Hypothesis:

 

I think that the banana in the plastic bag will ripen the fastest because the Ethylene gas that the banana releases as it ripens will be trapped with the banana, causing it to ripen faster. I think that the banana with the plastic wrap on the stem will ripen the slowest because it slows down the banana releasing ethylene gas.

 

• Bananas are the most traded fruit in the world. 
• Banana plants are actually herbs which can grow up to 15 meters tall.
• Bananas are grown where the average rainfall is between 198 and 248 cm and the average temperature is 27 degrees celsius.
• It takes a banana plant 9 to 12 months to grow a banana. 105 million tons of bananas are produced each year and are grown in more than 150 countries, Including India, China, Indonesia, Nigeria, Brazil, Ecuador, Philippines, and Guatemala.

 

• Ethylene Gas is pumped into banana ripening rooms.

• Ethylene gas is colourless and flammable and is a hydrocarbon gas. It is the most commercially produced organic compound in the world. 

• Ethylene gas is used in manufacturing plastics, rubber, paint, detergents, and toys. 
• Ethylene gas is in the atmosphere because it is a byproduct of partial combustion of organic fuels (it comes from car exhaust, volcanic eruptions, and forest fires.)
• Concentrations of ethylene gas greater than 1000 parts per million can cause dizziness.

• The molecular compound of ethylene is C2H4.

Variables:

 

Independent: The environment the bananas are in.

Dependant: How much each banana ripened.

Controlled: 

• Using the same fruit
• Bought at the same time
• Starting amount of ripeness
• In the same room
• Same length of time

Materials:

 

• 12 Bananas
• 3 Ziploc Plastic Bags
• Plastic Wrap
• Paper
• Yarn
• Logbook
• Scale 

 

Procedure:

 

1. Buy a bunch of 12 bananas and label them.

 

2. Take pictures of what the bananas look like and weigh the bananas.

 

3. Put 3 bananas in separate Ziploc plastic bags.

 

4. Wrap the stems of 3 separate bananas in plastic wrap. Make sure the stems are fully covered.

 

5. Put 3 bananas in the fridge.

 

6. Leave the last 3 bananas with nothing done to them.

 

7. Space out the bananas with the plastic wrapped stems, plastic bag, and control bananas on the same table.

 

8. Take a picture of what the bananas look like every day and write down observations.

 

9. Once the experiment is over, weigh the bananas again.

 

Starting My Experiment

 

Jan. 27th, 2025

 

Banana 3 in each environment is from a different bunch than 1 or 2

 

I tried to have the sizes of the bananas in each environment different.

 

Banana Weight in grams:

 

 

Weights are with labels, without plastic bags/wrap

 

There is a small amount of air in each plastic bag.

 

Fridge 1, plastic wrap 3, control 3, and plastic bag 2 all had banana stickers.

 

Observations:

 

Jan.28th, 2025

 

All of the bananas are slightly more yellow. The ones in the fridge are the most green,then the ones in the plastic bags, and the plastic wrap ones and the control ones are the same. There is condensation in the plastic bags.

 

Jan.29th, 2025

 

Plastic wrap bananas are very yellow except for the stems, which are green. There is more condensation in the plastic bags, especially plastic bag 2. The plastic bag bananas are about the same as yesterday. The control bananas are also very yellow and look similar to the plastic wrap ones, except the stems are less green. The bananas in the fridge are still green and are very hard. There are some scratches on plastic bag banana 2 from where I took the sticker off, and those have now turned brown.

 

Jan.30th, 2025

 

I flipped over the bananas so I could see the other side. The other side of the plastic wrap and control bananas are mostly the same, the other side of plastic bag banana 3 has turned brown in one spot. There is something white and sticky on the stem of control banana 3 and it looks like the condensation inside the plastic bags. The stem of control banana 3 has also turned brown. The fridge bananas are still green, but have lots of brown spots on them.

 

Jan.31st, 2025

 

The plastic wrap and control bananas are more yellow and the plastic bag bananas are still green, and are slowly turning yellow.The fridge bananas are green but are turning black.

 

Feb.1st, 2025

 

all of the bananas have started to turn brown. There are some brown dots on the plastic wrap and control bananas. The plastic bag bananas are green and yellow, only plastic bag banana 3 has a lot of brown.The fridge bananas are almost entirely covered in black, with some green. There is still condensation in the plastic bags.

 

Feb.2nd, 2025

 

There are more brown dots on the plastic wrap and control bananas. The plastic bag bananas are more yellow, and there is more condensation in the bags. The brown spot on plastic bag banana 3 is bigger. The fridge bananas are more black than yesterday.

 

Feb. 3rd, 2025

 

 I flipped over the bananas again today. There are lots of brown dots on the plastic wrap and control bananas. There is still condensation in the plastic bags. The plastic bag bananas are mostly yellow, with a bit of green around the edges.the brown spot on plastic bag banana 3 is the same. The fridge bananas look even more black.

 

Feb. 4th, 2025

 

The plastic wrap and control bananas are more brown and have started to smell. The plastic bag bananas are mostly the same as yesterday and there is condensation in the bag. The condensation is mostly near the stem and scratches or brown spots on the banana. The fridge bananas are still turning black.

