Can Student's Identify Fruit Juices Better With Taste, Smell, or Both?

Researched by Molly C.
2003-04




Purpose

The purpose of this experiment was to determine if students could identify fruit juice better with taste only, smell only, or both taste and smell.

I became interested in this idea when I wondered why I couldn’t taste anything while I had a cold. 

The information gained from this experiment would benefit anybody with a cold so they know what fruit juices they can enjoy the most.



Hypothesis

My first hypothesis was that students would identify fruit juices better with taste and smell together.

My second hypothesis was that students would identify juice better with smell alone rather than taste alone.

My third hypothesis was that cranberry juice would be easiest to identify overall.

I based my first and second hypotheses on “Taste” an article in World Book Encyclopedia 1999, that said, “Our sense of taste is affected by how things smell.” 

I based my third hypothesis on the fact that I personally find cranberry juice very distinctive in taste.




Experimental Design

The constants in this study were:
* The juices tested
* The blindfolds used in the experiment
* The nose plugs used in the experiment
* The cups used in the experiment
* The amount of time given to each student
* The brand of the tested juices

The manipulated variable was the sense or senses that the subject used. 

The responding variable was the number of correct juice identifications. 

To measure the responding variable I tabulated the responses given by each subject, then counted the number or correct responses. 



Materials
 
 
 

Quantity Item Description
1 jug of orange juice
1 jug of apple juice
1 jug of cranberry juice
1 jug of lemonade
1 jug of grape juice
5 nose plugs
5 blindfolds
~180 Dixie cups
25 Alchohal swabs
 
 




Procedures

1. Distribute and collect parent permission slips to --- seventh grade classes to obtain subjects.
2. Randomly assign students to one of the test groups.

Prepare juices
1. The juices used in this experiment (apple, orange, lemonade, cranberry, and grape) will be purchased at a grocery store and are okay for human consumption.
2. Wash hands.
3. Pour the five juices into five separate small cups before your subjects enter the room.  You will also need five small cups of water, so they are able to rinse.

4. Test subjects first take 5 subjects and seat them. 
5. Read them the instructions and answer any questions they might have. 
6. Then blindfold them.
7. Tell your subjects to smell the juice that you gave them before they entered the room (either grape, apple, orange, lemonade, or cranberry).
8. Then by a raise of hands, have them indicate what they think the juice was that they just smelled.
9. When they are done smelling the first juice, repeat step 2 with the other four   drinks.

10. Now pass out nose plugs to each of your subjects and have each put it on. 
11. Repeat steps 2-7 with the subjects drinking with the nose plugs on.
12. Have them rinse their mouths after each juice is tested.
13. Next tell your subjects to take off the nose plugs, and repeat steps 2-4 by tasting the fruit juice. Remember to have your subjects rinse with water after they drink each juice.



 RESULTS

The original purpose of this experiment was to determine if students could identify fruit juice better with taste only, smell only, or both taste and smell.

The results of the experiment were that students could identify fruit juices better with taste and smell (4.12 on average), then smell (3.95), and then taste alone (3.85).




 CONCLUSION

My hypothesis was that students would identify fruit juices better with taste and smell together because the results indicate that my first hypothesis should be accepted. 

My second hypothesis was that students would identify juice better with smell alone rather than taste alone.

My third hypothesis was that cranberry juice would be easiest to identify overall.

The results indicate that my first and second hypotheses should be accepted, but my third hypothesis should be rejected. 

Because of the results of this experiment, I wonder if I would get the same results with the solid fruits, rather than their juices

If I were to conduct this project again I would use more test subjects and more juices because then my results would be more accurate.
 

Research Report

Introduction: 

Taste and smell are highly important for a human being. Without these two senses, we might not be able to tell the difference between poison and things we would normally consume, such as fruit juice. Fruit juice is “the extractable liquid that is contained in fruit or vegetables”. 

Taste: 

Taste helps humans determine what and how much they eat. A human’s sense of flavor is affected by how things smell. Taste buds are grouped on the tongue into small mounds called papillae. Each taste bud contains a number of receptor cells. The papillae on the front of the tongue are all connected to one nerve. This section of the tongue reads “sweet” molecules.  Overlapping the sweet taste buds, and going to about the middle of the back of the tongue are the taste buds, which are also connected to one nerve. Then comes salt, bitter, at the very back of the tongue (all connected to one nerve). Humans also have taste buds on the soft palate (the roof of your mouth). So when we consume food and drinks, the receptor cells pick up those certain molecules. From the receptor cells, all the nerves come together to the back part of the brain, the stem (thalamus).  That’s how a human knows the taste difference between many foods and drinks.

Smell:

The sense of smell is also very important to any human being. Without smell, you would not be able to taste as much. When you smell something, molecules from the air stimulate receptor cells deep inside your nose. This is the olfactory system. Your receptor cells send impulses created by an odor along the olfactory nerves. The olfactory nerves carry impulses to the olfactory bulb inside the brain. The impulses then go from the olfactory bulb, to the forebrain (the front part of the cerebrum). Then a part of the forebrain processes the impulses to information about the odor. 

Fruit:

Fruit comes from the Latin word frui, which means, “to enjoy”. Temperate fruits must have an annual cold season to grow properly. Most of them are raised in temperate zones. They grow in Europe, North America, Asia, and Australia.  Some examples of temperate fruits are apples, apricots, cherries, peaches, pears, plums, blueberries, cranberries, grapes, raspberries, and strawberries. 
 Subtropical fruits require mild temperatures and are grown in Subtropical regions.  Subtropical fruits are mostly citrus fruits, such as grapefruits, lemons, limes, oranges, but there are also dates, olives, avocados, and figs.
Tropical fruits include bananas, pineapples, cherimoyas, litchis, mangoes, mangos teens, and papayas.  These fruits are raised in the tropics and cannot stand even a light frost.

Summary:

Smell and taste are important because without one of them, we would hardly be able to taste anything.  Fruits are important in our everyday life because they provide a healthy diet. 

Bibliography

* Bennet, Jennifer. “Fruit” World Book Encyclopedia. 2002.

* Halpern, Bruce P. “Taste” World Book Encyclopedia. 2002.

* Halpern, Bruce P. “Smell” World Book Encyclopedia. 2002.

* Stevens, Charles F. “Nervous System” World Book Encyclopedia. 2002. 

* Your Body.  Mankota: Creative Education,1997. pp.14


ACKNOWLEDGEMENTS
 

I would like to thank the following people for helping make my project possible:
* My parents for helping me throughout the year with my project and so much more.
* The students who participated in my experiment. Without them, I couldn’t have done it.
* The teachers who allowed their students to participate in my experiment during class.
* Mr. Newkirk for providing tremendous help and tips for my research report as well as my experiment.
* Mrs. Helms for helping me with my table and graph, and supervising the experiment.
 


Top of page

Menu of 2003-2004 Science Projects

Back to the Selah Homepage