SIP Experiment - FINAL

I conducted the experiment, the final one! I improved on the way I conducted the experiment using the tips given by Ms Tan. Here are the results, the pictures speak for themselves:

Control slice

After 10 minutes

After 20 minutes

After 30 minutes

After 40 minutes

After 50 minutes

After 1 hour

After 1 hour 10 min

After 1 hour 20 min

After 1 hour 30 min

After 1 hour 40 min

After 1 hour 50 min

After 2 hours

Set-up of experiment

Consultation with Ms Tan

Yesterday, I had a consultation session with Ms Tan, my Science teacher. It was a most fruitful session, and I picked up many tips about how to improve my experiment!

Experiment

1. My control should be the one in tap water, and not the one exposed to air since all the other peaches were immersed in a kind of liquid.

2. It is better to record the appearance of the peaches at regular intervals e.g. after every 10 min, instead of my earlier design, which was to record their appearances at 5 minute intervals for half an  hour (6 times), then at 15 minute intervals for the next 1 hour (4 times), then at 30 minute intervals for the next 2 hours (4 times).


3. When I take pictures, the curtains must be closed and only artificial light should be used to regulate the amount of light the peaches are exposed to so that the pictures of the colour of the peaches will be accurate.


4. I need to use photoshop to record their HSB values (Hue, Saturation, Brightness). This can be obtained by using a colour picker to pick a specific spot on the peaches.


5. The second part of the experiment is no longer necessary.


Anyway, here are the pictures of Part 2 since I have already conducted the experiment!

Experimental set-up

Control slice (bad photographic skills)

Peaches taken out after 15 minutes of soaking

SIP Tentative Methodology (Part 2)

Materials needed:

• 3 plastic transparent cups
• 10 small paper plates
• 3 plastic spoons
• Marker
• Juice extractor
• Knife
• Stopwatch 
• Measuring Cylinder

Materials for liquids:

• 100 ml Tap Water + 1 teaspoon of salt
• 2 Lemons
• 3 Limes
• 1 peach (cut into 10 equal slices)

Method:

1. Label all plates and cups with a marker. Arrange everything on the table, such that there are 3 rows of 3 sets of plates

2. Squeeze the fruits using the juice extractor and pour the juice into the cups. Prepare the salt water.

3. Cut the peaches into 10 equal slices. Drop 3 slices into each liquid, making sure all 3 slices are fully submerged in the respective liquids. Place the final slice on the control plate.

4. Start the stopwatch immediately when all the peach slices are in the liquid. 
5. After 5 minutes is up, take one peach slice from each cup and place it on the first row of plates.   
6. Observe each peach slice for the first sign of browning and record the time this occurred.
7. At the same time, continue timing with the stopwatch. Repeat steps 5 and 6, but this time take the peaches out 10 and 15 minutes after the start of the experiment. Place the peaches on the second row and third row of plates respectively.

SIP Experiment Part 2

I decided to do an extension of the previous experiment to find out what is the least amount of time that the peaches have to be soaked in Vitamin C before they can retain their colour when placed outside. (this was taken from one of my previous posts) The reason why I wanted to do this experiment is because it is more practical: most people would not soak their peaches for that long before eating them. Soaking the peaches for so long would alter their taste as well. 


From the previous experiment: After soaking for 9 hours, lemon juice and lime juice were the clear winners.  I decided to test these juices for this new experiment. I also decided to test salt water (1 teaspoon) because it is the most cost-effective. 


In my next post I shall once again do a rough methodology for this extension experiment.

SIP Experiment Results

Continuing from the previous post, after 9 hours I took all the peach slices out and put them on the paper plates. I threw away the control and the peach in tap water because their it was obvious they were not effective.

After 9 hours of soaking

I ended up leaving the rest of the peaches overnight! I put a cover over them to prevent flies/lizards from interfering with the results of the experiment.

I woke up at 2.45 am to check on the peaches. (Actually no, I woke up to catch the rare total lunar eclipse and went to check on the peaches after that)

Here are the results after 6 hours of the peaches being taken out of the liquids in order of merit, starting from the least brown to the most brown:

Lemon Juice - Unchanged (Not brown at all)
Redoxon 1000
Lime Juice
Orange Juice (slight brown)
Redoxon 500 (totally brown)
Kiwi Juice (totally brown)

At 8.30 am the next morning, I recorded down their appearances again:

Lemon Juice (still the best)
Redoxon 1000
Lime Juice
Orange Juice (slight brown)
Salt water (1/2)
Salt water (1)
Redoxon 500
Kiwi Juice

8.30 am (about 12 hours after peaches were taken out)

The last 4 were completely brown. However, I had forgotten to note down the appearances of the 2 peaches placed in the salt water at 2.45 am! But judging from the rest of the peaches, things had not changed much 6 hours later.

