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

there is no direct correlation published between amount of oil and shelf life, a
significant correlation has been shown between oil content with maturity, which itself
is related to flavor and shelf life potential (Sanders et al., 1993).
The compositional and structural differences in the proteins and sugars of
immature peanuts suggest that these components will react differently to processes
in manufacture (Sanders, 1989). Vercellotti et al. (1994) formulated a biochemical
model of carbohydrate turnover during peanut curing. Immature peanuts had more
low molecular weight reducing substances and oligosaccharides than the mature
peanuts at all stages during curing. In addition, during maturation, many enzyme-
catalyzed reactions occur by way of proteases, lipases, glycosidases, and
phosphatases to make flavor intermediates. This dependence on timing may
change the flavor compounds present in the final product (Sanders et al., 1993). As
a result of these compositional differences, the type of response to conditions such
as high temperature curing or freeze damage will also vary based on maturity
(Sanders et al., 1995).
The degree of maturity will also affect color development of the peanuts
during roasting. Immature peanuts brown at a lower temperature and more rapidly
than mature peanuts. Consequently, close control of roasting is needed to reach the
optimum Hunter L value of 50 ± 1 (Ory et al., 1992).
Immature peanuts also vary in their flavor profiles. In general, immature
peanuts are more susceptible to off-flavor formation than mature peanuts (Osborn et
al., 2001), and at a given temperature, immature peanut seeds have a higher level of
off-flavor production than mature seeds (Pattee et al., 1965). Immature peanuts
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