Influence of flavor variability in skim milk powder on consumer acceptability of ingredient applications

Flavor variability in skim milk powder (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. Twenty reconstituted low-heat SMPs were screened using a previously established defined sensory language. Two SMPs free of off-flavors (flavor similar to fresh fluid skim milk) and 2 SMPs exhibiting off-flavors (exhibiting flavors, not found in fluid skim milk) were selected for further study. Volatile compounds were determined using solid phase microextraction (SPME) with gas chromatography-mass spectrometry (GC-MS). 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 was conducted. 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) and for ingredient applications made using off-flavored SMP (P < 0.05). Off-flavors in SMP documented by descriptive analysis and trained panelists can carry through into ingredient applications with SMP and negatively affect consumer acceptability.