OnTap Magazine

In my work I’m often privileged to teach absolute beginners how to brew beer at home. Over the years, homebrewers who are new to the hobby have come to me with a host of misconceptions and brewing myths in need of careful examination. And while I have fielded countless questions, there’s no doubting that a few usual suspects rear their heads again and again. I whittled those oft-posed queries down to the three most common misunderstandings, myths and questions that I’ve encountered in my life as a homebrew instructor. C O M M O N M Y T H 01 C O M M O N M Y T H 02 WHEN THE BUBBLES STOP, FERMENTATION IS DONE YOU CAN’T MAKE GOOD BEER WITH EXTRACTS If there is an overarching myth that novice (and some not-so-novice) homebrewers believe, it’s that the bubbler or airlock is an accurate indication of fermentation. It is not. But I understand why it’s an easy one to believe. After all, other than opening up your fermenter, how do you know that fermentation is actually happening? So, those comforting bubbles ploop- plooping their way out of the airlock become the proxy for fermentation. The trouble starts when the bubbling stops. This usually creates a fair amount of anxiety for beginner homebrewers because if bubbles equal fermentation, then no bubbles must mean no fermentation. Right? Wrong. To understand why a cessation of bubbling does not mean that fermentation has ended, you need to understand two things: 1 Your airlock and fermenter system is not hermetically sealed. There are plenty of microscopic gaps between the gasket, airlock, and fermentation lid to allow the escape of fermentation gases (mostly CO2). Thus, there will be a gradual drop in pressure as more of these gaps are exploited by gases trying to get out. In part, this is a good thing. Why? Because if your fermenter was completely sealed and gases were also expanding inside it, you would have what experts like to refer to as a bloody dangerous situation. Yes, you would have created a beer bomb. 2 Primary fermentation is fast. Homebrewers often don’t appreciate just how rapidly primary fermentation takes place. In general, and if you hydrated your yeast or are using liquid yeast, it takes about three days for primary fermentation to do its thing. Now, that kind of fermentation is a violent process. It will almost certainly create some kind of activity in your airlock. In that sense, the only thing a bubbling airlock is good for is to tell you that fermentation has started. However, if you’re using a large fermenter with loads of headspace, there won’t be enough pressure to create bubbles. At most, you may notice that the sterile liquid you’ve filled the airlock with has risen slightly. If the first few days of fermentation are the thrash metal of brewing, then the next stage is more like a slow, syrupy number by Mr Barry White. It’s a gentle and subtle process that helps to finish the beer, integrate flavours and get rid of various undesirable compounds that are normal by-products of fermenting wort. And while it is an essential process, this second stage of fermentation will not necessarily create bubbles in the airlock. Once you understand these two principles, you should start worrying less about a lack of bubbles. Ultimately, the only sure-fire way to know anything about the progression of your fermenting beer is to use scientific measurement. Here’s how: Take a sample (carefully and with sterilised equipment) and use a hydrometer or refractometer. Both of these instruments will tell you the gravity of your beer. Your recipe will tell you the expected final gravity, and that way, you The trouble starts when the bubbling stops can tell if your beer is ready to be bottled or kegged. A note of caution: Try to control your anxiety and only take your first measurement after one week of fermentation. The more you open your beer to the outside world, the more you risk creating problems for your beer (either due to contamination or oxygenation). Many homebrewers new to the hobby are surprised when I begin my brewing lessons with recipes using malt extract (usually dried malt extract) along with some speciality grains, such as crystal malts. This might be because they’ve been exposed to the second myth I’ve encountered a lot: that you can only make good beer using full-grain (AKA all- grain) brewing methods. While full-grain brewing is certainly loads of fun and allows you full access to all styles of beer to be found in the BJCP guidelines, extract brewing has a lot going for it as well: • It requires minimal equipment. Usually, once you have a big pot, a gas burner and your fermenter, you’re good to go. • It teaches the basics of good brewing. A lot of bad beer is made when brewers don’t understand the basics, things like how to handle hops and yeast, how to keep things clean, and how to bottle or keg your beer properly. All of these vital elements of successful brewing can be learnt through extract brewing. ontapmag.co.za | Winter 2020 | 53