Pilot Test

Instead of doing flowers, I will make the subject of my experiments vegetables instead. They are much more easily obtained and a variety of pigments can be found. I have pilot tested my experiment by immersing a lettuce leaf in vinegar for about 3 hours. The problem now is that the pigments from the lettuce leaf did not leach into the vinegar. This might be due to:

1.     Lettuce leaves do not have a lot of pigment.

2.     Vinegar is not strong enough to damage the cell membrane of the cells in the leaf to allow the pigment (chlorophyll) to leave the cells.

Due to the results of this mini experiment, I have decided to observe the changes in colour of the vegetable itself rather than the acid/alkaline, seeing as the pigments are not so easily leached from the vegetable. However, this means that my experiment is not quantifiable!

I will thus be testing the effect of pH value on pigments in vegetables. For anthocyanin, which is the red/blue/purple pigment, I will test on radish and purple cabbage. Then for carotene, which supplies the orange colour, I will use carrot. Lastly, green pepper and spinach to represent chlorophyll, the green pigment. 

I intend to recreate the pH range using vinegar and dissolved baking soda, by using different concentrations and also mixing them. The more diluted the vinegar and dissolved baking soda, the weaker they are as an acid and alkaline respectively.