Our class is doing a practical SAC using beetroot to explore our understanding of membranes. The main thing that we need to understand is why the solution (that the beetroot was placed in) changed colour.
So here are the different solutions: distilled water, pH 4, pH 7, pH 9.2, alcohol 1%, alcohol 25%, alcohol 50%, detergent 1%, detergent 5%.
Separate to this the beetroot was placed in temperatures of 0,10,25,40,50,60,70 degrees.
The results indicated that alcohol and detergent cause most pigment leakage (about 3-4/5 on a scale). Varying pH had a small effect, as did distilled water (about 2-3/5).
One interesting result was that pH 9.2 resulted in a colour leakage rating of 1 after 30 mins then change to 0 after 24 hours. What is an explanation for this?
For temperature, the colder, the more leakage and the warmer, also the more leakage. Temperatures 25 and 40 both showed little to no colour loss.
How do you explain these results?