Science Inquiry ProjectScience Inquiry Project Dilution Vs. Taste :Dilution Vs. Taste :Testing the Taste ThresholdTesting the Taste Threshold

Alex Becker Alex Becker

Pd. 3Pd. 3

I. IntroductionI. Introduction

• In my experiment I intend to research In my experiment I intend to research how diluting a substance affects how diluting a substance affects someone's ability to taste it. I will start someone's ability to taste it. I will start with 10% dilutions of sugar, salt and with 10% dilutions of sugar, salt and vinegar. I will then dilute each substance vinegar. I will then dilute each substance by a factor of ten each time until my test by a factor of ten each time until my test subjects can no longer taste the subjects can no longer taste the substance. substance.

II. HypothesisII. Hypothesis

•If I dilute sugar, salt, and If I dilute sugar, salt, and vinegar, then my taste vinegar, then my taste threshold for vinegar will threshold for vinegar will be the highest.be the highest.

III. MaterialsIII. Materials

• Iodized SaltIodized Salt• Granulated SugarGranulated Sugar• Distilled White VinegarDistilled White Vinegar• Distilled WaterDistilled Water• Stirring SpoonsStirring Spoons• Gram BalanceGram Balance• mL Measuring SyringemL Measuring Syringe• Paper CupsPaper Cups• Paper TowelsPaper Towels• ¼ Tablespoon Measuring Spoons¼ Tablespoon Measuring Spoons

IV. ProcedureIV. Procedure

1. Gather Materials.1. Gather Materials.2. Set up the balance scale and syringe for 2. Set up the balance scale and syringe for

measuring liquid.measuring liquid.3. Set out paper cups and label them with the 3. Set out paper cups and label them with the

percentage of dilution and the substance you percentage of dilution and the substance you are diluting. Ex. Salt, Sugar, Vinegarare diluting. Ex. Salt, Sugar, Vinegar

4. Measure 90 ml of distilled water using the 4. Measure 90 ml of distilled water using the syringe and pour it into a paper cup. Add 10 g syringe and pour it into a paper cup. Add 10 g of granulated sugar. Stir until dissolved. This of granulated sugar. Stir until dissolved. This gives you a 10% sucrose solution. gives you a 10% sucrose solution.

Procedure ContinuedProcedure Continued

5. Rinse your mouth with plain tap water 5. Rinse your mouth with plain tap water and wipe your tongue dry with a clean and wipe your tongue dry with a clean paper towel. paper towel.

6. Using a ¼ tablespoon measure, fill it 6. Using a ¼ tablespoon measure, fill it with the 10% sucrose solution. Pour the with the 10% sucrose solution. Pour the contents into your mouth to see if you contents into your mouth to see if you can taste the sugar.can taste the sugar.

Procedure ContinuedProcedure Continued

7. Write down whether you can taste the 7. Write down whether you can taste the substance or not (it is helpful to create a substance or not (it is helpful to create a data table to collect results.)data table to collect results.)

8. In order to dilute the 10% solution, measure 8. In order to dilute the 10% solution, measure out 10 ml of the 10% solution and pour it into a out 10 ml of the 10% solution and pour it into a clean paper cup. Add 90 ml of distilled water clean paper cup. Add 90 ml of distilled water and stir (use a clean stirrer or spoon so that and stir (use a clean stirrer or spoon so that you don't carry over concentrated solution into you don't carry over concentrated solution into the dilute solution.) This will give you a 1% the dilute solution.) This will give you a 1% solution.solution.

Procedure ContinuedProcedure Continued

Note: To dilute solutions you always Note: To dilute solutions you always take 10 mL of the previous solution take 10 mL of the previous solution and mix it with 90 mL of distilled and mix it with 90 mL of distilled water. Also, to create a 10% water. Also, to create a 10% vinegar solution use 2 ml of vinegar solution use 2 ml of vinegar and 18 ml of water. vinegar and 18 ml of water.

Procedure ContinuedProcedure Continued

9. Repeat dilutions as necessary and 9. Repeat dilutions as necessary and repeat experiment with all repeat experiment with all substances that you are testing. substances that you are testing.

Experiment SetupExperiment Setup

During The ExperimentDuring The Experiment

GraphGraph

0

0.5

1

1.5

2

2.5

3

People

Who Could

Taste

10% 1% 0.10% 0.01%

Percentage of Dilution

Salt

Sugar

Vinegar

Salt DataSalt Data

• Can Taste= Can’t Taste= Can Taste= Can’t Taste=

DilutionDilution10%10% 1%1% 0.1%0.1% 0.01%0.01%

AlexAlex

MomMom

DadDad

Vinegar DataVinegar Data

DilutionDilution10%10% 1%1% 0.1%0.1% 0.01%0.01%

AlexAlex

MomMom

DadDad

Can Taste= Can’t Taste=

Sugar DataSugar Data

• Can Taste= Can’t Taste= Can Taste= Can’t Taste=

DilutionDilution10%10% 1%1% 0.1%0.1% 0.01%0.01%

AlexAlex

MomMom

DadDad

Analysis/ConclusionAnalysis/Conclusion

I disproved my hypothesis during the I disproved my hypothesis during the experiment. I believed that the vinegar experiment. I believed that the vinegar was going to be the most bitter and was going to be the most bitter and easiest to taste throughout the dilutions. easiest to taste throughout the dilutions. However, after the 10% dilution I could However, after the 10% dilution I could no longer even taste a hint of it in the no longer even taste a hint of it in the water. Based on my data, salt was the water. Based on my data, salt was the easiest to taste for all members easiest to taste for all members involved. involved.

Conclusion ContinuedConclusion Continued

After my experiment I realized that using After my experiment I realized that using paper cups and paper towels might have paper cups and paper towels might have influenced the ability to taste the influenced the ability to taste the substances being diluted, because of the substances being diluted, because of the chemicals used when processing the chemicals used when processing the paper. If I were to repeat the experiment paper. If I were to repeat the experiment I would use glass cups and would not I would use glass cups and would not dry my mouth with paper towels. dry my mouth with paper towels.

Conclusion ContinuedConclusion Continued

Also, I might not rinse my mouth with tap Also, I might not rinse my mouth with tap water, but rather distilled water. Tap water, but rather distilled water. Tap water could have trace chemicals in it water could have trace chemicals in it that might have influenced my ability to that might have influenced my ability to taste. Another change that I might make taste. Another change that I might make would be not using metal spoons, they would be not using metal spoons, they too could influence the taste of the too could influence the taste of the substances. substances.