Cold Crashing Beer for Improved Beer Clarity

Cold Crashing Beer For Greater Clarity

The term cold crashing beer is a phrase that many new brewers hear over and over again.  Truth be told, it is the next step that many brewers take to improve the clarity of their brew.  Cold crashing beer is a simple step that will increase your beer clarity with very little work.  There is, of course, a catch.

For cold crashing beer, you need to be able to control the temperature of your beer.  To do this, many homebrewers rely on either the weather or a temperature controlled fermentation chamber.  I started off by using the winter temperatures in my garage to cold crash.  This only worked seasonally.  Since then, I have a dedicated fermentation chamber that is capable of cold crashing.

(Want to build a fermentation chamber?  See our article Fermentation Chamber Build – Future Keezer.)

What is Cold Crashing Beer?

Cold crashing beer is the act of lowering the fermentation chamber to cold but not freezing.  I place my beer 32F for forty-eight hours to accomplish my desired level of beer clarity.  During this time, science magic takes place to create a clear beer for bottling or kegging.

Ok, so science magic isn’t the best definition.  What actually takes place is called flocculation.  Flocculation is commonly referred to as flocc by many homebrewers.  This means that suspended yeasts and proteins in the beer group together and fall out of suspension.  High levels of beer clarity can be achieved by cold crashing beer but you’ll find greater results if you pair it with other clarity techniques.

(Learn about other easy steps new homebrewers can take to improve their beer clarity by reading Six Ways to Increase Homebrew Clarity.)

How Can You Cold Crash?

The easiest way to give cold crashing a try is by waiting until winter.  This only works for people who live in a location that has a cold winter.  I did my first cold crashes by placing my fermenter in the coldest spot in my garage.  I was able to achieve 35F and hold my brew there indefinitely.  The result was a much clearer beer and it drove me to create my first fermentation chamber.

There are different ways to build a fermentation chamber.  I have converted a chest freezer by using an InkBird temperature controller.  The set up took less than five minutes to program.  I can use the fermentation chamber to lager, to ferment at constant temperatures, and cold crash.  I highly suggest this because it was easy, and it creates a perfect environment for fermentation which will increase the quality of your beer.

There is another common way to build a fermentation chamber that doesn’t involve using a chest freezer.  Many brewers have built cases out of foam board that fit their fermenters.  Then by using small fans, frozen water bottles, and a thermostat, create a temperature controlled environment without the use of a freezer.  While I admire the creativity used in creating these, it’s a time-consuming build and requires frequent changing of the frozen water bottles.

(See the Son of Fermentation chamber build from the Homebrewer’s Association)

When Should You Cold Crash Beer?

Cold crashing should be the last step before packaging.  This means fermentation should be completed.  You need to measure your specific gravity to ensure this is true.  Homebrewers not brewing specific gravity can wait extra time to ensure this has occurred.  If a yeast strain typically ferments completely in ten days, then wait fourteen to ensure fermentation is complete.

(Not checking your gravity?  Using a refractometer is cheap and easy.  Find out how by reading How to Use a Refractometer for Beer.)

Bottling and Kegging After Cold Crashing Beer

If kegging your brew, proceed as usually.  Cold crashing beer will have zero impact on your carbonation.  If you’re bottling your brew, achieving high levels of clarity will impact your carbonation.  You will find that by flocculating out more yeast that your carbonation time will increase.  You can expect your one to two week carbonation to become two or three weeks.  If you’re unhappy with your level of carbonation, simply wait another week.  You do not need to add yeast to the bottles for bottle carbonation to work after cold crashing beer.

What About Dry Hopping My Beer?

This is a common question asked by many brewers.  Should you dry hop before or after cold crashing?  The goal of cold crashing is to settle out matter that would create a cloudy beer.  By adding dry hops after cold crashing beer, you decrease the overall clarity.  You will want to dry hop and then crash.

Other Ways to Clarify

Cold crashing beer is just one tool in the homebrewer’s bag of tricks.  It is best when used in combination with other clarifying techniques.  Clarifiers are easily added to the brew kettle such as Whirlfloc or Irish Moss.  Using a clarifier during brewing and cold crashing are the two techniques I use on every brew day when my beer style dictates clarity.  Many brewers also use fining agents and gelatin to improve their beer clarity.

(Learn about other easy steps new homebrewers can take to improve their beer clarity by reading Six Ways to Increase Homebrew Clarity.)

Cold crashing beer is a great step forward for many beginning brewers.  If you’re willing to build a chest freezer fermentation chamber, you will have a multi use tool capable of accomplishing many tasks.  Cold crashing beer is best used as one of multiple tools throughout the brewing process to improve the overall clarity of the final beer.

If you enjoyed the post, please be sure to like, comment, and share below.  I greatly appreciate the support!


Happy Brewing!

Ryan Caldbeck

Please follow and like us:

Leave a Reply

Your email address will not be published.