71A-41

A. CAUDLE, Y. Yoon, and M. A. Drake. Dept. of Food Science, North Carolina State Univ., Schaub Hall, Box 7624, Raleigh, NC 27695-7624

Skim milk powder (SMP) production in the U.S. is greater than one billion pounds annually. Domestically, the primary use for SMP is in ingredient applications, where it is used in a multitude of products. Flavor variability in SMP has been documented by descriptive sensory analysis and instrumental analysis; however, research has not addressed how or if SMP flavor variability impacts consumer acceptance of ingredient applications. The objective of this study was to determine if flavor variability in SMP impacted consumer acceptance of ingredient applications made with SMP. Descriptive sensory analysis was conducted on 30 reconstituted low heat SMP (4 mo to 4 yr old) using a previously established defined sensory language. Four SMP were selected for further testing. Two samples were free of off-flavors (flavor similar to fresh fluid skim milk) and two samples contained off-flavors (exhibiting flavors not found in fluid skim milk). Solid phase microextraction (SPME) with gas chromatography-mass spectrometry (GC-MS) was used to analyze volatile compounds of the selected SMP. Each SMP was subsequently directly reconstituted or incorporated into standard formulas for vanilla ice cream, strawberry yogurt, hot cocoa mix, and white chocolate bars. Consumer acceptance testing (n=100) was then conducted with each of these five applications. Descriptive panelists documented sweet aromatic and cooked flavors in the fresh-flavored SMP, and these flavors, as well as fatty/fryer oil and animal-like flavors, in the off-flavored SMP. Concurrently, instrumental volatile analysis revealed higher relative abundances of lipid oxidation compounds in the off-flavored SMP. Consumer acceptance scores were lower for the off-flavored SMP than for the fresh-flavored SMP when evaluated directly reconstituted (P < 0.05). Further, this trend was also consistent for ingredient applications made by using off-flavored SMP (P < 0.05). Off-flavors in SMP documented by descriptive analysis and trained panelists can carry through into ingredient applications and negatively affect consumer acceptability.

Session 71A, Dairy Foods: General
8:30 AM - 12:00 PM, Tuesday AM Room Hall I-2

2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana