Homebrew Clarity

Most homebrewers don’t worry too much about the clarity of their brew as long as it tastes good and smells good.  We don’t have all the fancy filters that the big boys use, and most of the time the beer is “clear enough” for our standards without a lot of extra work.  However, if you plan to put your beer in a contest and it happens to be a Kolsh, Pilsner, or IPA instead of a porter, stout, or wheat beer then the appearance could be a deciding factor between your beer and another one that is equal in flavor and aroma.  Since several of us are probably interested in entering our beer into this year’s festival contest, I did a little research and found some good tips on how to get the best clarity from your homebrew.  I found numerous sites with tips, but this one seemed to summarize what all of them said in one post.

The number one cause of haze in homebrew is called chill haze. Where does this haze come from? It comes primarily from the malt you use. The malt is full of proteins and its husks are full of tannins (polyphenols). These proteins and tannins (along with other polyphenols) cross-link to form small complex chains which are too small to settle out. These protein-polyphenol complexes are soluble at warmer temperatures but will become insoluble at colder temperatures, and form the haze you see in your homebrewed beer. These small protein-polyphenol chains can combine with oxygen to form larger chains which can settle out, reducing chill haze. But the clear beer comes at a price, oxidation and staling. There are some things the homebrewer can do to reduce chill haze. To reduce chill haze caused by protein-polyphenol linking is a matter of reducing the proteins or the polyphenols (aka Tannins) or both.

The three main culprits that cause cloudiness in beer are proteins, yeast, and tannins. Here are some thing you can try:

  1. Reduce malts in recipe, minimize adjuncts
  2. Add specific adjuncts like corn or refined sugar
  3. Use high alpha hops for bittering
  4. Good hot break and quick cool down
  5. Fining agents such as Irish moss
  6. Batch sparge
  7. Filter
  8. Cold crash, secondary, and cold storage
  9. Skim and whirlpool before fermentation

Those are the nine most useful tips summarized.  Here is a total of 13 tips broken down with more explanation….

1.To reduce the protein and/or polyphenol levels in your beer, you can reduce some of the malt used in the recipe.
2. Try adding some adjucnts like corn, rice, or refined sugar such as the American lagers, Belgian-style tripels or strong ales have.

Several articles I read mention that a lot of cloudiness comes from adjunct grains. Keep the grain bill simple on these styles. Stick with your base malt and less than 10 percent crystal malt for an IPA. While tip number two mentions adding adjuncts the examples are specific. I did notice refined sugar in several IPA recipes. It is there to help dry the beer out, so use sparingly according to how dry you want the final product.

3. Hops also produce polyphenols in your beer. Using lower alpha acid hops as your bittering hops will incorporates much more hop cone material into your wort and thus more polyphenols are extracted. Using high alpha acid hops for bittering will reduce the hop-derived haze in your beer.
4. Try adding a protein rest which will reduce the large proteins into small and medium sized ones.

Tip number three is a common one I found in my searches, but if you are using well modified malts (You probably are) then ignore tip number four. Using a protein rest is unnecessary when using well modified malts, which most homebrew malts on the market are. As a matter of fact I read a few articles that mentioned the possibility of this stripping too many proteins away in well modified malt and making the brew suffer on mouthfeel and body.

5. Achieve a good hot break by boiling the wort vigorously and then get a good cold break by using a wort chiller (possibly even a pre-chiller). Switching to a more efficient chiller such as a The Therminator will get your beer chilled more quickly. A large percentage of malt polyphenols survive the boil and chill, whereas a relatively small percentage of hop-derived polyphenols will.

6. Use a fining agent in your boil, such as Whirlfloc or Irish moss, to reduce the large proteins. Adding bentonite to the boil in the last 15 minutes will reduce the protein and polyphenol levels significantly. Try adding 10-40 grams per 5 gallon batch, but remember that bentonite absorbs a lot of water too, so you may want to go with the lower end of the recommendation.

Tip number five is one that Dee and Derrell have advised to me in the past. Getting a good hot break with a vigorous boil is important. After the hot break is over, you can turn things down to save on propane to a level that will retain a gentle to medium boil. A good hot break helps break up also helps break down proteins you can leave behind later. The same goes for the quick cool down. Using a fining agent is good practice too. There are a lot of them on the market, but from reading reviews the Irish moss and Whirlfloc seem to have the best results.

