Probably the most critical item in sensory evaluation is defining the objective, exactly what is it that needs to be determined? The need to know whether or not two samples are different in character (such as in an ingredient substitution) is a different task from knowing which one is preferred. The test objective will determine the type of panelist, methodology, appropriate level of statistical risk to endure and how to interpret results to provide an actionable recommendation. All sensory testing can be defined under two categories: Affective Testing and Analytical Testing.
This includes acceptance/preference testing: Which sample do you prefer?. . . How much do you like it? What don’t you like? In order to answer these kinds of questions, true consumers are required. “Consumers” are special individuals who are pre-screened to be actual users of the product tested, they are not hungry employees or students who happen to wander in to taste!
Consumer testing is not always the best approach to use. For example, it is an expensive way to determine whether two samples are simpIy “different,” such as in an ingredient reformulation. Nonetheless, some assessment of consumer response to “new” products or “improved" (changed) products is generally advisable.