Question on ipm: A case study on lemon juice
Résumé
In food product development, using consumers to obtain ideal products is becoming more frequent in
recent years. Despite being an economical way of optimizing products, relying on consumers is,
however, not yet widely accepted in the sensory community. The main objectives of this study were to
evaluate (1) whether the stability of ideal intensities and ideal products could be improved by
providing a frame of references when consumers perform the Ideal Profile Method (IPM) and (2) the
effect of the order of the questions on consumers‘ responses.
In the present study, sixty participants conducted two tasks: (1) rating the perceived and ideal
intensities of attributes and (2) reporting the overall liking. They were randomly divided into four
groups. Group G1 and G2 used references in rating intensity, whereas group G3 and G4 did not.
Concerning the order of question, group G1 and G3 answered the overall liking question before rating
the intensity, whereas G2 and G4 followed the inverse order. The experimental design included six
lemon juice samples, and four attributes (pulp, lemon odor, sweetness, and sourness). A three-way
ANOVA was conducted on the ideal intensities of attributes and overall liking with reference and
order as a between-subject factor and product as a within-subject factor.
Results showed that providing a frame of references improved the stability of the ideal attribute pulp,
but not of the other ideal attributes. Besides, the order effect was without influence on overall liking.
For ideal intensities, an order effect was observed on the ideal attribute pulp between groups G3 and
G4 (without reference), and was not observed between groups G1 and G2 (with references). Several
possible modifications to improve the IPM are discussed.