In beer brewing, what is the primary goal when preparing a yeast starter culture before pitching?

Answer

Multiplying the desired *Saccharomyces* strain

A brewing yeast starter is intentionally built up to increase the population of the specific desired yeast strain, although unlike sourdough, the goal in brewing is usually to exclude unwanted bacteria.

In beer brewing, what is the primary goal when preparing a yeast starter culture before pitching?
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