By Chayma
The following article was written by Chayma, a Year 12 student who has chosen biotechnology as her field of study. This article is part of the work students do during the techclass in English on Monday afternoons.
1. What is the goal of the experiment?
The objective of counting yeast on a cell of Malassez (picture below) is to know how many yeasts there are.
2. The description of the experiment.
To tell the difference between the dead and the living yeasts, we use the “blue of Funk“ which is the name of the dye.
First, we need to colour yeasts which are in the beer thanks to the blue of Funk.
We can observe that the dead yeast become blue during the experiment; if they are not colored, it means that they are alive.
To allow the observation of yeasts through the microscope, we drop some yeasts on the cell of Malassez after their coloration.
3. The result of the experiment.
We can see the result of the experiment in the picture below: there are two dead yeasts in the middle because they are blue and the others are alive because they are not.
After counting the yeasts, we are able to calculate the concentration of living yeasts: in the beer, there are around 2,2*106 living yeasts per ml of beer.