In the first two installments of “Clear Beer,” we examined various things you can add to your beer to enhance clarity and stability. From kettle finings such as Irish moss and its derivatives to cask finings such as isinglass and gelatin, there’s no shortage of substances you can use to clear up your beer. In this the final part of the series, we discuss a couple of additional ways to clarify your homebrew: cold crashing and fermentation enzymes.
Cold Crashing
Cold crashing is a low-budget yet effective way to achieve bright beer without any additives. The principle is simple: Just store your beer at a temperature near freezing for anywhere from one to eight weeks. Over that period of time, sediment will gradually precipitate out of suspension and fall to the bottom of the vessel. While the idea is easy, it might not be the ideal solution for all brewers for two big reasons.
- You need a refrigerator that’s big enough to hold a carboy or keg, and that has enough free space to accommodate it.
- It takes time. Some beers might clear up in a week; others may need a month or more.
Fermentation Enzymes
In Issue 6 (April-May 2015) of _Craft Beer & Brewing Magazine®, _we discussed how some professional brewers such as Stone have started relying on special fermentation enzymes to reduce gluten levels to near nil. The enzyme, available to homebrewers as White Labs WLN4000 Clarity Ferm, was first developed as a way to reduce chill haze. That it also reduces gluten is a happy side effect.
For the scientifically minded, here’s what the White Labs spec sheet has to say about Clarity-Ferm:
Chill haze in beer results from the precipitation of polyphenols and proteins during cold storage. The nature of this precipitation has been shown to be the result of hydrogen bonding between the polyphenols and the proline-rich fraction of particular polypeptides. This haze develops over time and, initially, is reversible (haze disappears when the temperature of the beer increases). As the hydrogen bonding becomes stronger, this chill haze can become permanent.
CLARITY-FERM will prevent the precipitation of polyphenols and proteins by hydrolyzing the sensitive (haze-active) polypeptides in the region where such hydrogen bonding occurs. The specificity of the enzyme ensures that no other beer parameters such as head retention or color are affected.
Got all that? Me neither. But you don’t have to know how it works to know how to use it. Just 10 milliliters (one vial) of Clarity-Ferm added to wort at the same time you pitch the yeast will break down the proteins that cause chill haze and leave you with crystal clear beer.
Keep in mind that Clarity-Ferm doesn’t do anything about suspended yeast. So if you’re working with a non-flocculent strain, you may still need to turn to cold crashing or a cask fining to get the bugs to drop.
I’ve found that a Whirlfloc tablet in the kettle gets me 90 percent of the way there on just about everything I brew. When I put a fresh keg in the kegerator, the next one in the queue goes into cold storage to carbonate. By the time it’s ready to go in, it has almost always dropped crystal clear.
In the end, clear beer is mostly about aesthetics, so you’ll have to decide how much effort you’re willing to expend for the sake of clarity.