Clear Wort, Clear Beer - Tips from Yooper - Beer, Wine, Mead, & Cider Brewing Discussion Community.

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Many brewers find that one of the issues they face is the lack of wort and beer clarity. While haze and cloudiness do not necessarily impact the flavor of the beer, it does contribute to long term stability issues, as well being aesthetically displeasing.One simple way to help create a clearer beer is to create a clear wort. That sounds intuitive in a way, but it's easier said than done.
Several things contribute to haze, including yeast in suspension, but as a general rule of thumb "Clear wort makes clear beer" . If the wort is clear going into the fermenter, the things that may impact clarity later are easier to identify. Things like yeast haze and hops haze (from dryhopping) are easy to pick out in a finished beer. We will discuss chill haze, and how a clear wort can help or prevent it altogether.
First, wort of course comes from grain and the magic of the enzymatic activity of the mash takes the starch from the malted grain and turns it into fermentable sugar. A good mash pH helps with all of this. There are other things in the wort besides sugar, including proteins, tannins, polyphenols, and so on. Some grains (notably wheat) have more protein than others. It is during the boil that the rolling action of the boil causes foam to rise up- and threaten to boil over! The wort will continue to foam, until the protein starts to clump together and then get heavy enough to fall back into the wort. This is called the 'hot break". Once the hot break occurs, the wort will look a bit like egg drop soup, and have fine particles of protein throughout. After that happens, the wort will not threaten to boil over again, so you know that you've had your hot break.


A small sample of the wort after the hot break:

A good hot break will go a long way to the creation of clear wort. It's not just proteins that are creating the hot break reaction- in addition to the proteins, other polypeptides present in the wort will combine with tannins or polyphenols and become part of the hot break, due to their electrical charges. Other reactions are happening during the boil also- DMS precursors are driven off, isomerization of hops oils, color development due to maillard reactions, concentration of the wort, and the pH of the wort will drop, primarly due to the precipitation of calcium phosphate. Calcium in the brewing water reacts with phosphates from the malt, and this reaction will lower the wort pH.
The next item to discuss for wort clarity is then the 'cold break'. Cold break happens when the finished wort cools. Cold break is again mostly proteins, but another group of proteins that need to precipitate out of the wort to form a clear wort. The lack of a cold break is generally not a big issue in the flavor of the finished beer- instead it is mostly an aesthetic issue but it can affect long term stability of the beer. For most homebrewers, that isn't an issue either, as we rarely have to worry about that, unlike commercial breweries. Still, from an aesthetics standpoint many brewers would prefer to have clear beer to serve to friends and guests.
Quick chilling helps form a good cold break, and kettle finings such as whirlfloc or Irish moss can be helpful in that reaction.
Here is a hydrometer sample of wort straight from the kettle, with both the hot break and cold break suspended in the cooled wort:

That isn't very appealing! But within 5 minutes or so, gravity does its magic and the hot break and the cold break start to fall out:

Within 15 minutes, the hydrometer sample is perfectly clear, with the break material on the bottom:

