The short answer here is no. You do not need to rehydrate any of the yeasts we offer, and there will be virtually no negative affects on your final beer or cider product. 

That said, you can rehydrate your yeast if you choose.  To do this most effectively you will want to create a "starter."

  1. First, take about a cup of warm (95F-105F, 35C-40C), previously boiled water, and add it into a sanitized cup.  You may sanitize this cup with the boiling water having been cooled in the cup, or with a sanitizing agent.
  2. Next, Stir in the yeast you'd like to rehydrate. You should cover this mixture with a lid of some sort.
  3. You'll want to now add some food for the yeast by means of adding a form of sugar.  A teaspoon of malt extract or regular table sugar added to a small amount of boiling water will provide plenty of dissolved foods for your yeast. Only add this sugar solution to the yeast mixture once it has been cooled to the temperature of the yeast mixture.
  4. This will "proof" the yeast, and begin it's process of reproducing.  Make sure it's covered and in a warm area away from sunlight.
  5. Within 30 minutes to an hour, your yeast should be very active.  You'll know that it's active by the motion and sometimes foam being generated.  You're healthy yeast is ready to be pitched at this point.