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

the identification of volatile compounds, gas chromatography-mass spectrometry
(GC-MS) has been frequently used in flavor chemistry. In GC-MS, after the sample
is volatilized and separated in the GC column, fragments of specific mass and
charge are created by either electron or chemical ionization techniques. These ions
are accelerated and directed to a mass analyzer, where they are separated based
on their mass/charge ratio. Each molecule will yield a characteristic fragmentation
pattern used to identify the molecule, because the concentration of different ions
formed depends on their stability and bond energies. Analysis using the MS can
yield structural information about the molecule, the molecular weight, as well as the
chemical formula, depending on the type of MS technique used (Ravindranath,
1989).
Correlation to Quality and Sensory
Flavor volatiles which have been identified in the peanut profile have been
linked to the positive characteristics as well as the off-flavors found in peanut
products. Lovegren et al. (1982) found a good quality peanut to have the following
volatile profile: free methanol (2 ppm), methanol produced + acetaldehyde (1.5
ppm), ethanol (1.3 ppm), acetone (0.25 ppm), N-methylpyrrole (0.25 ppm), hexanal
(0.10 ppm), nonanal (0.10 ppm), total volatiles profile (8 ppm). Although the color of
roasted peanuts can be predicted using GC profiles, the characteristic roasted
peanut flavor note remains unpredictable by instrumental analysis (Ory et al., 1992).
Poor peanut sensory quality has been correlated to a high concentration of
certain volatiles. The harsh, green notes of pentanal were shown to have a negative
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