 

Feb. 5th, 2025

 

There are more brown spots on the plastic wrap and control bananas. There is more condensation in the plastic bags, and the bananas are slightly more yellow. The fridge bananas are slightly darker than yesterday.

 

Feb. 6th, 2025

 

The plastic wrap and control bananas have turned more brown. The plastic bag bananas are slightly more yellow and there is condensation in the bags. The fridge bananas are still getting darker.

 

Feb. 7th, 2025

 

The plastic wrap bananas are more brown, the control bananas are the same as the plastic wrap ones, except the control banana stems have turned brown and are a lot smaller than before. I can’t see the stems of the plastic wrap bananas because they are covered in plastic wrap. The plastic bag banana 2 has a small grey-brown dot on it, and plastic bag banana 1 has some small grey-brown spots. There is more condensation in the plastic bags. The fridge bananas are slightly darker than yesterday, but mostly the same.

 

Feb. 8th, 2025

 

The plastic wrap bananas are mostly the same as yesterday, but a little more ripe. The plastic bag bananas are slightly more yellow than yesterday. There is condensation in the plastic bags. The control bananas are the same as the plastic wrap ones. The fridge bananas are more black than yesterday.

 

Feb. 9th, 2025

 

The plastic wrap bananas are more ripe than yesterday. The plastic bag bananas are mostly the same as yesterday, except there is more condensation in the plastic bags. Also, the plastic bags have started to curl. The control bananas are also more ripe than yesterday, and the only difference that I have noticed between the plastic wrap and control bananas is that the stems of the control bananas are very small and have turned brown, but the plastic wrap bananas stems are still yellow and the same width as when I started the experiment. The fridge bananas are still black.

 

Feb. 10th, 2025

 

Today is the last day of my experiment, so I took the plastic wrap off of the banana stems. Plastic bag banana 1’s stem has turned brown at the top, but the bottom is still yellow. Also, it is a lot thicker than the stems of the control bananas.the stem of plastic wrap banana 2 is bigger than the other stems because it was the top part of the banana bunch. There is some fuzzy white mold on the stem, and some black residue on the plastic wrap. There is also some mold on the stem of plastic wrap banana 3 and it is the same type of mold as the mold on plastic wrap banana 2. The stem is black on one side, but yellow on the other. When I opened plastic bag 1, it smelled like bananas. The plastic bag banana 1 is mostly still healthy and mostly yellow, with a little bit of green, except for the bottom, which has a tiny bit of the same type of mold as the plastic wrap bananas. Plastic bag 2 also smelled like bananas. Plastic bag banana 2 is also yellow with some green, and like plastic bag banana 1, there is some mold on the bottom. Plastic bag 3 also smelled like bananas. The brown spot on plastic bag banana 3 is not very dark, and there are tiny white dots of mold on it.there is also mold on the stem and bottom of the banana. There is no mold on the control bananas, and they are all brown and yellow. The fridge bananas are entirely black, and there is no mold, except for some tiny white dots on the stem of fridge banana 2.

 

Ending My Experiment

 

Banana weights after experiment in grams:

 

 

Banana insides:

 

Control banana inside looks ripe and ready to use

 

Plastic wrap bananas inside also looks ripe and ready to use

 

Plastic bag banana skin was thicker and there are little holes in the skin. Inside looks ripe and ready to use.

 

Fridge banana skin was black and it was very obvious where the skin ended and banana started. Inside looks ripe and ready to use.

 

The fridge bananas went from bright green to black, without turning yellow. The plastic wrapped stem bananas ripened at almost the same time as the control bananas and the stems had little white dots of mold. The plastic bag bananas took the longest to ripen, and there were some very tiny dots of white mold on the bottom, the same type of mold as before. When comparing the weight of the bananas before and after the experiment. The control bananas lost an average of 40.3 grams, the plastic wrapped stem bananas lost an average of 37.3 grams, the plastic bag bananas lost an average of 3.7 grams, and the fridge bananas lost an average of 16 grams.

 

The fridge bananas were damaged by the cold temperatures of the fridge, which was kept at 3.3 degrees celsius or 38 degrees fahrenheit, this caused the bananas to turn black. The plastic bag bananas where the least ripe, probably because there was no ethylene gas from other bananas around it.the plastic wrap bananas ripened at the same speed as the control bananas, I think this is because ethylene gas comes from the whole banana, not just the stem.

 

• Some bananas may have had unnoticed bruises or peel blemishes.

 

• The bananas were slightly different sizes.

 

• The bananas may have had slightly different amounts of sunlight.

 

• Some bananas may have started more or less green than others.

https://pmc.ncbi.nlm.nih.gov/articles/PMC6521425/#sec1 

 

bananalink.org.uk/all-about-bananas/#:~:text=Bananas%20do%20not%20grow%20from,are%20avalible%20all%20year%20round. 

 

worldostats.com?/banana-production-by-country-2024/      

 

postharvest.com/blog/what-is-ethylene-gas-how-it-affects-fruits-and-vegetables

 

bmcbiol.biomedcentral.com/articles/10.1186/s12915-016-0230-0#:~:text=The%20simple%20hydrocarbon%20ethylene%20(C,major%20hormone%20in%20plant%20biology 

 

I would like to acknowledge my Mom and Dad for buying the supplies and printing the banana photos.