The triadic preference test

• New triadic preference test is developed.
• Triadic preference test combines the placebo and test pair.
• Majority of consumers choose ‘No Preference’ option for the placebo pair.
• With triadic preference test, placebo pair screening is a viable proposition.

A triadic preference test was developed as an alternative to the paired preference test. The three stimuli in the test comprised a putatively identical placebo pair and a different stimulus. This was in contrast to the regular paired preference test that utilizes a placebo pair. Such a test requires the presentation of two pairs of stimuli: a putatively identical placebo pair and a test pair. The triadic preference test only requires one triad. With the regular test, the majority of consumers respond to the placebo pair with a preference response. It is generally assumed that these consumers are responding to extraneous factors: those factors that elicit a preference response that are different from the sensory attributes of the food under assessment. As an attempt to minimize the possibility of responses to extraneous factors when assessing the test pair, it has been suggested to only use those consumers who chose the ‘No Preference’ option for the placebo pair. However, this form of ‘screening’ is not viable because the resulting ‘screened’ sample size is greatly reduced to approximately one third. However, in the present study, with the triadic preference test, the resulting ‘screened’ sample size ranged 76.5–94% of the total. Thus, this form of ‘screening’ against consumers who demonstrated response to extraneous factors for the placebo pair, was now feasible.