Crystal clear beer is an attainable goal for every brewer. But it may not be possible and is inappropriate for certain styles. Whether you use recipe design, brewing processes, or fining agents, you can have bright beer in your glass.
What Causes Haze
In order to brew clear beer it’s important to first understand what causes haze.
Polyphenols and Proteins
Polyphenols come up a lot in the brewing world, for good reason. Polyphenols in beer are comprised of flavonoids and tannoids. Through a series of reactions they bond with proteins in beer and produce haze forming compounds. I’m really oversimplifying this but… polyphenols + protein = haze.
To dig more into the technical nitty gritty of how polyphenols and proteins form haze, check out this article from kegerator.com.
Both malt and hops contribute to the overall amount of polyphenols. However, hops have a high polyphenol content compared to malt. The bottom line is: more hops equals more haze.
Certain malts and adjuncts are higher in protein. Oats and rye, for example, are high and corn and rice are low.
Compare the recipes of an American light lager (crystal clear) with that of a New England IPA (hazy). You can see how both hopping rates, grain selection, and processes affect the clarity of the final product.
Yeast and Bacteria
Certain yeast stains, especially wild ones, can be low flocculating and thus contribute to haze. There are certain strains of lactobacillus that can cause haze as a by-product of their consumption of sugars. This is yet another reason to have steller sanitation practices as a brewer.
Kettle soured beers can be hazy from the lack of protein precipitation during the boil. This is due to a low pH. However, this is counteracted by a reduction of haze forming polyphenols. So, not all kettle sours are hazy.
Several factors will hasten reactions between polyphenols and proteins. Time, heat, oxygen, light, copper, and iron all speed up the rate at which haze is formed.
Brewing Processes for Clearer Beer
Much can be done in the process of brewing to result in a clearer beer.
Starting with the recipe, use a grist that is lower in protein. Also for the sake of an example, avoid Hazy IPA levels of hops in your IPL recipe. You can up the amount of rice or corn adjuncts and use oats or rye sparingly. Use a high flocculating yeast strain.
Hot and Cold Break
During the boil, clumps of protein will form. This is the “hot break”. These clumps are part of the trub that you’ll find at the bottom of the kettle when you’re done boiling and everything precipitated. In the interest of clear beer, it is important to boil long enough for a complete hot break. Usually this takes 5-20 minutes. Most brewers boil for 60 minutes…that’s plenty of time.
When you chill your wort rapidly, a second reaction occurs known as the “cold break”. This is when more haze-causing proteins settle out of the wort. For this to happen, you must chill your beer from boiling to room temp as quickly as possible.
Before packaging, many brewers “cold crash” their beer. This can be difficult to accomplish without introducing a lot of oxygen. The action of cooling your beer will pull air into your fermentor and eventually stale your fresh beer. I’m not a proponent of cold crashing without the proper equipment setup.
Time will help a lot of haze inducing particles settle out of your beer. In many cases, the only thing you need for clear beer is patience. Cold temps and leaving your beer in the bottle or keg for long enough will go a long way towards bright beer.
When you serve your beer, pour your bottles with care and avoid rousing the yeast and sediment at the bottom of the bottle. Certainly, you don’t want to pour all that sediment into your glass…unless you’re drinking a Hefeweizen. If you keg, the first several pints you pour will likely be hazy. Depending on how murky they are you may choose to drink them or… serve them to your mother-in-law.
Methods of Clarification
There are a lot of ways to clear up your beer. We’ll cover the most commonly used methods here.
Gelatin is a great option for clearing up your beer. You can find gelatin at any grocery store. It’s made from animal hooves so it’s definitely not vegan and probably not kosher.
To use it, you can add it to your fermentor (after cold crashing) or to your keg. It’s important for your beer to be cooled down to fridge temps for gelatin to work its protein and particle precipitating magic.
1 tsp of gelatin dissolved into ¾ cup of water at 155 F is all you need for a 5 gallon batch.
The biggest drawback to clearing your beer this way is exposure to oxygen. That’s why I prefer the following method.
Irish moss is a type of seaweed. It’s a traditional kettle fining agent and causes the formation of larger clumps of proteins in the kettle. These clumps settle to the bottom of the kettle so you can avoid transferring them to your fermentor after chilling the wort.
Irish moss comes in many forms and can be added to the kettle for the last 15 minutes of the boil.
Isinglass, is gelatin from fish swim bladders. Use it like you would gelatin, post fermentation and at cold temps. It is most effective when used in conjunction with silicic acid.
BSG produces a product known as Biofine® Clear that is silicic acid in water. It’s a purified product so there’s no concern about infecting your beer. It only acts on water loving proteins so it will leave behind proteins that aid in head retention. It’s more or less a vegan friendly version of gelatin.
You can dose your beer post fermentation with ¼ – 2 tablespoons of Biofine® Clear. That amount is for 5 gallons of beer. It’s more effective at colder temperature and will require specific dosing for each different beer. Start with a little and add more as needed.
There are other options out there but I don’t really recommend them for use on the homebrewing level. Polyvinylpolypyrrolidone (PVPP) is a plastic powder that will help precipitate polyphenols and proteins but it’s expensive and requires very exact dosing. Tannic acid and enzymes like papain act only on proteins and can also negatively affect the flavor of your beer.
Used correctly the three agents above are helpful but there are better options out there.
Time is probably everyone’s least favorite way of clearing a beer because it requires patience. But if you aren’t in a hurry then simply using good brewing techniques and allowing for enough time after packaging will give you good results.
This is a method usually regarded as something done by the pros. But there are of course homebrewers out there filtering their beer. If you don’t mind the hassle of cleaning and sanitizing and really want to achieve crystal clear beer in a timely manner, filtering is a great option.
Kirk Fleming wrote an in-depth article for BYO on the topic of filtering. If you’re interested in going the route of filtering, check it out here.
Now you know everything you need to in order to brew super bright and beautifully clear beer! I’ll leave you with the following personal story.
Last summer I brewed a batch of Saison. I used unmalted wheat, wild captured yeast, and the no-chill method. I didn’t use any kettle finings and I transferred a lot of trub into the fermentor. Oh, and I have the habit of squeezing the bag when I brew with my BIAB setup…bad dog. Squeezing the bag is generally regarded as a sure way of increasing the amount of hazy inducing particles and tannins.
After a few months in the bottle, I recently drank some of that Saison and…it was crystal clear! What’s my point? Time, temperature and gravity may prevail and clear up a multitude of brewing “sins”.
Finally, in your quest for clear beer, try combining a few of the methods we discussed. May your beer be cold and bright!