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

GC-O Applications
High vacuum distillation (HVT), GC-O, and AEDA were used to evaluate the
volatile components of nonfat dry milks subjected to varying heat treatments
(Karagul-Yuceer et al., 2001). HVT, GC-O, and AEDA were also used to evaluate
the typical aroma components of British Farmhouse Cheddar cheese (Suriyaphan et
al., 2001). Aroma extract dilution analysis and GC-O were used to analyze volatiles
created during coffee roasting (Czerny and Grosch, 2000). In peanut research, GC-
O was used to generate "aromagrams" correlating odors and peak identities from
GC analysis of roasted peanuts (Vercellotti et al., 1992b). Likewise, Matsui et al.
(1998) used AEDA through GC-O on headspace samples to identify 2-ethyl-3,5-
dimethylpyrazine, 2,3-diethyl-5-methylpyrazine and 1-penten-3-one to have the
highest flavor dilution factors in commercially processed peanut oil.
After linking analytical data with sensory data through GC-Olfactometry
techniques, threshold analysis can be conducted to gauge human perception of
these compounds. To correlate with sensory, compounds found by chromatographic
analysis must exceed human thresholds. For example, the compounds
methylpropanal, methylbutanal, N-methylpyrrole, hexanal, hexanol, 2-pentylfuran,
vinylphenol, and decadienal were determined to have thresholds below the levels
found by FID in roasted peanuts, and therefore will have an effect on the flavor
(Vercellotti et al., 1992).
A final step might include the addition of specific compounds into a
deodorized model system, to analyze creation of the flavor note. A model is created
that matches the original sample aroma, and this can be the starting material for
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