SIP Experiment Trial 2

 The tentative methodology really helped! I was a lot more organised then, so the experiment was a success. Here are some of my observations:

1. Trial 1 actually helped in this experiment, because I was better at taking the peaches out of the cups and was able to record their appearances faster. This minimised the time the peaches were exposed to air.

2. The peaches in the juices appeared slightly discoloured, but this was because of the colour of the juice which stained the peaches.

3. Naturally, I took many pictures, but had to make sure my shadow (or the camera's) did not get in the way of the experiment. Later, I also had to make sure the lighting of the set-up was the same, or the peaches may look lighter or darker than they actually were during the experiment.

I also made some modifications to the methodology. Instead of observing them every 5 minutes, I observed them at 5 minute intervals for the half hour (6 times), then at 15 minute intervals for the next 1 hour (4 times), then at 30 minute intervals for the next 2 hours (4 times). I did this because I realised that in the 1st experiment, after around 30 minutes the rate of browning of the peaches slowed down. Thus, it would be all right to observe them at progressively longer intervals.

After 3 1/2 hours, the control was so brown it looked more like a potato wedge covered in dark gravy. The peach in tap water did not fair too well either, being only slightly less brown than the control. (of course I will use more precise terms in my report!) But all the peaches in the Vitamin C remained perfectly unchanged, since the start of the experiment! They were still a brilliant yellowish-white. This really surprised me, for I had not thought that Vitamin C could be such a wonderful preservative! I expected them to be slightly brown, but not as brown as the tap water or salt water.

I decided to leave the peaches in the cups to observe them after 5 1/2 hours and after 9 hours since the start of the experiment. At the 9 hour mark, I took the peaches out of the cups and left them on the plates, then observed them to see if they would turn brown after being exposed to air and having been soaked in their respective liquids for 9 hours. 1 hour after I did so there was no change in appearance in all the peaches!

This is very interesting. The peaches in Vitamin C had not changed their colour since the start of the experiment. After 9 hours of soaking, when taken out, they did not change their colour even after being exposed to air. Hmm...I wonder what is the least amount of time that the peaches have to be soaked in Vitamin C before they can retain their colour when placed outside? After all, most people would not soak their peaches for 9 hours before eating them!

~~~

Experimental materials: fruits + redoxon + salt



Experimental materials 2: fruit juices + juice extractor



Experimental set-up

Peaches taken out after 5 minutes

Peaches taken out after 30 minutes

After 1 hour

After 3 hours

SIP Tentative Methodology

Materials needed:

• 10 plastic transparent cups
• 10 small paper plates
• 9 plastic spoons
• Marker
• Juice extractor
• Knife
• Stopwatch 
• Measuring Cylinder

Liquids Tested:

• 100 ml Tap Water
• 100 ml Tap Water + 1 teaspoon of salt
• 100 ml Tap Water + 1/2 teaspoon of salt
• 2 Lemons
• 2 Oranges
• 3 Limes
• 2 Kiwis
• Redoxon (1 tablet)
• Redoxon (1/2 tablet)
• 1 peach

Method:

1. Label all plates and cups with a marker. Arrange everything on the table.

2. Squeeze the fruits using the juice extractor and pour the juice into the cups. 

3. Measure 100 ml of water from the measuring cylinder and pour into the respective cups (tap water, salt water and redoxon). Put the redoxon tablets in gently, making sure not to make the water in the cups spill out excessively.

4. Cut the peaches quickly, and once 10 peach slices are obtained, drop the peaches in carefully into the cups. Put one peach slice  on the control plate.

5. As soon as slices are put in, start timing with the stopwatch immediately.

6. Take the peaches out at 5 minute intervals and place them on the plates. Record their appearance, then quickly put them in the cups again.

7. Repeat step 6 for about one hour.

SIP Trial Improvement and Insights

So things to work and improve on:

• Be more prepared! I should have thought through the experiment a bit more carefully. I think writing out a rough methodology and the list of materials needed would be useful so that my thoughts are more organised. 

And to solve the earlier problems:

1.  Label everything beforehand with a marker.
2. Cut the peaches as fast as possible so that they will not brown so quickly.
3. I think using spoons instead of chopsticks would work better to take the peaches out to prevent them from disintegrating. 
4. To solve the problem of putting them in all at once, I will rope in the help of my family members.

I hope the next experiment will work better!

SIP Experiment Trial 1

I decided to go ahead with my experiment yesterday! After buying the necessary materials, I was all ready to start. All I can say is that I only wish I had done more thinking before starting because the experiment was a total failure!

- The first thing I did was to get 10 transparent plastic cups and 10 small paper plates to put the peach slices and different liquids in. I decided to use two fruits for each type of fruit because I highly suspected the tiny lime may not contain enough juice to submerge the peach slice. But I overlooked one problem: the fact that at first slice of the knife, some juice squirted out. This was an especially big problem for the limes because every drop of juice could not be wasted. Thus in the end, I used 3 limes to make up for the wastage.

- I then laid everything out nicely onto the table before getting ready to cut the peaches. However, as soon as I had cut the peaches and was all ready to put the peaches into the cups, I realised I had forgotten to label all the cups and plates! Frantically, I began labeling them, but by the time I had finished the peaches were already turning brown!

- I decided to just continue with the experiment to see if I would encounter any more problems, even though I knew I would have to conduct the experiment again because the peaches were brown. So I took the peaches out at regular 5 minute intervals and placed them on the plates to see how brown the peaches were. (see pictures below)

There were a few problems with this:

1. I used chopsticks to take the peaches out, but the peaches were quite slippery and every time I took them out they seemed to disintegrate a little.

2. It was difficult to take them out all at once once the 5 minute interval was reached. The same problem was encountered at the starting to place all the peaches into the cups at the same time.

