As the concentration of cells increases, the turbidity of the culture increases.
A standard curve is produced by plotting the absorbance versus known cell concentrations (determined from a direct count using a haemocytometer)
- Concentrated yeast culture
- Turbidity meter
- Pasteur pipettes
Instructions – preparation of standard curve
Make serial dilutions of the yeast culture.
For each cell suspension obtained, measure the absorbance and calculate the cell concentration using a haemocytometer to directly count the cells. Where the cells are too numerous to count (TNTC), serially dilute the suspension till a countable number is achieved.