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

ABSTRACT
Peanut blanching consists of heat application followed by abrasive removal of
the seed coat. The use of a continuous microwave system for the blanching of
peanuts has been proposed as a means of reducing processing time and energy
costs compared to the traditional hot air, multi-zone oven. The purpose of this
research was to characterize effective processing parameters for microwave
blanching. The factors examined were the time of exposure in the microwave, use
of increased airflow in the microwave applicator during processing, and the initial
moisture content of the peanuts. Processing treatments were differentiated by
energy absorbed during processing, average and maximum internal temperatures,
loss in moisture content, and blanchability. High blanchability resulted from higher
process temperatures and greater loss in moisture content. Treatments exceeding
110 °C resulting in a final moisture content of 5.5 % or below yielded blanchability
percentages greater than the 85 % industry standard. The time required to generate
sufficient heat to dry peanuts for acceptable blanchability is greatly reduced by the
use of microwave technology.
INTRODUCTION
Peanut blanching consists of heat application followed by abrasive removal of
the seed coat. Removal of the seed coat prepares peanuts for further processing
into specific products, and the heating step reduces enzyme activity and moisture
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