Biology presentationBiology presentation
Chan Siu HongChan Siu Hong (24(24))
Lam Kwan ChekLam Kwan Chek (27(27))
Lee Nok HimLee Nok Him (30(30))
Lo HallLo Hall (34(34))
Wong Tsz KiWong Tsz Ki (42(42))
Group Group 8:8:
IntroductionIntroduction
Our group have bought a can of condeOur group have bought a can of condensed milk (nsed milk ( 煉奶煉奶 ) to test for the presenc) to test for the presence of glucose, reducing sugar, starch, fate of glucose, reducing sugar, starch, fats, proteins and vitamin C by different fos, proteins and vitamin C by different food tests.od tests.
PreparationPreparation We opened the can of condensed We opened the can of condensed milk and pour the contents into a milk and pour the contents into a beaker until the beaker is 50mL full. beaker until the beaker is 50mL full. Then add some water to dilute the Then add some water to dilute the milk. The condensed milk used in the milk. The condensed milk used in the tests are taken from here by using tests are taken from here by using dropper.dropper.
PreparationPreparation
Materials preparedMaterials prepared
1 bottle of distilled water1 bottle of distilled water
2 Clinistix papers2 Clinistix papers2 Albustix papers2 Albustix papers2 droppers2 droppers2 filter papers2 filter papers
1 tube of cooking oil1 tube of cooking oil1 bottle of iodine solution1 bottle of iodine solution1 boiling water bath1 boiling water bath1 bottle of DCPIP solution1 bottle of DCPIP solution1 spot plate1 spot plate1 bottle of Benedict’s solution1 bottle of Benedict’s solution1 beaker1 beaker
1 can of condensed milk1 can of condensed milk1 test tube rank1 test tube rank
10 test tubes10 test tubes
Tests orderTests orderTest for glucoseTest for glucose
Test for reducing sugarsTest for reducing sugars
Test for fatsTest for fats
Test for starchTest for starch
Test for vitamin CTest for vitamin C
Test for proteinsTest for proteins
1. Transfer a drop of condensed milk 1. Transfer a drop of condensed milk to the well of a spot plate. Also to the well of a spot plate. Also add another drop of distilled add another drop of distilled
water water to another well of the spot to another well of the spot plate, plate, which is used as a control. which is used as a control.
Steps:Steps:
First Test: Test for glucoseFirst Test: Test for glucose
2. Dip the test end of a Clinistix 2. Dip the test end of a Clinistix paper into the sample and paper into the sample and observe any colour change.observe any colour change.
Steps:Steps:
First Test: Test for glucoseFirst Test: Test for glucose
The colour changed from The colour changed from yellowyellow to to light light greengreen..
First Test: Test for glucoseFirst Test: Test for glucose
Result:Result:
After test for water (Original colour)
After test for condensed milk
Second Test: Test for reducing Second Test: Test for reducing sugarssugars
1. Mix equal volumes of condensed 1. Mix equal volumes of condensed milk and Benedict’s solution in a milk and Benedict’s solution in a test tube. Also prepare another test tube. Also prepare another test tube contains mixture oftest tube contains mixture of
distilled water distilled water and Benedict’sand Benedict’s
solution.solution.
Steps:Steps:
mixture of distilled water and Benedict’s solutionmixture of distilled water and Benedict’s solution
mixture of condensed milk and Benedict’s solution
Second Test: Test for reducing Second Test: Test for reducing sugarssugars
2. Put the test tubes into a boiling 2. Put the test tubes into a boiling water bath. Boil the mixture for 5 water bath. Boil the mixture for 5 minutes and observe any change minutes and observe any change in in the mixture.the mixture.
Steps:Steps:
Second Test: Test for reducing Second Test: Test for reducing sugarssugars
3. Stand the test 3. Stand the test tubes in a tubes in a
test test tube rank for tube rank for 15 minutes.15 minutes.
Steps:Steps:
Second Test: Test for reducing Second Test: Test for reducing sugarssugars
The colour changed from The colour changed from light light blueblue to to orangeorange..