~~~



Peaches in cups

Peaches taken out after 5 minutes



Peaches taken out after 10 minutes

~~~

 So I encountered quite a number of problems in this try. In my next post I shall state what I should improve on to make the experiment more successful :)

SIP Materials + Research

After doing much research, I decided to test a few commonly available household products to see which of these can prevent the browning of the peaches the best. The products I tested are:

1. Tap Water
2. Salt Water (1 teaspoon of salt)
3. Salt Water (1/2 teaspoon of salt, to see if the concentration of salt affects the amount of browning of the peaches)
4. Lemon Juice
5. Orange Juice
6. Lime Juice
7. Kiwi Juice
8. Redoxon (1 tablet)
9. Redoxon (1/2 tablet)

And of course, a control which was exposed to air so that a fair comparison could be made.

I do think that the concentration of Vitamin C in products 4 - 9 affects how well they can prevent browning, so I did more research to find out the concentration of Vitamin C in each of the products. Here is the list (per fruit) :

1. Lemon (46 mg)
2. Orange (53 mg)
3. Lime (29 mg)
4. Kiwi (98 mg)
5. Redoxon tablet (1000 mg)
6. Redoxon 1/2 tablet (500 mg)

* Vitamin C content figures given are approximate, may vary between different varieties of the same fruit or even between separate fruits of the same variety. The ones listed here are taken from http://www.naturalhub.com/natural_food_guide_fruit_vitamin_c.htm

Change of Idea

After consultation with Ms Tan, my original idea did not seem like such a good one after all!

Firstly, there were too many factors affecting my results. I had intended on testing out the experiment on 3 cars, but Ms Tan had rightly pointed out that the 3 cars were of different make, model etc. She suggested I go to a car dealer and ask if I could test the experiment out on their cars (since they were all already parked outside and were all of the same brand), but this was not very good as the salesperson would not agree to the experiment.

Secondly, if it was a rainy day they whole experiment was going to be a failure. Since I can borrow the necessary experiment from the the science laboratory for only 3 days, if all 3 days were rainy ones I could not even conduct my experiment!

Thus, I decided to change my idea. My favourite fruit is peach, and every time I ate peaches I noticed that they would turn brown after a while. This made the peach unappetizing. I was wondering whether there were any easily available household preservatives that could preserve the colour of the peaches for the longest time?

SIP Proposal (Appendix D)

APPENDIX D

Science Investigative Project

Project Proposal Form

Name:

Claire Tay Ern Ying  (6)

Sec 2/13

Topic of investigation  :

Oxidation of peaches

A     Observations made
I noticed that every time I ate peaches, the peaches tended to turn brown very quickly. I heard that salt water was an effective method of retaining the colour of the peaches, and I wanted to test if this was true. I also wondered if there were any other commonly available household substances that could retain the colour of the peaches. 


Based on background knowledge, I also know that Vitamin C is a good preservative.


B   Research Question
What is the best household preservative to prevent the browning of cut peaches?


C     Hypothesis
Redoxon (1000 mg) is the best household preservative to prevent the browning of cut peaches as it contains a high concentration of Vitamin C.


D     A short summary of research done on the area of investigation

Peaches contain an enzyme (called polyphenol oxidase or tyrosinase) that reacts with oxygen and iron-containing phenols that are also found in the peach. The browning appears when the fruit is cut or bruised because these actions damage the cells in the fruit, allowing oxygen in the air to react with the enzyme and other chemicals.

E     Bibliography

http://recipes.howstuffworks.com/question168.htm

Writing Guidelines

Science Investigative

Project Report Writing Guidelines

1. What do you want to find out? (Aim/Purpose/Research question)

2. What is the tentative explanation of your research question? (Hypothesis)

3. In an investigation, there is only one variable to be changed.

Which variable will you change in this investigation? (Independent Variable)(Aim/Purpose/Research question)

2. What is the tentative explanation of your research question? (Hypothesis)

3. In an investigation, there is only one variable to be changed.

Which variable will you change in this investigation? (Independent Variable)What is the tentative explanation of your research question? (Hypothesis)

3. In an investigation, there is only one variable to be changed.

Which variable will you change in this investigation? (Independent Variable)In an investigation, there is only one variable to be changed.

Which variable will you change in this investigation? (Independent Variable)Independent Variable)

4. All the other variables must be kept constant. What are a few important variables that will

