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The yeast starter tool lets you determine the size of yeast starter to use for a batch of beer. Pitching the correct number of cells in a batch of yeast is important as it optimizes fermentation and reduces the chance of off-flavors or incomplete fermentation. Yeast starters are typically made from liquid yeast packages to increase the number of viable cells before pitching your yeast into the wort at the start of fermentation.

Yeast starters are rarely required when using dry yeast or slurry. Dry yeast is simply hydrated using a small amount of warm water about 30 minutes before pitching. Slurry is typically harvested in sufficient quantity for reuse.

Note that the pitching rates and internal values used by this calculator can be adjusted in the Options Dialog Yeast Tab. Also, you can perform starter calculations within a recipe using the Yeast Starter Tab within a recipe.

New Feature: The yeast starter is entirely new in BeerSmith 2.0

Online Articles: Yeast Starters Part 1, Yeast Starters Part 2, Making a Yeast Starter, Beer Yeast and Fermentation, Chris White Podcast, Chris White Interview

Using the Yeast Starter Tool

o	Select the Yeast Starter Tool from the Tools menu or ribbon.

o	Enter the properties of your target batch of beer including the type, volume (into the fermenter) and original gravity. This will determine the number of yeast cells needed for this batch of beer. Note you can adjust the pitch rates for different types of beer in the Options Dialog Yeast Tab.

o	Since yeast cells do die off (lose viability) with age, you can include the age of your yeast in the calculation. Check the "Estimate viability from age" to determine the percent of viable cells and include it in the calculation.

o	For viability, enter the yeast form and its production date (or harvest date if using slurry). This will determine the remaining viability of the yeast pack as of today's date. The viability rates can also be adjusted from the Options Dialog Yeast Tab.

For a Liquid Yeast Starter

o	If using liquid yeast, enter the starter pack cell count. The large Wyeast and White labs vials/smack packs have about 100 billion viable cells each, while the small Wyeast packs have only about 20 billion cells each.

o	Using a stir plate when growing your starter can significantly reduce the size needed. Check this box if using a stir plate

o	The tool will display the number of yeast packs needed and also the starter size needed. It will also show the number of packs that would be needed if you don't use a starter at all.

For Dry Yeast

o	Dry yeast does not generally require a starter - instead the appropriate number of dry yeast packs are hydrated about 30 minutes before use

o	The tool will display the number of packs needed (most homebrew yeast packs are 11 to 11.5 grams each).

o	It will also show you the volume of warm water needed to hydrate your yeast.

For Yeast Slurry

o	Yeast slurry is typically collected from an already fermented batch of beer and used within a few days for a follow-on batch. It is not used with a starter.

o	The tool will show the volume of thick yeast slurry needed for the target batch.

o	Note that yeast slurry loses its viability rapidly - and must generally be used within a few days of collection