum region, defined as the area in which each attribute had values >6.0. The amount of peanut flour was the most important factor affecting consumer acceptance followed by feed rates; whereas screw speed had less significant effects. The optimum range included all feed rates (4.0-6.0) and was bounded by PF values of 30.0-38.5% at FR=4.0; PF of 30.0-42.0% at FR=4.65 (Maximum of curve) and PF of 30.0-32.0% at FR=6.0. The sensory model was verified by an independent study. Acceptable attribute range for brown color was from 40.6 to 53.8; for crispness from 74.9 to 82.9; for hardness from 76.8 to 90.9; and for fracturability from 58.7 to 64.8. Some acceptable ranges of other descriptive sensory attributes were also estimated. These results indicate that both QDA and consumer tests may be used as effective techniques to evaluate quality of snacks.
Session 15F, Product Development
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