Filtering Homebrew – Pros and Cons

Should you filter your home brew? To filter, or not to filter? That is the question for many homebrewers who are just starting out. It’s inevitable that early on in the hobby, most home brewers will consider filtering their beer because they are a bit put off by cloudiness and the thick sediment they notice at the bottom of the bottle. But there are some things to keep in mind before you lay out the expense for filtering equipment and add another, possibly unnecessary, step into your homebrewing process.

Most commercial brewers filter their beers for a couple of reasons. The main reason is that they need to get the stuff to market, and can’t afford to have freshly brewed and bottled beer sitting around for months as it settles and ages. Also, the filtering process traps large protein molecules which can cause cloudiness upon chilling of homebrewed beer (you may have noticed this at some point). Filtering removes other particles too, creating a smoother tasting beer sooner, and reducing any natural haziness for a deeper, clearer appearance. However, filtering also removes yeast…

Consider these points.

  • Filtering works best under pressure so you’re better off having a kegging system to carbonate and pressurize the beer so you can force it through a filtering system prior to bottling or while transferring to a serving keg. You will no doubt run into a major delay and headache waiting for gravity to pull the beer through the filter system.
  • After much of the yeast is removed in the filtering process your beer will not fully carbonate in the bottle. A kegging system is required to carbonate your beer under pressure after filtering. So if you want to bottle your home brew you’ll still need to keg and force-carbonate it first, after filtering. This will require more equipment to control bottling the beer under pressure.
  • Secondary fermentation is highly recommended, and generally essential to producing a finished beer, whether you filter or not. Various processes occur during that aging stage that really contribute to a proper, finished flavor. Not to mention further settling which could eliminate the need for filtering anyway. Halting these processes by filtering will prevent your beer from reaching its full potential.

I am not some anti-filtering purist, but personally I’ve never had the need, or desire to incur the added expense, or process. My home brews are fermented in a primary for two weeks, then racked to a secondary glass carboy for another two weeks at least. I’ve allowed some of my brews to settle in the secondary for up to three weeks before bottling. After bottling it’s another two weeks to settle and condition, and to this day I have not had a cloudy beer, unless it’s a wheat. My final sediment is super thin too, I’ve actually had my home brews right out of the bottle!

Ultimately, if you’re brewing equipment and bottles are clean and sanitary, and you allow sufficient time for settling in a secondary fermenter before bottling, and you allow sufficient time for the beer to settle and mature in the bottle, you will end up with a great tasting beer. Filtering will speed up the process, but is the expense, extra time, and inevitable hassle for the newbie really worth it? That’s a personal choice.

Obviously you can take your hobby as far as you want to go, and it wouldn’t be an adventure if you didn’t try new things. But consider all the pros and cons before stepping in to the world of beer filtering. I recommend these other sources for more specific information on the subject:

BeerSmith: Filtering Home Brewed Beer

Filtering thread on Homebrew Talk

Beer glass image courtesy: Idea go /