By the time the wort is chilled completely, the wort is completely clear. When this beer is finished, if the beer is cloudy then it's most likely a yeast haze, or if the beer is dryhopped there could be a hops haze. Some yeast strains are non-flocculant and will not clear well without filtering, while other yeast strains (such as the English strains) will clear the beer well when fermentation is finished. Hops haze is generally an oil slick-type of haze, and does not create a murky beer. Some ingredients, like wheat, can create a haze due to the large amount of protein in it. There are some advantages to a beer with wheat as an ingredient, such as great foam and head retention.
If a beer is cloudy after fermentation, there are some techniques that can clear the beer even without filtering. Cold crashing, adding finings like gelatin, and time can all work to create a clear finished beer. If you start with a clear wort, finishing the beer so that it is clear is much easier, often without any post-fermentation action by the brewer. While a clear wort doesn't always guarantee a clear beer, it does tend to happen more easily. It's worth pursuing a good hot break, and a good break, as well as maintaining a proper mash pH to enhance the odds of making a clear beer with minimal effort.
Great article! You got me thinking if i'm hampering the formation of hot break by turning down the heat to control boil-overs. I have a 10gal kettle that I boil 7gal in for a 5 gal batch. I usually end up turning the burner way down or even off during the first boil when it threatens to boil over, then I turn it back up until it threatens again, and the process kind of repeats for 10 min or so until the foam dies dies and I can boil without worry...that is until the first hops are tossed in.
Well written article! I am left curious as to how exactly mash pH plays into clarity, but I could easily believe it does. I am interested in finding more information on how clarity effects stability, as well.
Good article, I really like the emphasis on pre-fermentation practices. Fining agents/cold crashing/cold aging can do wonders for clearing beer, but it sure makes it a lot harder if you don't get clear wort on the front end.
THe pictures of the hot/cold break in the sample are awesome, this is usually how I tell if I did a good job getting to a boil, and chilling, I love to see the solids settle....
I've heard that simethicone (fermcap-S) does wonders preventing boil-overs. I recently bought a 20gallon boil kettle so I hope I'd be ok wrt boil-overs even with a 10gallon batch but I'm going to add some anyhow. Cheers!
@JayDubWill- it sounds like you're doing it correctly. Once it no longer threatens to boil over, it's over the 'hot break'. Thereafter, a rolling boil is enough even if the burner is at lower temperature. As long as it's boiling, it's fine- it doesn't have to have a rocking hard boil.
@DSorenson- that sounds like another article topic. I will pursue that soon, as maybe others would be interested as well.
I have noticed that my hot break increased when I started using fermcap S, or the 5 Star equivalent, to control boil-overs. Any ideas how the addition of silicone effects the coagulation of proteins in the wort?
@JayDubWill try using a spray bottle of StarSan. I keep one on my brew cart, and give that foam a spritz right before the wort starts to boil. It'll break up the head so the liquid can roll properly without rolling out of the kettle.
Awesome article! I want to research more about mash ph and learn more. That will be my next step in my never ending homebrew journey. Thank you Yooper!!!
Are you saying the "cold break" happens before any hop additions, or is it just the time spent cooling the wort after the boil?
@Benedetto - The blue hose is Loc-Line modular hose ( I've seen a bunch of home brewers use it to direct the wort return in their mashes. I haven't used it before so can't speak to it's effectiveness, especially at higher temperatures.
I'm probably mis-reading this but it sounds like both the hot and cold break are things you almost couldn't avoid. The hot break just happens automatically after you've boiled it for a certain amount of time so unless you're doing an extremely short boil it's just going to happen no matter what. Does fermcap have an impact on this process?
The cold break happens as you chill your beer, which you have to do before you pitch your wort. Does it only happen if you chill it fast enough? If so, how fast do you have to chill it to get a good cold break?
@JayDubWill a wooden spoon over the lip of the kettle will stop a boil over. same as it does when cooking pasta, although i cannot say as to how sanitary this is.
@jma99- I have not noticed the difference in the amount of cold or hot break when using Fercap-S. It's worth considering.
@Benedetto- that is 'loc-line', my return tubing in my boil kettle from when I pump from the MLT or recirculate during hop stands. It's flexible, and temperature is rated to 500 degrees. I've had it for about 8 years!
@mrgrimm101- "hot break" happens before adding hops, except for FWH (first wort hops). After the hot break, the timer can be set for 60 minutes and the first hop addition added. The cold break happens after/during the chill, when the wort is cooled after the boil.
I know this will be an extremely noob question...but after cooling my wort with a wort chiller, I've just been dumping the entire contents of the kettle into my fermenting bucket. (Note that I'm doing steeping grains with extract, not all grain) Since you are showing solids settling out of the wort during the 'cold break', should I be racking the wort into the fermenter to leave the break material behind?
@cernst151- Hot break doesn't happen 'automatically', as it takes a good hard rolling boil for it to happen. Some brewers are afraid of a boil over, or don't have a strong enough burner and never get to that point. It's the action of the rolling of the boil along with heat that makes the hot break happen.
Cold break can happen even for no-chill brewers, but it seems that it happens more readily and more thoroughly by chilling the wort quickly to under 80 degrees.
@antvq- Some brewers do strain their wort into the fermenter. I do not.
That hydrometer sample is right out of my return line into my fermenter. The break material is heavy enough that it settles out into the bottom of the fermenter without any issues at all. I've read in several sources that cold break material can improve yeast health, but I have not researched that and don't know the mechanism of that.
Interesting to see your gadget in the process, the loc-line. Where do you get it and can I see the way in which it is hooked up with the pump? Lots of us are using silicon tubing I assume for all grain. Might be nice to see the alternatives. Thanks! Nice article.
That locline looks.almost exactly like directional air compressor nozzles to blow air away from the line you are trying to cut. Found at places like Rocklers.
Good stuff! This is another testament to the fact that homebrewing never ceases to be a wealth of knowledge and satisfaction. If your passionate about producing good beer your education never ceases. God I love everything about it!!