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

the detector. The compounds can then be identified by aroma descriptors in
combination with retention indices and identification by GC-MS. The main purpose of
GC-O is to order the aroma volatiles in a food matrix according to their potential
importance (Ferreira et al., 2002). Although it is possible that a flavor may result
from a single chemical compound, it is more commonly found that the perceived
flavor is a result of the interaction of several compounds. For example, Bendall
(2001) discovered differences in milk flavor caused by concentration differences in a
set of flavor compounds held in common by the two treatments, rather than selective
occurrence of compounds uniquely associated with a particular treatment.
The volatiles with the most impact on flavor have been identified using a
determination of threshold (CHARM or AEDA), measuring the frequency of citations
and by assessing intensity (OSME), and by cross modality matching (Ferreira et al.,
2002). Both Charm Analysis and AEDA are based on dilution of samples until an
odor is no longer detectable (Drake and Civille, 2002). The highest dilution at which
the odor is still detected is converted to a flavor dilution value (FD) in AEDA, or to a
Charm value. The charm algorithm gives an estimate of sensory intensity apart from
the complexities caused by psychological estimation of stimulus intensity (Acree et
al., 1984). However, these techniques require a large number of samples and
panelists, making the method time-consuming (Drake and Civille, 2002).
In AEDA (aroma extract dilution analysis), the flavor extract is sequentially
diluted at a certain rate (usually 2-, 3-, 5-, or 10-fold) and each dilution is analyzed
by GC-O by a number of judges. A dilution rate of 10 was shown to be the best by
simulations although lower dilution rates were advantageous if the compound had a
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