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

cdry = Specific heat of dry seeds (1.880 kJ / (kg °C))
Tf and Ti = Final and initial temperature of seeds (°C)
mci and mcf = Initial and final seed moisture content (wb)
cw = Specific heat of water (4.187 kJ/(kg °C))
hlg = Heat of vaporization of water (2.418 x 104 kJ/kg at 35 °C)
The curing of peanuts at temperatures above 35 °C has been associated with
anaerobic by-products which produce an off-flavor (Whitaker et al., 1974). An
increase in the concentration of alcohols, aldehydes and esters, especially ethanol,
ethyl acetate, and acetaldehyde, is thought to be tied to this change in respiration
from aerobic to anaerobic (Pattee et al., 1990). At the high rates of respiration
occurring at high curing temperatures, oxygen cannot diffuse into the seed at a
sufficient rate, causing anaerobic respiration to take place. This was shown in an
experiment by Whitaker et al. (1974), in which a significant depression in oxygen
partial pressure was found inside peanuts cured at 52 °C compared to those cured
at 24 °C.
With increasing curing temperature, positive attributes such as roasted
peanutty decreased and fruity fermented intensity increased (Sanders et al., 1990).
Volatiles such as mercaptans, carbon dioxide, and carbonyls also increased during
roasting after high temperature curing (Young, 1973). Drying temperatures above
35 °C are avoided to prevent off-flavor formation (Troeger, 1982).
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