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

confections and peanut butter. The peanuts were also roasted to avoid interference
of the strong raw/beany note of unroasted peanuts with off-flavor detection
(Didzbalis and others 2004).
An 800 g sample for each replicate was roasted and processed into paste for
sensory and instrumental analysis. A thermostat-controlled Aeroglide Roaster was
used (Aeroglide Corporation, Raleigh, NC) to roast samples at 177 °C for the time
needed to achieve L values in the range of 48-52 (Vercellotti and others 1992) using
a Hunter LAB DP-9000 colorimeter (Hunter Associates Laboratory, Reston, VA).
Samples were ground into paste using a food processor (Cuisinart Little Pro Plus,
Cuisinart Corporation, East Windsor, NJ). A grind / cool protocol was used to
prevent overheating of the paste, as discussed by Sanders and others (1989).
Samples were kept frozen at -20 °C in glass jars until evaluation.
The peanut samples evaluated by instrumental analysis were selected based
on sensory analysis results. For descriptive sensory analysis, samples were coded
with three digit random codes, and evaluated against controls for each of four
processing replications. The sensory panel consisted of 10 panelists, each with at
least 40 h training in peanut sensory evaluation. Panelists were trained with the
Spectrum TM Descriptive Analysis method using a 15 point intensity scale (Meilgaard
and others 1999). Each sample was evaluated in duplicate by each panelist.
Samples were described using the peanut lexicon developed by Johnsen and others
(1988) and Sanders and others (1989), with the addition of some attributes identified
by the trained panel for these samples, such as ashy, as defined by the aroma of
cigarette ash; and total offnote, an attribute which encompassed all negative
146