Submitted to: Institute of Food Technology
Publication Type: Abstract Only
Publication Acceptance Date: 8/1/2007
Publication Date: 8/1/2007
Citation: Greene, J.L., Sanders, T.H., Drake, M. 2007. Characterization of flavor profiles and volitile compounds responsible for natural and artificially created fruity/fermented off-flavor in peanuts. Institute of Food Technology. Abstract.
Technical Abstract: The off-flavor in high-temperature-cured peanuts has been described by descriptive sensory analysis as fruity/fermented (FF). Published results using artificially created samples indicated that ethyl-2-methylpropanoate, ethyl-2-methylbutanoate, ethyl-3-methylbutanoate and hexanoic, butanoic, and 3-methylbutanoic acids were responsible for this flavor. However, these results have not been confirmed in naturally occurring FF peanuts. Sensory analysis in our lab revealed differences in the flavor profiles of natural and artificially created FF peanuts. The objective of this work was to characterize the aroma volatiles responsible for naturally occurring fruity fermented off-flavor in peanuts. Several FF samples were obtained from a commercial sheller and samples with no FF (0) and high FF (3) intensities were selected by a trained descriptive sensory panel. Mature and immature peanuts were cured at 27 C and 40 C to a moisture content of 8% which resulted in FF in the immature peanuts. Peanuts were roasted to L* = 55. Peanut samples were processed into paste, evaluated by a descriptive sensory panel, and the volatile compounds were extracted using solvent assisted flavor evaporation (SAFE). Gas chromatography/olfactometry and gas chromatography/mass spectrometry were used to identify and characterize the volatile components. Flavor profiles of the created and natural FF samples were distinct. The term rotten was selected by the panel as the descriptor for artificially created off-flavor peanuts while the term fruity/fermented, used in the standardized peanut lexicon, described the natural FF samples. Previously identified compounds in the artificially created samples were confirmed; however, these compounds were not found in the natural FF samples. The key differences between no FF and natural FF peanuts were characterized by differences in sweet aromatic compounds including 3-methylbutanal (sweet/malty) and pyrazines (roasted/nutty). These results suggest that caution should be exercised when using results from lab-created samples to identify sources of off-flavors in natural samples.