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Members:Terence Tay (33) & Augustine Ting (34) Class:3Edward

PW 2.2 Food Test (Health Drinks)

Objective of Experiment:1) To carry out an investigation to compare the nutritional value of two sports drinks.

2) To carry out an investigation to determine which drink is of great value as part of an

athletes diet.

Approach of Experiment:Using appropriate tests to compare the amounts of reducing sugar, protein, & starch found in

two sports drinks.

Variables to be kept constant:Volume of Test Solutions, Concentration of Test Solutions, Temperature, Humidity, Duration

the 2 samples were left in the boiling water bath for Benedicts Test, etc.

Variable(s) to be measured:Color change and formation of precipitate in Benedicts Test, Presence of lilac color in Biuret

Test, Color change in Starch Test, Presence of white precipitate and heat evolved in Emulsion

Test.

List of Apparatus and Materials needed:1. 6 Test tubes

2. 2 Beakers (250 ml & 500 ml)

3. 2 Syringes (6 ml)

4. 1 Markers

5. 1 Test tube rack

6. 1 Test-tube holder

7. 1 Test-tube brush8. 1 Benedicts solution

9. 1 Sodium Hydroxide solution

10. 1 Copper Sulphate solution

11. 1 Iodine solution

12. 2 Health Drink samples (labeled as solutions A & B)

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Procedures:Test for Reducing Sugar

1) Add 2 cm of Benedicts Solution to 2 cm of Sample A & B in a test tube with syringe.

2) Shake the mixture and heat it by placing the test-tube into a boiling water bath for5minutes.

3) Observe the colour changes in the mixture after 5 minutes.

Test for Starch

1) Use the dropper to add 2 drops of iodine solution to 2 cm of Sample A & B with syringe

and shake.

2) Observe the colour changes.

Test for Proteins

1) Add 2 cm ofSodium Hydroxide Solution (NaOH) to 2 cm of Sample A & B in a test

tube with syringe.

2) Shake the mixture gently to mix well.

3) Add the 1% copper sulphate solution (CuSO) to the test tube, drop by drop, shaking

gently after every drop, to the mixture.

4) Observe the colour changes.

Results:

Observations Conclusions

Health Drink A B A B

Benedict's Test Large amountof orangeprecipitate wasformed.

Large amountof orangeprecipitate wasformed.

Reducing Sugaris present.

Reducing Sugaris present.

Iodine Test A blue-blackcolour wasobserved

The browncolour ofiodine solutionremained.

Starch ispresent.

Starch is absent.

Biuret Test The mixture inthe test tubeturned from lightblue to lilac incolour

The mixtureremained lightblue in colour

Protein ispresent.

Protein isabsent.