2.3. Procedure
Subjects participated in one-hour testing sessions once a week
during 6 weeks at 10:30 am, 3 pm or 5:30 pm. However, each subject
came each week at the same hour of the day to avoid individual
variability between weeks. Subjects were asked to avoid food
consumption 2 h before the test to reduce variations between subject
hunger levels. All tests were conducted in standardised individual
white partitioned booths, lighted with artificial red light
to hide possible appearance differences between samples.
For each subject, six testing sessions were necessary to test all
the variants of the study, even the two ranges of products not presented
in this article. During the first two sessions, biscuits were
cut and samples of one or two mouthfuls were served to ensure
that the total quantity consumed was not too much. Subjects
tasted between twelve and fifteen samples per session and
recorded their liking on a nine-point hedonic scale, from‘‘I extremely
dislike’’ to ‘‘I extremely like’’. During the last four sessions, biscuits
were cut and samples of three or four mouthfuls were served.
Subjects tasted between six and nine samples per session. They
ate each sample in three mouthfuls and after each bite, to rate
(a) crispiness, (b) sweetness and (c) fat perception on a five-point