Why do sliced apples turn brown?

In this experiment I am going to find out why and how long will it take for sliced apples to turn brown. Also, I will experiment which liquid ( vingar, salty water, olive oil ) will keep the sliced apples the freshest.
Sayeh Khorshid
Grade 5


I think that out of salty water, vinager, and oilve oil, salty water will keep the sliced piece of apple the freshest because based on my research vinegar and olive oil are made up of mostly acetic acid which will not help keep the apples fresh for longer in fact that could make the apples become brown faster. 


For this experiment I need to reserch why do apples turn brown. 


- How long does it take for apples to turn brown? 

- What makes apples turn brown?

- What liquds ( olive oil, vinegar, salty water)  help keep apples fresh for longer?


The first thing I will do is slice a apple into four pieces. On the first one I will pour salty water, on the next one I will pour olive oil, on the third one I will pour vinager, on the last one I will leave it how it is. After this  I will observe, take nots, and take pictures over the next 48 hours. During this time I will also be researching why do apples turn brown. At the end of the 3 days I will see:
- Which liqiud kept the apple the fresh for a longer amount of time?

- Why do apples turn brown?   


The first 24 hours salty water was doing the best. There was very little browning while vinegar was doing the worst. Vinegar was making the apple browner than the plain one. The plain one was pretty brown but not as brown as vinegar. The last one olive oil was very brown as well but still not as brown as vinegar. After 48 hours salty water was still fresh but was turning  brown. Olive oil was very brown while vinegar was still doing the worst. Vinegar was extremely brown. The plain one was pretty brown but not as brown as vinegar or olive oil



   liquids    After 24 hours          After 48 hours          Notes        
Olive oil Max oviase change Max oviase change Not as much as vinegar
Salty water No oviase change Min oviase change  
Plain min oviase change Max oviase change  
Vinegar Max oviase change Max oviase change  



In this experament I found out that out of salty water, olive oil, and vinegar salty water helped keep the sliced apple the fresh for a longer amount of time. During this time I also found out that the reason apples turn brown after you cut them is that when you cut an apple the  enzymes will react to the oxygen causing oxidation. The apple will produce melanin to protect the apple which makes the apple look brown.



If salty water works we can use it to aplay it to extend the apples life span. Lemon juice has already been tested on apples and works so if salty water works we will be able to save money and reduce required energy to compost the decayed apples.

Sources Of Error

Sources of Error:

- The amount of salt in the salty water

- The weather ( room temperature )

-  The type of vinegar


This was a self drivin project