[an error occurred while processing this directive]
Chapter 9 - Fermenting Your First Beer
9.3 Conducting the Fermentation
Pitching the Yeast
If your rehydrated and proofed dry yeast is not showing signs of life (churning, foaming) after a half hour, discard it and use the backup yeast, repeating the re-hydration procedure.
1. Pitch (pour) the yeast into the fermenter, making sure to add it all. It is best for the yeast if they are the same temperature as the wort you will pitch them to, and it is best for the beer if wort temperature is the same as the fermentation temperature. For Ale yeasts, the fermentation temperature range is 65-75°F.
2. Put the fermenter lid in place and seal it. But don't put the airlock in quite yet; we want to shake this up. Place a piece of clean plastic wrap over the hole in the lid and insert the stopper.
3. With the fermenter tightly sealed, place it on the floor and rock it back and forth for several minutes to churn it up. This mixes the yeast into the wort and provides more dissolved oxygen that the yeast need to grow. If any wort leaks out, wipe it off with a paper towel that is wet with your sanitizer solution. Place the sanitized airlock and rubber stopper in the lid. The airlock should be filled to the line with sanitizer solution. Many people use vodka or plain boiled water as alternatives. You want something that will not grow mold or contaminate the batch in case it inadvertently gets sucked inside the fermenter.
Active fermentation should start within 12 hours. It may be longer for liquid yeasts because of lower cell counts, about 24 hours. (Although if you made an adequate starter, it should start every bit as fast as dry.) The airlock will bubble regularly. The fermentation activity can be vigorous or slow; either is fine. The three important factors for a successful fermentation are pitching enough yeast, good wort nutrients, and maintaining a consistent temperature in the correct range. If you do these right, it is common for an ale's primary fermentation to be done in 48 hours. Three days at 65-70¡F for primary fermentation is typical for the simple pale ale being described here. Once the bubbling slows down however, do not open the lid to peek. The beer is still susceptible to bacterial infections, particularly anaerobic ones like pediococcus, and lactobacillus, which is found in your mouth. If you really want to look, peek in through the airlock hole, but keep the lid on.
Here is where you will need to make a decision. Are you going to use single stage or two stage fermentation for your beer? If you are going to use single stage, i.e. just this one fermenter, then you have nothing further to do but to leave the beer where it is for a total of 2-3 weeks. The conditioning processes will proceed and the beer will clear.
Racking is the term for the process of transferring the beer without disturbing the sediments or exposing it to air. Usually this is done by siphoning. If you have a bucket fermentor with a spigot, then transfer becomes simple. It is imperative to not aerate the wort during transfer after primary fermentation. Any oxygen in the beer at this time will cause staling reactions that will become evident in the flavor of the beer within a couple weeks. Always transfer the beer slowly and keep the outlet tube beneath the surface of the beer as you fill the secondary. Don't let the stream guzzle or spray as you fill. The only way to combat aeration damage is to introduce young beer to the fermenter at bottling time. This process is called "krausening", and is a time-honored method of carbonating beer, but it is an advanced technique that I do not cover. See Siphoning Tips in Chapter 1 - Crash Course for more info on good siphoning procedures.