Pitching Rate

The term pitch rate refers to the amount of yeast that is added to cooled wort. Pitch rate is generally referred to in cells per milliliter. Pitch rates make a dramatic difference in the final flavor and aroma profile of any beer. Ester production is directly related to yeast growth as are most other flavor and aroma compounds.

A low pitch rate can lead to:

• Excess levels of diacetyl
• Increase in higher/fusel alcohol formation
• Increase in ester formation
• Increase in volatile sulfur compounds
• High terminal gravities
• Stuck fermentations
• Increased risk of infection

High pitch rates can lead to:

• Very low ester production
• Very fast fermentations
• Thin or lacking body/mouthfeel
• Autolysis (Yeasty flavors due to lysing of cells)

External links

• Wyeast's page on pitch rates