Food decay and disease

MATERIALS NEEDED:

• Approximately 20 grapes,
• 4 ziplock bags,
• 500ml to 1L of water,
• Kettle.

PROCEDURE

• I prepared the ziplock bags and put 5 grapes in each.
• I put a label on each bag so they weren't misplaced.
• Then I boiled the water to make sure it wasn't contaminated.
• I put two bags in the fridge and 2 on a table at room temperature.

SAFETY

• Face mask, in case the bags are brought near the face.
• I made sure that nobody ate them.
• They were in safe conditions and had labels on the bags.
• I made sure not to spill water, and to dispose of the waste properly.

Controls:

• The water will be boiled and cooled to make sure there are no germs.
• The ziplock bags will all be the same size and will all be kept in for the same duration of time.
• The ziplock bags are open.
• The grapes will be checked using a microscope to identify the diseases properly.

Conditions

Prediction:
My prediction is that the grapes in warmer and more moist conditions will catch diseases quicker and have a more significant effect on the appearance of the grapes.

Hypothesis:
I'm expecting the grapes in more hot and humid conditions will pick up types of fungal diseases which induces rot because in hot and humid conditions, disease travels easier.
I'm going to see what diseases occur in which conditions.

Common grape diseases

• Grape Black Rot
• Downy Mildew
• Pierce's Disease
• Botrytis Bunch Rot

Black Rot is a type of fungus that attacks grape vines during hot and humid weather.

Botrytis Bunch Rot is where grapes split, collapse and appear to have a fuzzy white material on them.

Downy Mildew is another fungus that attacks grapes, it doesn't directly attack the fruit but it attacks the
leaves.

Pierce's Disease is a bacteria, it multiplies in a plant and blocks the movement of water in the plant.

Data

Bag 1 RESULTS - [REF, WATER]

• May 6th: No change.
• May 7th: No change.
• May 8th: Signs of Black Rot Disease.
• May 9th: Increased signs of Black Rot Disease.
• May 10th: Increasing signs of Black Rot Disease.
• May 12th: Most signs of Black Rot Disease were shown.
• May 13th: Similar state to previous day.
• May 14th: Nearly all signs of Black Rot Disease

Bag 2 RESULTS - [REF, NO WATER]

• May 6th: No change.
• May 7th: No change.
• May 8th: No change.
• May 9th: Small signs of Black Rot Disease.
• May 10th: Increasing signs of Black Rot Disease.
• May 11th: Similar state to previous day.
• May 12th: A small change from previous state.
• May 13th: Darkening colours near the top of the grapes.
• May 14th: Some but not many signs of Black Rot Disease.

BAG 3 RESULTS - [ROOM TEMP, WATER]

• May 6th: No change.
• May 7th: No change.
• May 8th: Beginning signs of Botrytis Bunch Rot.
• May 9th: Heightening signs of Botrytis Bunch Rot.
• May 10th: Increasing signs of Botrytis Bunch Rot.
• May 11th: Small increasing symptoms.
• May 12th: Similar state to previous day.
• May 13th: Similar state to previous day.
• May 14th: Many signs of Botrytis Bunch Rot.

BAG 4 RESULTS - [ROOM TEMP, NO WATER]

• May 6th: No change.
• May 7th: No change.
• May 8th: Insignifigant signs of Black Rot Disease.
• May 9th: Visible signs of Black Rot Disease.
• May 10th: Increasing signs of Black Rot Disease.
• May 11th: Small changes in colour.
• May 12th: Colours darkening.
• May 13th: Many signs of Black Rot Disease
• May 14th: Nearly all signs of Black Rot Disease.

Conclusion

• Bag 1 grapes were developing Black Rot but not as fast as the others.
• Bag 2 was developing Black Rot very slowly.
• Bag 3 was developing Botrytis Bunch Rot rapidly.
• Bag 4 was developing Black Rot rapidly.

RESULTS

A grape with Black Rot would not be considered edible and farmers would throw these away, they also contaminate the air and can be dangerous to breathe in.

A grape with botrytis is aswell not considered edible as it is a dangerous mold that attacks grapes, these also contaminate the air and can be dangerous to inhale.

REFLECTION

If I were to do another CBA I'd try different conditions for the grapes or use a different fruit.

By
Erik
W
2L