Managing Beer Fermentation

    Published: 06-16-2009
    Views: 14,046
    Gary Glass from the American Homebrewers Association teaches you how to manage beer fermentation.

    Gary Glass: Hi! My name is Gary Glass. I am the director of the American Homebrewers Association. I am teaching you how to make beer at home. In this segment we'll cover managing fermentation.

    Now we've got our herbs in the fermentor. What I am going to need to do is take a reading of the temperature to make sure we're at the right temperature for adding our yeast. So I am going to sanitize some equipment. I am going to sanitize the thermometer and our hydrometer. And I am even going to sanitize the packaging for the yeast. You can't be too careful. So just getting a little sanitizer on the yeast packet itself will make sure that there is nothing on there that can get into the beer.

    We check our thermometer and this is a floating thermometer so I can just put it right into that bucket. Swirl it around a little bit. Make sure our temperature is evenly mixed in the fermentor. Give it a few seconds to get to temperature and it looks like we're right at about 73 degrees. You want to be between 75 and 65 degrees. So that's great, perfect temperature for this, we're ready to go. If for whatever reason, your temperature was off, you can put the lid back on, stick it in your sink with some cold water if you need to drop the temperature or some warm water if you need to raise the temperature. Just want to make sure you are in that temperature-range of 75-65 degrees, before you pitch your yeast. And pitching the yeast, that's the term for adding yeast to beer.

    Now take our hydrometer reading and what this is, it's a little floating device, it's calibrated and it's got markings on here to tell you the density of the beer. Stick this into the beer. Let it float and what you are going to read on there is the meniscus where it comes up to the edge of the hydrometer. And you're reading on the scale it has, it starts with 1.

    000. And for this beer we're expecting to get a gravity reading of 1.

    05. That's a pretty typical range for a beer that is about the gravity you'd have for a Pale Ale or in this case a Hefenweiser, produce a beer somewhere in the range of about 5% alcohol.

    And yeah, it looks like we're just about right at 1.

    049. Expecting to be somewhere in the range of 1.


    052. So right in the range where we want it to be. That's great! And now we want to add our yeast. So I take some scissors to cut and open it up, sanitize the scissors too for good measure. And like I said earlier, in the cleaning and sanitation segment, if we were using bleach, we'd have to make sure that everything was soaked for 15 minutes. We're using Star San so that only takes contact time of about 15 seconds.

    Cut this open and then we just pour it slowly in our fermentor. Okay. So we've pitched our yeast, we're ready to seal up the fermentor. I am just going to re-sanitize this fermentor lid as a precaution. Get that on and then we'll add our airlock. So as you can see, there is a little bit of sanitizer in the airlock. It'll probably take about 24 hours before you'll start seeing some activity but once the fermentation starts going, you'll see the carbon-dioxide bubbling through here. That'll get your fermentation going. You want to store this in a place where it's going to be between 75 and 65 degrees, that's your fermentation temperature for Ales. And you want to make sure it's in a fairly dark place, direct sunlight is not good for beer. It can cause off-flavors that actually smell like skunk. So light is bad for it, direct sunlight; incandescent light is fine. But sort of like our closet, it's a perfect place for your fermentation.

    Now, it's going to take about a week to a week and a half, maybe 2 weeks for the fermentation to complete, so just watch that airlock. You see when it stops bubbling, hasn't bubbled for a couple of days, you're probably done with the fermentation. And then you'll be ready to move on to the next step. So we've covered managing fermentation. Next up, we'll talk about getting ready to bottle.