Secondary Fermentation: A Homebrewer’s Guide

If you are new to brewing your own beer, it is important that you learn how the process of fermentation works and the steps you should take to make the perfect homebrew. For some beers, you may want to follow a secondary fermentation process. This conditioning process is a little more complicated, but if you understand the phases, you will be a pro-brewer in no time.

Here’s our tips for understanding the process of secondary fermentation, how it works and when you should do it.

Understanding the Phases of Fermentation

In order to make beer, you must allow it to ferment for a short period of time. The first few phases of fermentation occur fairly quickly. In the aerobic phases, or first phase, the yeast cells become accustomed to their environment and begin to multiply. This multiplication happens very quickly, but not a lot of alcohol is produced.

Oxygen is needed during this phase by the yeast for it to work. The first phase lasts a few hours and you will not be able to see what is going on unless you have a microscope. Once this process is complete, it moves into the anaerobic phase, where the yeast will metabolize the sugars into Ethanol and CO2.

This reaction causes there to be foam, or krausen, at the top of the beer that is fermenting. This active phase of fermentation will usually last anywhere from a few days to a whole week.

Towards the end of this phase, the foam will subside and the yeast cells will die or go dormant, falling to the bottom of the container. However, not all of the cells will do this. A few of them will ferment slowly for several more weeks in the conditioning phase.

When Should You Use a Secondary Fermentation?

When it comes to brewing beer at home, there are some cases where you should definitely think about using a secondary fermentation. If you are making Lager or a high-gravity beer such as Barley Wine, it makes sense to go ahead with the secondary. You can also use this fermentation if you are really picky about your beer.

The fermentation process takes a long time with both Lager and Barley Wine, so you don’t want it to sit in the first container with the bitter beer yeast at the bottom for very long. Many homebrewers like to get the beer out of the first container as soon as the active yeast is done with its cycle, whether they are using a secondary fermentation or not.

5 Tips & Tricks for Secondary Fermentation

Consider these tips and tricks if you decide to follow a secondary fermentation process when making your beer.

  1. Sanitize
    Make sure all of the equipment you use to make your beer has been thoroughly washed and sanitized. Honestly, this cannot be stressed enough. You do not want any unwanted germs, leftover residue or other substance to contaminate the beer you’re working so hard to make. And this is precisely what will happen if you don’t properly sanitize your equipment.
  2. Don’t pour, siphon
    When it comes time to move your fermented beer from the first container into the second, it would be wise to slowly siphon the beer instead of pouring it. If you pour the beer, oxygen will get mixed into it and start your yeast into the first phase again. You want to keep the yeast in the anaerobic phase.
  3. Take care when Lagering
    If you are making Lager, you will need to lower the beer temperature. To avoid water being sucked from your airlock back when the beer contracts, you can place an air filter in the place where the airlock normally is so that the beer can cool.
  4. Be smart when using a Carboy
    If your secondary container is a Glass Carboy, keep it in a dark area or cover it with a blanket. The sunlight can ruin the beer and make it taste/smell slightly skunky.
  5. Don’t forget about the beer
    During the secondary fermentation process, it is easy to forget about the beer. Keep an eye on what the beer is doing and how bubbly it is. If you wait too long to bottle the beer, then you may ruin it. Alternatively, if you bottle it too early, you could also ruin it. The length of time your beer needs to condition all depends on what style you are brewing. Do your research, take plenty of notes, and you will be fine.

Brewing your own beer can be a tricky business. There is a lot of information for you to know and understand about the fermentation process.

If you decide to follow a secondary fermentation process, do not get frustrated if it does not work out for you the first time. It will probably take a little bit of practice to get the job done correctly.

Just remember, practice makes perfect. Once you figure it out, you will have great some very tasty homebrew to enjoy with your friends and family.

Related Homebrew Articles:

Jeff Flowers

About Author

Jeff Flowers has been a self-described beer geek for over a decade now. When he's not chasing his daughter around, you can usually find him drinking a fresh brew and wasting too much of his time on both Google+ & Twitter.


    • David Hess says

      Impressive! Have the all turned out well or did you have to toss a few? I still consider myself a novice though I have brewed roughly 15 batches (tossed a couple). Secondary fermentation intrigues me. I have heard the process will improve clarity and make the bear less bitter. I am considering this for an IPA that I have planned. Further research is needed….

  1. Bob Bockmann says

    I have had a few higher gravity (1.080+) beers finish in primary within about 2-weeks when I transferred them to a secondary (glass carboy). Some show signs of weak activity, while others show no activity at all. If there is no activity, am I better off bottling right away, or continue to let them hold for a full 3-6 weeks?

    • Dan says

      You really don’t see much activity in the secondary phase of fermentation. This phase is a slow not very active phase in which the remaining yeast making the beer better (simple terms). If you want to really know whats going on during secondary grab a brew book they are full of awesome information and break down what is going on during this phase.

  2. kyle says

    I use a secondary everytime sometimes there is activity sometimes it does not appear to have activity. I prefer to get it off the trub as soon as the foam has reduced. Lots of dead cells down there that i dont want the flavor of in my beer.

  3. Ed Staib says

    I’m on my second brew. The first brew had some activity on the first couple of days in the airlock but it turned out fine. This second brew an oatmeal stout and the second day after brew day it bubbled a little but that was it. I was advised to give it a total of seven days then switch to the secondary-which is what I have done. Hopefully this will turn out well. I wonder if it’s because it’s a 1 gallon batch? Anyone have any ideas?

  4. marco says

    I have been brewing for about a year and half now and have always been told to only use secondary when adding other ingredients to the beer. If brewing a big beer such as a barleywine would it be a good idea to pitch more yeast? I have been reading about top cropping and wonder if pitching this yeast in the secondary would be beneficial.

  5. Zac says

    It is important to note that secondary fermentation is not entirely necessary. With today’s yeast and a healthy fermentation you often accomplish everything you need to in primary. I would only recommend secondary fermentation for beers that you plan on aging extensively before bottling OR if your primary fermentor is a plastic bucket. Plastic fermentors have the added risk of oxidation over an extended period of time, as the plastic will slowly allow oxygen to permeate into your beer and create a stale flavor. Should your primary fermentor be glass, you have no worries provided your yeast is healthy to begin with and sanitation measures were taken accordingly.

Leave a Reply

Your email address will not be published. Required fields are marked *