There are two types of yeast that home brewers use when fermenting their beer. You have dry and liquid yeast available. We’ll cover both types, the pluses and minuses of each, and how to prepare them for use. Let’s start with dry yeast.
Dry yeast can be sprinkled right into the cooled wort if you want. You do not need to rehydrate, but some people still like to get the yeast going before they pitch it. This is what you need to do if you plan on rehydrating it:
- Add 1 cup of 80° F water to sanitized container.
- Add 1 package of dry yeast to the water.
- Stir the water and yeast mixture for 30 seconds. Do not stir vigorously.
- Let the yeast sit for 15 – 30 minutes until you notice a light foam forming on top of the liquid.
- Pitch (add) the yeast to your fermenter.
Liquid yeast is available from two main manufacturers, Wyeast and White Labs. Liquid yeast should be stored in the refrigerator until use. We will talk about each one individually because how you prepare them for use will differ.
Wyeast comes in activator packs.
The Wyeast Activator packages include a sterile liquid nutrient pouch that, when “smacked”, releases its contents into the yeast slurry and “activates” the package. The available nutrients initiate the culture’s metabolism which in turn generates CO2 and causes swelling of the package. This process will reduce lag times by preparing the yeast for a healthy fermentation prior to inoculation. Activation also serves as a viability test of the culture. Expansion of the package is an indicator of healthy (viable and vital) yeast. Although beneficial, cultures do not need to be activated prior to inoculation.
We’ve found that you can pitch an Activator pack directly into a 5 gallon batch with good results. It may take a bit longer for the fermentation to begin, but this will work just fine. However, if you are brewing a higher gravity beere, like an Imperial Stout or Bigfoot’s Barleywine, then you should make a yeast starter. For more information, see our PDF titled “How do I make a yeast starter?” Here is how you prep an Activator pack:
White labs come in what looks like a test tube or in their PurePitch packaging . You can either pitch the yeast right into your wort, or make a yeast starter if you choose. For more information, see our PDF titled “How do I make a yeast starter?” Most brewers will pitch the yeast right into the wort. Here is how to prep for using White Labs yeast:
That’s all you need to do with White Labs!
Note: Yeast can take 24 – 72 hours to show signs of fermentation. Give the yeast time to work before you start becoming concerned. If after 72 hours and no signs of fermentation, add dry yeast. If you are not sure if the yeast has worked or not; take a hydrometer reading, or taste the beer. If it is very sweet, the yeast has not worked. Dry yeast may start in a couple hours, but it can ferment a beer in less than 12 hours.
If you are not sure about the viability of your yeast then make a starter first. This will give you the opportunity to ensure that the yeast is working before you pitch it into your wort. Even if there are only two yeast cells left, that is all you need to ferment a beer.