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

1969). The flavor characteristics of major headspace volatiles in raw peanuts were
identified as musty aftertaste, fruity, and musty (Young and Hovis, 1990). A
combination of γ-butyrolactone, benzaldehyde, indene, 2-methoxy-3-
isopropylpyrazine, nonanal, benzyl alcohol, and alkyl-substituted benzenes have
also been associated with the legume-like flavor (Fischer and Grosch, 1981). In
addition, high amounts of raw/beany flavor in the raw peanuts have been correlated
with methanol and ethanol concentrations (Crippen et al., 1992).
Flavor Production During Roasting
The unique flavor of roasted peanuts drives product marketing in the peanut
industry. This flavor is the result of genetics, production and handling, storage, and
processing factors (Sanders et al., 1995). The basic characteristics of roasted
peanut flavor have been described as nutty, stemming from the presence of
methylpyrazine, 2,6-dimethylpyrazine, and 2-methyl-5-ethylpyrazine; cheesy, from
isobutyric and valeric acids; and garlic, from sulphides present in the peanuts (Lee,
1980). The thermal products of the roasting process contribute to the unique peanut
flavor, and are affected by environment during storage and the initial mix of flavor
precursors (Vercellotti et al., 1994). Non-enzymatic carbonyl-amine browning and
lipid oxidation reactions are the sources of volatile flavor compounds in peanuts, and
include interactions between peanut components as well as thermal decomposition
products and loss of volatiles (Hoffpauir, 1953; Warner et al., 1996).
Maillard reactions are primarily responsible for browning reactions in roasted
peanuts, although caramelization of sugars plays a minor role. The products of
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