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

peanut moisture content from 5.5 to < 4 % using temperatures of 87.7 °C for 45 and
60 minutes and 98 °C for 30, 45, and 60 minutes resulted in maximum blanchability.
Moisture content affects blanchability as well as stability and flavor quality of peanuts
(Adelsberg and Sanders, 1997; Katz, 2002).
Microwave processing has been explored as an alternative to traditional
blanching methods due to speed of operation, energy savings, and efficiency of
process control. Shorter heating times during processing lead to greater nutrient
retention, better quality characteristics such as texture and flavor, as well as
increased production (Giese, 1992). The use of vacuum drying and microwaves for
peanut processing has been studied in comparison to traditional methods (Delwiche
et al., 1986). In a study using a series of individual trays of peanuts passing through
a linear applicator, Rausch et al. (2005) examined the potential use of microwaves
for peanut blanching. In the current study, refinement of the microwave applicator
has allowed a solid bed of peanuts to be exposed to microwave energy in a
continuous process, using a processing technique similar to Boldor et al. (2005).
Processing a continuous bed of peanuts eliminated the heat reflection and focusing
effect observed by Rausch et al. (2005) and prevented wide variation in peanut bed
surface temperatures.
The use of microwave technology for blanching peanuts can result in large
decreases in processing time and subsequent cost savings. The purpose of this
research was to characterize effective processing parameters for microwave
blanching, using a range of factors including exposure time, use of increased air flow
in the applicator, and initial moisture content of the peanuts. Relationships between
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