Result:Result:
Mixture of distilled water and Benedict’s solution (Original colour)
Mixture of condensed milk and Benedict’s solution
Third Test: Test for fatsThird Test: Test for fats
1. Transfer a drop of condensed milk 1. Transfer a drop of condensed milk to a filter paper and another drop to a filter paper and another drop of distilled water. Let the two of distilled water. Let the two
papers dry in papers dry in the air for 5 the air for 5 minutes.minutes.
Steps:Steps:
Third Test: Test for fatsThird Test: Test for fats
2. Put the two papers under the light. 2. Put the two papers under the light. Observe any translucent spot.Observe any translucent spot.
Steps:Steps:
The condensed milk spot becomes tranThe condensed milk spot becomes translucent.slucent.
Result:Result:
Third Test: Test for fatsThird Test: Test for fats
Cooking oil spot (translucent)
Condensed milk spot (translucent)
Fourth Test: Test for starchFourth Test: Test for starch
1. Transfer a drop of condensed milk 1. Transfer a drop of condensed milk to the well of a spot plate. Also to the well of a spot plate. Also transfer a drop of distilled transfer a drop of distilled water water
to to another well of the spot plate.another well of the spot plate.
Steps:Steps:
Fourth Test: Test for starchFourth Test: Test for starch
2. Add a drop of iodine solution to 2. Add a drop of iodine solution to the sample and observe any colour the sample and observe any colour
change.change.
Steps:Steps:
There is no visible change.There is no visible change.Result:Result:
Fourth Test: Test for starchFourth Test: Test for starch
Condensed milk with iodine solution
Distilled water with iodine solution
Fifth Test: Test for vitamin CFifth Test: Test for vitamin C
1. Add a few drops of DCPIP solution 1. Add a few drops of DCPIP solution in two test tubes.in two test tubes.
Steps:Steps:
Fifth Test: Test for vitamin CFifth Test: Test for vitamin C
2. Add in same amount of condensed 2. Add in same amount of condensed milk. Stir them well then. Also milk. Stir them well then. Also
add add another tube of distilled water.another tube of distilled water.
Steps:Steps:
Fifth Test: Test for vitamin CFifth Test: Test for vitamin C
3. Put the test tubes3. Put the test tubes in a boiling in a boiling water bath for 5 minutes. Then water bath for 5 minutes. Then put them into a beaker of cool put them into a beaker of cool water.water.
Steps:Steps:
The solution change from blue into The solution change from blue into light blue.light blue.
Result:Result:
Fifth Test: Test for vitamin CFifth Test: Test for vitamin C
Condensed milk solution
1. Transfer a drop of condensed milk 1. Transfer a drop of condensed milk to the well of a spot plate. Also to the well of a spot plate. Also add distilled water to another add distilled water to another
well well of the spot plateof the spot plate
Steps:Steps:
Sixth Test: Test for proteinsSixth Test: Test for proteins
2. Dip the test of an Albustix paper 2. Dip the test of an Albustix paper into the sample and observe any into the sample and observe any colour change.colour change.
Steps:Steps:
Sixth Test: Test for proteinsSixth Test: Test for proteins
The Albustix paper turns from The Albustix paper turns from yellowyellow to to light greenlight green..
Result:Result:
Sixth Test: Test for proteinsSixth Test: Test for proteins
After test for condensed milk
After test for distilled water (Original colour)
ConclusionConclusion
TestTest Original colourOriginal colour Final colourFinal colour MeaningMeaning
Clinistix paperClinistix paper YellowYellow Light greenLight green [[]Glucose]Glucose
Benedict’s testBenedict’s test Light blueLight blue OrangeOrange [[]Reducing sugar]Reducing sugar
Grease spot testGrease spot test TranslucentTranslucent [[]Oil]Oil
Iodine testIodine test BrownBrown BrownBrown [[]Starch]Starch
DCPIP testDCPIP test BlueBlue Light blueLight blue [[]Vitamin C]Vitamin C
Albustix paperAlbustix paper YellowYellow Light greenLight green [[]proteins]proteins
Thanks for watching!! Goodbye…
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