8/11/2019 Fruits and Browning

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8/11/2019 Fruits and Browning

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Procedure

1. Prepare 100ml of the 6 solutions: a 1.0% solution and a 0.1% solution of each

of the 3 substances.

2. Cut the apple into equally size for 8 portions.

3. Place an untreated apple slice on a petri dish and label it Control.

4. Using tongs, dip another apple slice into one of the test solution for 30

seconds, place it on the petri dish and label it with the name of the solution.

5. Rinse the tongs and repeat the same procedure for the other 5 solutions.

6. Soak one apple slice in water for 30 seconds. Place it on a petri dish and label

it Water Soak.

7. Observe the slices every 10 minutes for one hour and record your

observations.

8.

Evaluate the colour change on a scale of 0 to 5, 0- being no colour changeand 5 being the highest grade of brown.

9. Repeat step 2 to step 7 by changing the type of fruits.

10.Record all data in a table.

Results

Level of browning

No Treament

10

min

20

min

30

min

40

min

50

min

60

min

70

min

80

min

90

min

1 No treatment (control)

2 1% ascorbic acid

3 1% citric acid

4 1% acetic acid

5 1% sodium sulphite NaSO3

6 0.1% ascorbic acid

7 0.1% citric acid

8 0.1% acetic acid

9 0.1% sodium sulphite

NaSO3

10 Water soak

Colour scale

5 = completely dark brown

4 = fully covered light brown

3 = half-covered light brown

2 = some brown patches

1 = no browning present