7. Adding fining agents after the boil to reduce protein levels is a common practice commercially. Try Isinglass-a protein collagen from the swim bladders of the sturgeon and other fishes, gelatin-a byproduct of collagen production from animal hooves and pigskins, polyclar/pvpp-an insoluble white plastic powder which electrostatically attracts polyphenols, including tannins, as it quickly sinks to the bottom, silica gel-a polymeric hydrogel (or xerogel) made from sodium silicate which will preferentially absorb proteins (note: silica gel must be allowed to settle and be racked off prior to consumption, it is not approved by the FDA for ingestion), Polyclar Plus-a combination of silica gel and polyclar, and sparkalloid-a polysaccharide in a diatomaceous earth (DE) carrier which removes yeast cells and polyphenols as it sinks to the bottom (in fact you may need to add more yeast if bottle conditioning).

8.Try using a batch sparge, which is known to reduce the amount of tannins extracted from the husks.

Most of the time, fining agents after the boil are not necessary, but it is good to know the products. If you do every other tip and still end up with a cloudy beer, most of these fining agents can still be used in the keg. A common one used in the keg is unflavored gelatin. With tip number eight, this is the method I use all the time, but just because it is easier and requires less equipment. However, other homebrewers will argue that continuous sparging is better. I leave this tip up to you.

9. Filter your beer. Use a larger filter first, then switch to a small filter for polishing.

10. Make sure you lager at near freezing temperatures (32°F or 0°C).

11. Minimize aeration during bottling and kegging. Increased dissolved oxygen in your bottle can promote permanent chill haze.

You can spend money if you feel like it on fancy filters which can be used after the beer is finished, but I wouldn’t. One thing I did spend some small cash on was some micron bucket filters called EZ filters that you go through from the kettle to the fermentation bucket. These fit perfectly in a six gallon fermentation bucket, but wouldn’t work if you use carboys. If you are interested you can get some at this link. I use the 200 micron ones and it gets rid of a lot of trub and proteins.

Storing the beer at near freezing temperatures is good practice even for ales. As a matter of fact, one the best ways to ensure a clear beer is to cold crash it and secondary it. Here is the low down on this:

Storing beer under refrigeration, called laagering, helps to clear beer rapidly. At lower temperatures it is more difficult for the yeast, tannins and proteins to remain suspended. Cold stored beer will clear much more rapidly than beer stored at room temperature. Note that if you are bottling or naturally carbonating a keg, you need to wait for the beer to become fully carbonated before laagering. Otherwise laagering may slow or kill the yeast resulting in a poorly carbonated beer.

So, after fermentation is complete at regular ale temperatures the beer should not immediately go to the keg. Mr. Wizard advises:

One of the best ways for homebrewers to clarify beer is to simply move the carboy to a refrigerator and hold it cold (38° F is ideal)for at least a week. Chilling accomplishes several important things. The most obvious effect of chilling is that a big portion of the total yeast in suspension will “flocculate” or drop to the bottom of the fermenter. Chilling also promotes a reaction between proteins and tannins or polyphenols that results in chill haze. The great part of having chill haze at this stage of the game is that it will settle to the bottom of the fermenter. In a commercial brewery the settling time takes weeks, but luckily for homebrewers, beer depth in a carboy is about two feet and the settling time is measured in days, rather than weeks.

By siphoning off of the cold crashed beer into a secondary and storing this cold as well, the yeast can drop out even more to improve the clarity.

12. Skim and Whirlpool! As the wort boils you can use a spoon or strainer to filter off excess trub that rises to the top. Whirlpooling employs 2 methods of separating the trub from the wort. The first one is sedimentation, which means the trub will sink to the bottom when left alone. The second one is centrifugal force which forces the trub into the center of the pot. If both methods are used, the trub will be collected in a nice trub-cone in the center of the pot. This is the main trub separation technique that is used in commercial breweries before the wort is chilled. In a home brewing set-up, whirlpooling can be used before or after the wort is chilled. The latter also allows for the partial removal of cold break before the wort is transfered to the fermenter.

While sedimentation alone would work, the trub would thus be evenly spread on the bottom of the pot, preventing you from siphoning as low as you could if the trub was collected in a cone.

Whirlpooling is a method highly advised and used by Derrell. Here is a basic photo-tutorial. Basically, after you quickly cool the wort with an immersion chiller you stir the wort quickly to make a centrifugal “whirlpool”. Cover the pot and leave it alone for 20 minutes. This allows the trub to settle and most of it will settle towards the center. Rack off the top of the trub into the fermenter.

13. Choose a yeast high in flocculation: Flocculation is defined simply as the rate at which a particular yeast strain will fall out of the beer once fermentation is complete. If you choose a yeast strain with a high flocculation rating, it will clear much more quickly than one with a low flocculation rate. Flocculation should not be your only consideration, but if you have a choice, pick a yeast strain that both matches the style of your beer and has medium to high flocculation.

While this last tip may seem obvious to more experienced brewers, it is a very common mistake that can cause a beer to be cloudy. I hope all these tips help you guys out. Good luck! Happy brewing!

Advertisements
This entry was posted in Homebrewing. Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s