Abstract SCHIRACK, ANDRIANA VAIS. The Effect of Microwave ...

correlation with sensory preference (Buckholz et al., 1980). Young and Hovis (1990)
related compounds identified by GC-MS to flavor profiles in roasted peanuts: N-
methyl pyrrole was correlated with a musty off-flavor; pentane, acetone, and
dimethyl sulfide with a musty aftertaste; 2-methylpropanol with fruity; 2-butanone
with degree of roast; pentanal with tongue or throat burn; and hexanal with beany
flavor. Likewise, Vercellotti et al. (1992) monitored sulfur compounds such as
hydrogen sulfide ("rotten eggs" off-flavor), methyl sulfide (burnt cabbage), dibutyl
sulfide (rotten onion), dimethyl sulfide (cooked cabbage), dimethyl trisulfide (burnt
cabbage or onion), allyl sulfide (garlic-like) using FPD detection. These compounds
are detectable at thresholds less than 1 ppb, and add positively to the overall
bouquet at very low concentrations.
Gas Chromatography – Olfactometry (GC-O)
Although traditional GC techniques will determine volatile compounds present
in a sample, only a small percentage of these will be odor-active. Furthermore, the
relative amount of a compound in a food does not necessarily equal its sensory
impact. This can be due to matrix effects through which the compounds are
suppressed, but also depends on human thresholds for the compound. As a result,
GC-Olfactometry techniques have been used to bridge the gap between analytical
chemistry and sensory analysis.
The use of GC-Olfactometry was explored in the 1970's (Acree et al., 1976).
The GC-O technique follows volatile extraction from the product and allows a portion
of the column effluent to reach a "sniffing" port, while the other portion is routed to
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