µBrews Episode 8 - Performing Cell Counts with a Hemocytometer

Using an adequate pitch rates is critical to ensuring a healthy fermentation, while for some styles of beer, lower pitch rates are needed to ensure the yeast produce the desired flavour profile. Ensuring a correct pitch rate requires the ability to accurately determine the concentration of yeast in a yeast sample. This is done by counting yeast, using a specialized slide called a hemocytometer.
In this video I will explain what a hemocytometer is, how it works, demonstrate its correct usage, and walk you through how to calculate the concentration of yeast in a yeast pitch from hemocytometer counts. At the end of the video I will demonstrate how a hemocytometer can be combined with viability staining (trypan blue staining), thus allowing you to quickly and easily determine both the number of living yeast in your sample and your samples overall viability.
This is part of a video series on using microscopy in the home or craft brewery. A full list of published episodes can be found on my µBrews RUclips playlist, or on my blog at www.suigenerisbrewing.com/index.php/microbrews/
Outro music (in all its 8-bit glory): “New Hope” by Patrick de Arteaga: www.patrickdearteaga.com
NOTE: I mis-speak at 4:45, where I state the grid size in the inner region is 0.5 mm - its 0.05 mm