Hop Dad

Getting Started, Part 4 – Fermentation

September 9, 2011 at 4:00 pm Leave a comment

Now that your beer is brewed and resting comfortably, fermentation can begin.

Bubbles, Bubbles, Bubbles!

The obvious sign of active fermentation is bubbles in the airlock. Some yeast strains are slower to start than others but all should show signs of fermentation within 24 hours of pitching. During the next few days primary fermentation will occur at a rapid pace. Check on the fermenter a couple of times a day during this phase because…

BOOM!

Sometimes the airlock pops off the fermenter. This happens if fermentation is so active the airlock can’t keep up, the airlock gets plugged with foam (krausen), or the airlock is improperly positioned in its rubber plug. If this happens, just clean out the airlock, sanitize it and put it back in place.

Other clean up may be necessary if foam and fluid has sprayed about. Make sure you get that airlock cleaned and replaced first, though. Then go about cleaning the rest of the mess.

You might consider using a blow-off tube and bucket instead of an airlock. This set up is a simple plastic hose where one end fits snugly into the hole in the fermenter lid or carboy and the other end goes into a bucket of sanitized fluid. Then as fermentation occurs the CO2 goes out the tube and in to the bucket of fluid. You may decide to use a blow-off tube during the primary fermentation phase of all of your brews, particularly if you use very active yeast strains and create high gravity beers.

No peeky!

Primary fermentation takes about 1-3 days but it takes a little longer for the yeast to do all of their work. The best guideline is to let the beer sit for a week (that also lines up nicely with Hop Dads’ schedules). Do not be tempted to peek in the fermenter during this time because you don’t want to run the risk of contaminating the beer. Just let it do its thing.

Racking and Secondary Fermentation

When primary fermentation has subsided and the beer has sat for a few days you need to take a sample and check the specific gravity. We need to know if the yeast has done its job and reached our target gravity. If it has, then you will want to transfer the beer to another container where the yeast can clean up after itself.

Racking your beer to a secondary container has two immediate benefits: it helps to clarify your beer, and removes residual materials that could cause problems for the remaining active yeast cells. During primary fermentation most of the yeast has eaten up as much sugar as it cares to and has begun to clump together. Those clumps then fall to the bottom of the container where it will join other materials such as hop sludge from pellet hops, and dead yeast cells. When you transfer your beer to the secondary fermentation container you will want to leave these bits behind.

Once the beer has been moved to the secondary container the remaining active yeast cells can finish consuming any other available sugars left in the wort.

Moving to a New Home

Racking your beer to secondary is a pretty easy process depending on what container you have for primary fermentation. I use a bottling bucket with a spigot for primary fermentation. All I need to do is set the bucket on the kitchen counter, attach a sanitized hose to the spigot, put the other end into a sanitized carboy on the floor, and open the spigot. When the beer is transferred I put a sanitized airlock on the carboy and tuck it back in its dark, comfy fermentation spot.

If you are transferring your beer from one carboy to another you’ll need to use a syphon, or racking tube.

Here are some tips:

• Make sure everything that touches your beer has been properly sanitized.
• Putting the primary fermenter in place for the transfer will rouse some of the materials at the bottom. Once I have the container on the kitchen counter I usually wait about 20-30 minutes for the beer to settle down before I rack it.
• Do your best to prevent the beer from splashing, foaming, or otherwise swirling about as it transfers to the secondary container. We want to limit exposure of the beer to oxygen. The best technique I’ve found is to let the tip of the transfer hose sit just under the surface of the beer.
• If you have an extra airlock, sanitize and use that airlock on the secondary. Since primary fermentation can be so active that it sends materials into an airlock, starting with a clean, sanitized airlock is just a good idea.

Caveat Cervesarii

Racking your beer to a secondary container involves risks that some home brewers just aren’t willing to take. By exposing your beer to air you run the risk of oxygenation, which can create off flavors. Also, there is the risk of exposure to bacteria from improperly sanitized equipment. I haven’t had any problems racking my beers to a secondary so I will continue to do it. Like most elements of brewing, you will develop your own preferences as you gain more experience.

Entry filed under: Brewing. Tags: Brewing.