affect the results greatly? (Controlled Variables)All the other variables must be kept constant. What are a few important variables that will

affect the results greatly? (Controlled Variables)(Controlled Variables)

5. What results will you measure? (Dependent Variable)Dependent Variable)

6. What are the materials and apparatus that you will need to carry out the investigation

(Materials and Apparatus)

7. What are the steps that you will take to carry out the investigation? (Procedure)

Step 1: ______________________________________________________________

Step 2: ______________________________________________________________

8. How are data collected? (Data collection)Procedure)

Step 1: ______________________________________________________________

Step 2: ______________________________________________________________

8. How are data collected? (Data collection)(Data collection)

9. How to show that the experimentation was carried out as reported? (Evidence)(Evidence)

Use of photograph, audio or video recording.

10. How to organize and present the data collected? (Results)(Results)

*The data can be presented in the form of tables and/or graphs.

11. What do the data mean? (Data Analysis)

12. What can you deduce from the discussion of your data analysis? (Conclusion)

Does it support your hypothesis? If not, what would you do?

13. How can you apply what you have learnt to everyday life? (Application)

14. What are the limitations of your experimentation? If you were to work on the same topic

again, would you conduct the experimentation differently? Why? (Limitation and further

improvement)

The Idea

The only problem with this idea is: it doesn't really fit into any of the Science categories. But I'm interested to find out the answer!

The situation: There was a recent newspaper article about a 3 year old Malaysian girl who died after her father had forgotten about her and left her sleeping in the car. The car was locked and windows were wound up. The car was parked under the blazing hot sun. By the time he remembered about her more than an hour later, the girl had already suffered serious heatstroke.

Quite a lot of people don't know that leaving somebody in the car with no ventilation or air-con can actually cause a person to die if it is hot enough outside. This is not the first time something like that has happened.
 (Actually, even with air-con on you can still die from carbon monoxide poisoning, but that's a different story)

Hence, I would like to find out: just how high can the temperature in the car get in comparison to outside temperature, and how long does it take to reach such a temperature? It must be in comparison to the outside temperature, because although Singapore's temperature is constant (equatorial region), there can still be slight fluctuation on different days.

Do different coloured cars affect the the time taken to reach this temperature? (e.g. darker coloured cars, orange etc.)

Do different location affect the time taken to reach this temperature? e.g. In a basement carpark, under a large tree, in an open area under hot sun.

Note: A person's internal body temperature reaches 40-44 degrees when he has heatstroke.

More Ideas

Rate of reaction of Vitamin C tablet - how fast will a Vitamin C tablet dissolve if placed in water of different temperatures?

Observation: When one fruit rots, the fruit in contact with it begins to rot too. Why? At what distance does this occur? Is it only when the fruit is touching the rotting part does it start to rot?

Experiments involving building simple rockets - putting Redoxon tablet in film canister, fill with water, turn upside down and let it shoot into the air

SIP Ideas

Ideas for SIP:

1. There is a myth that states that hot water will freeze faster than cold water, due to an effect called the Mpemba effect. One of the several possible explanations for this effect involves evaporation: if you start with extremely hot water, quite a lot of it will evaporate (and a smaller quantity of water will freeze faster than a larger quantity). And so, according to chemists, it is possible and not a myth.

2. Coca cola can remove gum from hair. The chemicals found in Coca-Cola will loosen the gum and make it looser and easier to pull out.

3. Some websites say that Coca-cola can remove rust because of the phosporic acid in the coke. However, others say that Coca-cola causes nails to rust as rust is caused by oxygen combining with the metal, in this case iron and steel. The acid in the coca-cola strip off contaminants and increase the speed at which this process takes place. Acid also has oxygen in it and when it meets up with various other items it makes more oxygen available for the process. Apparently, oil protects the nails by preventing oxygen from getting to the metal.

4. Do aerodynamic paper planes really travel faster than planes of other shape?

5. Which light source will cause dyes to fade the most? e.g. UV light, florescent light etc.