8. Blindfold (For Optional Extension)
Per Student:
1. One of These Things is Not Like the Other student handout
2. 5-oz. Cup of Sample A
3. 5-oz. Cup of Sample B
4. 5-oz. Cup of Sample C
5. 5-oz. Cup of water
6. 2 Saltine® crackers
7. Napkin
Safety:
Because students will be allowed to drink during the activity, precautions should be taken to prevent
materials from coming into contact with laboratory equipment or surfaces. Materials should remain in
cups or on clean napkins at all times.
Technology Connection:
Not applicable
Procedures:
Teacher Preparation:
Use the attached template to prepare a One of These Things is Not Like the Other student handout for
each student. For each student, label 4 cups “A,” “B,” “C,” and “water,” respectively. Remove all
labels and markings from the soft drink bottle. Label the 2-L bottle of Pepsi® “A.” Label one 2-L
bottle of Coca-Cola® “B” and the second “C.” Fill each cup roughly half full with the appropriate
sample.
Estimated Time:
30 minutes
Introduction:
Sensory evaluation, an important area of food science, is a tool used to analyze and interpret human
sensory responses to food products based on the five senses: sight, sound, smell, taste, and touch.
Sensory evaluation is used to improve existing food products or to determine consumer acceptability of
new food products. Several types of sensory tests are used. A triangle test is a difference test that is
used to determine whether there is a sensory difference between two products. For example, do
consumers detect a difference between generic and name-brand food items? During a triangle test,
panelists are presented with three samples and asked to identify the sample they believe to be different
from the other two. Data is compiled from a number of panelists and analyzed to determine whether
there is a detectable difference between the products. A detectable difference is often considered to be
one in which fifty percent or more of panelists are able to correctly distinguish the odd sample from the
other two. However, food companies and researchers may adjust these levels according to their
particular interests or needs.