How to rehydrate dried yeast properly
Yeast rehydration is the process whereby dry yeast is rehydrated and “brought to life” from its dormant passive state.
The “standard” method of rehydration is as follows:
Image from Lallemand
Don't wait longer than the 16-20 minutes before pitching the yeast as the yeast will slowly start dying off as it wants to start feeding but there are no nutrients to feed on.
Also, don't add any nutrients or other additives (like di-ammonium phosphate - DAP) to the rehydration water as it is toxic in high quantitiies to the yeast. The yeast requires only clean water to rehydrate (or actvator when doing strong sugar washes).
When making a yeast starter do not allow the Brixx value to be higher than 26 (when NOT using yeast activator) or higher than 34 (when using yeast activator)