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

microwave blanching (Table 1). A filled conveyor of peanuts (approximately 6 kg)
was exposed to the microwave field for 4, 5, 8, or 11 minutes in a continuous
process. The variation in microwave exposure times allowed for a range of internal
temperatures to be reached in the peanuts during heating. This translated into
peanuts which ranged from minimally blanched to those exhibiting high blanching
efficiency, as determined by the percentage of seeds with complete removal of the
testa (Table 1). Each of these treatments was processed both with (“F”) and without
a fan (“NF”). The use of a fan was explored due to the effect on temperature and
moisture content in the peanuts during heating. The control for these treatments
was a batch of peanuts which went through the same processing procedures but did
not receive microwave heating.
The treatments were replicated four times. Immediately after blanching,
peanuts were cooled to room temperature using forced ambient air. They then were
sealed in plastic bags, and stored in opaque containers in a cooler at 6 °C and 60%
relative humidity. The peanuts were processed into paste for sensory analysis
within 2 days of blanching.
Temperature Measurement During Blanching
Internal temperatures of the peanuts during blanching were measured using
four fiber optic probes (FOT- L/10M, Fiso Technologies, Inc., Quebec, Canada)
inserted into the center of individual peanuts as they traveled the length of the
conveyor. The probes were connected to a multi-channel fiber optic signal
conditioner (Model UMI 4, Fiso Technologies, Inc., Quebec, Canada) which was
controlled using FISO Commander software (Fiso Technologies, Inc., Quebec,
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