Sensory evaluation may be done under formal restricted panel situations or under less formal consumer type situations. As with any situation which involves human subjective evaluation, sensory assessment is difficult and tends to be influenced by many factors unrelated to the food item being tested.
There are a number of different sensory tests as indicated by the following series of definitions.
Difference tests: In difference tests the panelists are merely asked if a
difference exists between two or more samples.
Preference tests: Preference or
acceptance tests determine representative population preferences and these tests inherently
require many people on the panel.
Triangle test: In the triangle test, three coded
samples are presented to the panelist. He/She is told that two samples are identical and he/she is
asked to indicate the odd one.
Duo-Trip test: In the duo-tro test, three samples are
presented to the taster. One is labeled "R"(reference) and the other two are coded. One coded
sample is identical with "R" and the other is different. The panelist is asked to identify the odd
sample.
Paired comparison test: In the paired comparison test, a pair of coded
samples that represent the standard or control and an experimental treatment are presented to the
panelist, who is asked to indicate which sample has the greater or lesser degree of intensity of a
specified characteristic, such as sweetness and hardness. If more than two treatments are being
considered, each treatment is compared with every other in the series.
Multiple
comparison: In multiple comparison tests, a known reference or standard is labeled "R" and
presented to the panelist with several coded samples. The panelist is asked to score the coded
samples in comparison with the reference sample.
Ranking: The panelist is asked
to rank several coded samples according to the intensity of some particular characteristic.
Scoring: Coded samples are evaluated by the panelist who records his reactions on a
descriptive graduated scale. These scores are given numerical values by the person who analyzes
the results.
Flavor-profile method: The flavor-profile method consists of a small
laboratory panel of 6 or 8 people trained in the method measure of the flavor profile of food
products. Descriptive words and numbers, with identifiable meaning to each panel member, are
used to show the relative strength of each note on suitable scale.
Dilution tests:
Dilution tests involve the determination of the identification threshold for the material under
study.
