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Unit 1 The Science of Food
Purpose
You usually use a combination of senses to identify foods. In
this experiment, you will look at the role your sense of smell plays
in evaluating food products. You will examine how accurately you
can identify foods by only their aromas.
Equipment
blindfold
Supplies
a shoebox containing coded food samples in portion cups with lids
Procedure
Choose a lab partner or work with the partner your teacher assigns
you. Determine which of you will identify aromas fi rst and which
will record the data. The partner who is recording the data will
follow the steps of the procedure.
1. Blindfold the partner who will be identifying aromas.
2. Open the shoebox and remove one container. Open the lid and
hold the container in front of your partner.
3. Have your partner wave his or her hand over the container to
direct the aroma toward his or her nose. Ask your partner to
identify the aroma he or she is smelling.
Experiment 3A
Odor Recognition
Safety
• Do not taste samples.
• Do not smell samples directly when
identifying aromas. Some foods are
lightweight powders, which could easily
be inhaled. Instead, wave your hand over
the top of the container to direct the aroma
toward your nose.
• Do not move around when blindfolded.
81 Chapter 3 Sensory Evaluation: The Human Factor
4. Record your partner’s answer in a data table next to the appropriate
code number. Do not name code numbers or give any indication
as to whether your partner’s answer is correct. Close the
container and set it aside.
5. Repeat steps 2 through 4 until all samples have been tested.
6. Return all samples to the shoebox and exchange places with
your partner.
7. Repeat steps 1 through 5.
Data
When all students have completed the lab, your teacher will read the
key. Check to see how many aromas you correctly identified. Compile
your responses with those of your classmates into a class data table.
This table should show how many students in each test group correctly
identified each sample. Compare your correct answers with those of
your classmates.
Calculations
Use the information in the class data table to prepare a bar graph.
This graph should compare the correct responses in each test group
and the total correct responses for each sample.
Questions
1. Which aromas gave you the most difficulty? Which aromas gave
your classmates the most difficulty?
2. Which food was most often identified correctly?
3. Why did some students have more difficulty than other students
with this task?
4. Were the responses of the second member of each pair more or
less accurate? Why?
5. Is taste or aroma more important in food identification? Explain
your answer.
Three Challenging Experiments per Chapter
Science principles that will be
illustrated during the experiment.
S i i i l
Purpose
Reminders to use special
care with certain steps.
R i d t i l
Safety Cautions
Directions for recording
the results you observe.
Di ti f
Data
Everything you will need to perform
the experiment.
E thi ill d t f
Equipment
and
Supplies
Step-by-step instructions for
conducting the experiment.
St b t i t t
Procedure
Draw conclusions based on text
content and your observations.
D l i b
Questions
Apply scientifi c formulas
to the data collected.
A l i tifi f l
Calculations