Primary fermentation is dependent on several environmental variables, but generally begins within 24-48 hours after the yeast is pitched, and lasts about 3-5 days. I gave mine a week to be sure it was complete before transferring it to a new vessel. Secondary fermentation is an optional step, but is recommended for promoting desirable flavor and clarity in the beer.
I began the process by cleaning and sanitizing all of my equipment, including a five-gallon carboy with a stopper and a new airlock, an auto siphon, and a length of food-grade tubing. I also boiled some water for the new airlock and set it aside to cool.
I hefted the fermentation bucket onto the counter and placed the empty carboy just below it on the floor. With sanitized hands, I removed the lid from the bucket and set it aside. Since primary fermentation had completed, this was the appropriate time to take a final gravity reading, and I did so, repeating the process I used to measure the original gravity. I recorded the number to perform my ABV (alcohol by volume) calculations later.
I resanitized my hands and grabbed the auto siphon. I plunged one end of it into the beer, carefully holding it a few inches above the bottom, and extended the tubing into the mouth of the carboy with my other hand. With everything in place, a couple of solid pumps sent the siphon into action, effortlessly moving beer from the fermenting bucket through the hose and into the secondary carboy.
After that, all I needed to do was keep the end of the auto siphon out of the sludge at the bottom of the bucket and wait patiently for the beer to transfer into the carboy.
Nearing the end, it became necessary to tilt the bucket to get as much beer out of it as possible. Even then, some beer was left behind in the interest of picking up as little sludge as possible. This sediment is made up mostly of flocculated yeast cells. Flocculation occurs as fermentation slows and yeast cells that are suspended in the beer begin to clump together en masse and settle to the bottom of the fermentor to join any leftover hop material and loose grain particles that have settled out during primary fermentation. Together, they form a slimy beige sludge known as “trub.” It's not harmful to the beer, but it's best for the clarity of the beer to leave as much sediment behind as possible.
When I was finished with the transfer, I removed the auto siphon and plugged the mouth of the carboy with the sanitized stopper (also known as a "bung").
I pressed the new airlock into the stopper, and filled it with the sanitized water. Then back into a cool, dark place it went for a week of secondary fermentation.
Magical darkness once again. Check back on DIY next Wednesday for Judy’s post on proper bottling… and subsequent drinking.